part-iv - indian railways no. part-iv description file no. date 1. speed restriction on emu/dmu/memu...
TRANSCRIPT
PART-IV
S No.
Part-IV
Description File No. Date
1. Speed restriction on EMU/DMU/MEMU in deflated condition.
SV.EMU.RAS
04.04.2008
2. Modification in Maintenance Manual due to Introduction of air spring at the secondary stage in ICF bogie coaches.
MC/CBE/MM
09.09.2009
3. Modification in Maintenance Manual and Brake Power certificate format due to introduction of air springs at secondary stage in ICF bogie coaches.
MC/CB/MM
18.09.2009
4. Introduction of air spring at the secondary suspension stage on ICF main line coaches- instruction for maintenance, spares and safety.
SV.AS.ML
10.11.2009
5. Problem of Feed Pipe Pressure in Duranto Express fitted with Air Suspension and Controlled Discharge Toilet System (CDTS)
SV.AS.ML
23.09.2010
6. Withdrawal of air spring of capacity 150 KN as per RDSO’s STR C-K106 (Rev.2) from service.
SV.EMU.RAS
05.01.2011
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 1 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-1
(For official use only)
INDIAN RAILWAYS
“MAINTENANCE INSTRUCTIONS ON
AIR SUSPENSION FOR
MAINLINE/RAJDHANI COACHES WITH ICF TYPE BOGIES
RDSO/2009/CG/CMI-01 September 2009
RESEARCH DESIGNS AND STANDARDS ORGANISATION MANAK NAGAR, LUCKNOW – 226011.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 2 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-2
SYNOPSIS Requirement of greater passenger comfort with reduced maintenance and have generated need for the Indian Railways to adopt air suspension for its coaching stock.
For Indian Railways, air suspension is a new technology and hence there is a need to impart awareness amongst officials engaged in handling of this system, regarding its working principle, functions and details of hardware and maintenance practices to be followed for various items. This booklet has been prepared with above objectives in view. Any suggestion directed towards improvement in the quality of the booklet shall be welcome which may be sent to Executive Director Standards/Carriage or Director/VDG/Carriage, Research Designs & Standards Organization, Manak Nagar, Lucknow-226011.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 3 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-3
INDEX
Item DESCRIPTION Page No.
1. INTRODUCTION 4
2. WORKING PRINCIPLE OF PNEUMATIC SUSPENSION 4
3. COMPARISON WITH EXISTING COIL SUSPENSION 4 4. ADVANTAGES OF AIR SUSPENSION 5
5. CHARACTERISTICS FEATURES OF AIR SUSPENSION 5
6. CONSTRUCTION DETAILS/CHARACTERISTICS OF AIR SPRING 5
7. SCHEMATIC LAYOUT OF PNEUMATIC SUSPENSION CONTROL 5 EQUIPMENTS
8. MODIFICATIONS FOR AIR SPRING FITMENT 5
9. OPERATING INSTRUCTIONS 6
10. DISMANTLING OF AIR SPRING FROM LOWER SPRING BEAM 6 (CRADLE) AND BOGIE BOLSTER.
11. INSPECTION & MAINTENANCE OF AIR SPRING 6
12. INSPECTION & MAINTENANCE OF LOWER SPRING BEAM 7
13. INSPECTION OF PIPE LINE 7
14. MOUNTING AIR SPRING ON LOWER SPRING BEAM AND BOLSTER 7
15. TEST FOR LEAKAGE 7
16. PROCEDURE FOR CHECKING OF BOGIE CLEARANCES ON EMU’S & 8
DMU’SPROVIDED WITH AIR SPRING
17. PROCEDURE FOR CENTRE BUFFER COUPLER HEIGHT ADJUSTMENT 8 IN WORKSHOP
18. INSTALLATION LEVER ADJUSTMENT 9
19. CHARACTERISTICS OF AIR SPRING/PERIODICAL INSPECTION OF 9 AIR SPRING SYSTEM ON MAINLINE COACHES
20. AIR SPRING SERVICE 10
21. AIR SPRING CONTROL EQUIPMENTS SERVICE 10
22. FIGURES 1 to 9 11-19
23. ANNEXURES A to J
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 4 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-4
MAINTENANCE INSTRUCTIONS
ON AIR SUSPENSION
1. INTRODUCTION:
Railway Board had approved fitment of air spring on AC Mainline ICF coaches for the purpose of oscillation trials. After simulation study at RDSO, design for mainline stock with air spring at secondary suspension has been evolved. Simulation studies have revealed a significant improvement in the quality of ride on ICF stock fitted with air springs over those fitted with conventional coiled springs. This is particularly significant with regard to the requirement of better riding on high speed Rajdhani and Shatabdi trains specially in Ist AC coaches. Oscillation trials have been conducted on ICF mainline bogie coaches successfully, with good results. Accordingly it has been decided by Railway Board to provide air springs (pneumatic suspension) on all stainless steel shell coaches (LHB type shell) provide with ICF bogies. The Pneumatic suspension has been proven, on DC-EMU, AC-EMU, AC-DC EMU and HHP-DMU.
2. WORKING PRINCIPLE OF PNEUMATIC SUSPENSION: Air suspension is a suspension where properties of air are used for cushioning effect (springiness). Enclosed pressurised air in a pre-defined chamber called air spring, made up of rubber bellow & emergency rubber spring, provides various suspension characteristics including damping. Air springs are height-controlled load levelling suspension devices. With changing loads, air spring reacts initially by changing the distance between air spring support and vehicle body. The height monitoring valve (called levelling valve) is in turn actuated, either taking the compressed air pressure to the air spring or releasing air pressure from it to the atmosphere. This process continues until the original height is restored. (See Fig.1 page No. 11). This mechanism ensures a constant floor height on coaches provided with air springs, irrespective of the load. This greatly reduce problems associated with low buffer / coupler heights.
3. COMPARISON WITH EXISTING COIL SUSPENSION:
Unlike steel spring, air springs retain their height under changing loads. The low natural frequency of air spring suspension remains virtually constant. In case of coil spring, deflection is proportionate to the load, therefore, under high payload situation, space constraint become critical, leading to the use of stiffer springs resulting in unsatisfactory ride behavior and reduced speed potential. Air springs through their control mechanism, offer a load proportionate stiffness, constant floor height and prospects of better ride behavior with higher speed potential. (See Fig.2 page No. 12).
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 5 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-5
4. ADVANTAGES OF AIR SUSPENSION: • Capable to sustain Super Dense Crush Loads typical of suburban traffic. • Maintain constant floor height of coach. • Provide superior ride comfort. • Virtually Constant natural frequency from tare to full loads, reducing passenger fatigue. • Isolation of structure borne noise, this improving comfort. • Improved reliability, reduced maintenance effort. • Flexibility to chose characteristics as per requirement at design stage.
5. CHARACTERISTICS FEATURES OF AIR SUSPENSION:
• Soft flexible characteristics in vertical direction
- Achieved by compression of air (See Fig.3 page No. 13). • Excellent lateral spring characteristics, as desired.
- Achieved by variation in effective area in lateral direction (See Fig.3 page No. 13).
• Avoids excess air consumption due to instantaneous modes of vehicle oscillation or change in air pressure. - Achieved by designing delayed reaction levelling valve (See Fig.4 page No. 14).
6. CONSTRUCTION DETAILS:
• Construction details of air spring are shown in (See Fig.5 page No. 15). (air spring with outside emergency spring), & Fig. 6 at page no.16 (air spring with inside emergency spring).
7. SCHEMATIC LAYOUT OF PNEUMATIC SUSPENSION CONTROL EQUIPMENTS:
A schematic layout of pneumatic suspension control equipments has been provided in Fig.7 at page no. 17.
8. MODIFICATION FOR FITMENT OF AIR SPRING IF REQUIRED: 8.1 Bogie Frame & Suspension:
• Air spring has been installed at secondary stage replacing steel coil springs. • A fixed lower spring beam (as cradle) to accommodate the air spring has been provided
on bogie bolster. • A lateral hydraulic damper and lateral bump stop have been provided at secondary stage. • Primary springs have been retained as steel spring. • Details are shown in Fig.8 at page no. 18 • Leveling valve provided between bogie frame and bogie bolster.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 6 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-6
8.2 Bogie bolster:
• Provision made for air inlet to air spring. • 40 lit addl. Reservoir connected to each air spring is provided. • Duplex check valve is provided.
8.3 Under frame: • A pipeline is drawn from M.R pipe (feed pipe) for pneumatic suspension • One isolating cock, one non return valve, one 150 lit air reservoir (auxiliary reservoir) one
air filter and two separate isolating cocks to isolate each bogie have been provided • A schematic diagram is shown in fig.7 at page no 17.
8.4 BASE PLATE:
• Base plate to be used should be as per drawing No. RDSO sketch- K4018 alt ‘1’ is enclosed as fig.9 at page no 19.
9. OPERATING INSTRUCTIONS:
• Train Driver to maintain 7 bar pressure in compressor. • In case of heavy leakage of air from air spring system, Isolate the affected bogie and
observe speed restriction at 60 km/h up to the terminal point for maintenance. 10. DISMANTLING OF AIR SPRING FROM LOWER SPRING BEAM (CRADLE)
AND BOGIE BOLSTER:
• Remove All Body, Bogie connections • Remove duplex check valve from bolster • Remove lateral & vertical shock absorber • Remove equalizing rod connection from both ends of lower spring beam if provided. • Remove connection between arm of levelling valve & installation lever. • Remove all 4 No. Bolts and nut with the help of M16 Allen key and suitable spanner from
bottom plate of air spring & lower spring beam. • Lift bolster up to bogie frame to clear the spigot of air spring. • Slide air spring from lower spring seat.
11. INSPECTION & MAINTENANCE OF AIR SPRING: • Inspect for any water collection in rubber bellow of air spring • Inspect the air spring for any damage or leakage. • Inspect air spring seat and top plates for corrosion, if corrosion noticed is paint with
primer & black paint.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 7 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-7
12. INSPECTION & MAINTENANCE OF LOWER SPRING BEAM:
• Inspect all welding joints of the lower spring beam (cradle) and repair if required. • Inspect air spring fixing holes of lower spring beam for elongation, if elongated build
them to dia.17 mm or dia. 26 mm. • Inspect the corrosion on top surface of lower spring beam, Remove the corrosion paint
with primer and black paint.
13. INSPECTION OF PIPE LINE:
• The air spring piping may be checked for any leakage/damage by soap test and repair if required.
14. MOUNTING AIR SPRING ON LOWER SPRING BEAM AND BOLSTER:
• "O" rings provided on air spring spigot must be changed. • Mount air spring on lower spring beam and match the holes of bottom plate of air spring
and holes of lower spring beam. • Tight all 4 nut-bolts with the help of M16 Allen key and suitable spanner. • Place the bolster on air spring ensuring no damage to spigot of air spring. • Connect levelling valve arm with installation lever. • Mount vertical and lateral shock absorber. • Connect all flexible/fixed pipe connections of bogie • All the threaded joints of air spring be sealed with thread sealing tape to avoid air leakage. • The filter of levelling valve must be cleaned.
15. TEST FOR LEAKAGE:
• Connect the hosepipes on the under frame piping with the levelling valves of the bogies. • Connect pressure gauges to the drain plug locations of 150-litre reservoir. • Provide packing in the gap between bolster & bogie frame. • Connect the 150-litre reservoir on the under frame to the compressed air source of
pressure 9.0 kgf/cm2. • Allow air into the air springs to a value of 9.0 kgf/cm2 in the pressure gauge by adjusting
the horizontal lever of the levelling valve and keep it in the same position. • Close the isolating cock connecting MR pipe with 150-litre reservoir. • Test all pipe joints for leakages. • Check the pressure gauge readings after one hour. The pressure drop should be within 1%
of the test pressure 9.0 kgf/cm2. • Release the air completely by dropping the horizontal lever. • Remove the packing.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 8 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-8
16. PROCEDURE FOR CHECKING BOGIE CLEARANCES ON AC AND NON AC COACHES PROVIDED WITH AIR SPRINGS :
• Firstly find out the type of bogie as AC EOG (16 T), AC SG (16T), or NON AC (13 T) coaches and make RCF or ICF. List of relevant drawings are as under: TYPE OF COACH ICF DRAWING No. RCF DRAWING No. AC EOG(16 T) WTAC5-0-0-501
(ANNEXURE.-C) -
AC SG(16 T) LWGSCWAC-0-0-001 (ANNEXURE.-D)
CA00001(ANNEXURE.-F)
NON AC (13 T) LGS-0-0-001 (ANNEXURE.-E)
CA00002(ANNEXURE.-G)
• Than the coach should be placed at leveled track. • The primary springs should be grouped as per ICF drawing no. ICF/STD-9-0-003 placed at
Annexure-H, in which the different type of primary springs is grouped for air spring bogie and other type of bogie.
• The primary springs are used for the air spring bogies as follows: TYPE OF COACH ICF DRAWING No. RCF DRAWING No. AC EOG(16 T) WTAC-0-1-202 WTAC-0-1-202 AC SG(16 T) WTAC-0-1-202 AW01101 NON AC (13 T) WTAC-0-1-202 CC01129 POWER CAR WLRRM8-0-1-801 -
• Place the proper primary springs and compensating rings in AC EOG,AC SG and NON AC coaches with air spring bogie as per following suspension diagram: TYPE OF COACH
ICF DRAWING No. RCF DRAWING No.
AC EOG(16 T) WTAC5-9-0-501(ANNEXURE.-I) - AC SG(16 T) - CA90001(ANNEXURE.-J) NON AC (13 T) - CA90001
• Than maintain the bogie corner heights as per relevant suspension diagram. • After the bogie corner height is maintained, adjust the air spring height as per relevant suspension
diagram with the help of installation lever.
17. PROCEDURE FOR CENTRE BUFFER COUPLER HEIGHT ADJUSTMENT IN WORKSHOP: • After POH and before assembling the bogie, measure the wheel diameter. • Depending upon the wheel diameter, place wooden packing of required thickness under the
flange of lower spring seat as indicated in the following table: Average wheel dia. between the two wheels on the same bogie
Thickness of hard packing ring (mm)
889 mm to 864 mm 13 863 mm to 840 mm 26 840 mm to 820 mm 38 819 mm 48
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 9 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-9
18. INSTALLATION LEVER ADJUSTMENT:
Adjustment of installation levers is essential for proper levelling of coach body. The adjustment needs to be carried out in AOH/POH or intermediate dismantling of levelling valve system. The procedure to be followed is as under: • Keep the coach on a level track. • Connect pressure gauges to the drain plug locations of all 40-litre reservoirs in the bogie. • Place the car body on the two bogies and hook it up to the air supply (by opening the
isolating cock 1a). • First open only the isolating cock (1c0, thereby releasing the air supply for bogie “1”and
affix the level control rod assembly to the valves). • On the rod assemblies (6) set the general level (-5mm) that the car body is ultimately to
have above the bogie frame and the upper edge of the bogie. • Insert the suitable block (ca 10 mm under the nominal height and preferably of hardwood)
centrally between the bogie frame and the car body and lower the car body onto the block by removing the valve rod assembly (6).
• Shut the isolating cock (1c) again, thereby interrupting the supply of air to bogie“1” and open isolating cock (1b), and thereby releasing the air supply to bogie “2”.
• Affix level control rod assemblies (6) to the valves (5) and set the assemblies (6) to desired level.
• Insert a suitable block (preferably hardwood) centrally between the bogie frame and the car body and lower the car body onto block by removing the valve and assemblies (6).
• Shut isolating cock (1b) again, thereby cutting off the air supply to bogie “2” and open isolating cock (1c), and thereby releasing the air supply to bogie “1”.
• Attach level control rod assemblies (6) to the valves (5) and, after aeration, carefully adjust settings on both rod assemblies (6) simultaneously (proceeding from below) until the desired car body height has been attained.
• Remove the block from bogie “1”. • Reopen isolating cock (1b), thereby releasing air to bogie “2”, and while at the same time
hanging the rod assembly (6) back in place in bogie “2”. • Remove the block from bogie “2”. • Recheck the height at all measuring points. CAUTION: If the difference in pressure of the air in the air springs of the same bogie is more than setting pressure of the duplex check valve i.e. 1.5 bar, then the air will continuously escape from one air spring to the other through the duplex check valve and then to atmosphere. • Tighten the installation lever lock nuts with the horizontal lever, so that the setting will
not be disturbed. • Repeat the above procedure for the second bogie. • Disconnect the pressure gauges and replace the drain plugs.
19. CHARACTERISTICS OF AIR SPRING / PERIODICAL INSPECTION OF AIR SPRING
SYSTEM ON MAINLINE COACHES:
These are provided at Annexure – A and B for reference and implementation.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 10 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-10
20. AIR SPRING SERVICE: For the maintenance of the air springs, the respective vendors maintenance manuals should be followed. These maintenance manuals shall be provided by the respective vendors at the time of delivery of air springs.
21. AIR SPRING CONTROL EQUIPMENT SERVICE:
For the maintenance of the air springs control equipment, the respective vendor’s maintenance manuals should be followed. These maintenance manuals shall be provided by the respective vendors at the time of delivery of air spring control equipments.
-------------------------------------
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 11 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-11
WORKING PRINCIPLE OF PNEUMATIC SUSPENSION
FIG. NO. 1
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 12 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-12
FIG
. No.
2
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 13 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-13
FIG
. No.
3 V
ER
TIC
AL
AN
D L
ATE
RA
L A
CTI
ON
OF
AIR
SP
RIN
G
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 14 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-14
DEL
AY
ED R
EAC
TIO
N O
F C
ON
TRO
L V
ALV
E TO
AV
OID
EX
CES
SIV
E A
IR C
ON
SULA
TIO
N
FIG
. N
o.
4
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 15 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-15
FIG.
NO
. 5: A
IR S
PRIN
G W
ITH
OU
TSID
E EM
ERG
ENC
Y SP
RIN
G
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 16 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-16
FIG.
NO
. 6 :
AIR
SPR
ING
WIT
H IN
SID
E EM
ERG
ENC
Y SP
RIN
G
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 17 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-17
FIG.
NO
. 7: S
CH
EMAT
IC D
IAG
RA
M O
F A
IR S
USP
ENSI
ON
EQ
UIP
MEN
TS
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 18 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-18
CR
ADLE
FIG.
No.
8 :
BO
GIE
GEN
ERA
L A
RR
AN
GEM
ENT
WIT
H A
IR S
PRIN
G R
ETR
OFI
TMEN
T
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 19 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-19
FIG No. 9 : BASE PLATE FOR AIR SPRING
Ref: CGW 0001,Rev.-3
Date / Month of issue: September, 2009
Page 20 of 21
Maintenance Instruction No.
CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-20
ANNEXURE-A
GENERAL TECHNICAL DATA AS PER RDSO STR C-K509
1. STATIC VERTICAL LOADS ON AIR SPRING
Tare load -------------------------- -- 50.0 KN Full load --------------------------- -- 140.0 KN
2. VERTICAL STIFFNESS
At dz + 20 mm and constant speed of 5mm/sec, the vertical stiffness (Cz) shall be:
Vertical stiffness Cz IN N/mm Load in KN (Static) Additional Volume 20dm3 Additional volume 40dm3
50 550±50 N/mm 400±50N/mm 115 875±75N/mm 625±75N/mm 140 1000±100N/mm 700±100N/mm
3. HORIZONTAL STIFFNESS
At dy +20 mm at constant speed of 5 mm/sec, the lateral stiffness (Cy) shall be:
Load in KN (Static) Lateral stiffness Cy IN N/mm 50 150 ±25 N/mm 115 175±25 N/mm 140 200±25 N/mm
4. Min. height of air spring under full load with no air and without spigot - 210 mm
5. Installed height without spigot - 255+0-5 mm.
Ref: CGW 0001,Rev.-3
Date / Month of issue: September, 2009
Page 21 of 21
Maintenance Instruction No.
CMI- RDSO/2009/CG/CMI-01
PERIODICAL INSPECTION OF AIR SPRINGS SYSTEM ON MAINLINE COACHES EXISTING
SCHEDULE OF INSPECTION
INSPECTION ON AIR SPRING SYSTEM
INSPECTION
SITE Primary / Secondary
• Visual check: General conditions which includes any external damages, air leakage, infringement of any fittings, etc.
• Draining of 150-liter air reservoir of air spring • Check the position of isolating cock and drain cock, these should be on and off position respectively.
Pit line
Schedule-A • As in Primary / Secondary schedule and Draining of 40-liter reservoir. • Cleaning of leveling valve filter as per manufacturer’s manual. The procedure is shown at Annexure B/1.
Pit line
Schedule -B • As in Schedule -A • Checking of installation lever with inflated air spring for normal function, tightening of installation lever
nuts and protection screen nuts, tightening of bracket of all flexible hoses. • Cleaning of air filter of 150-liter reservoir.
Pit line
Schedule -C • As in Schedule -B & • Thorough checking of air spring, bulging of bellow, air leakage. • Air suspension pipe leakage check by using soap water. • Removing dust mud & oil deposit if any, on air spring and control equipment. • Thorough checking of lower spring beam for any crack and deformation. • Tightening of air spring bottom plate bolts and nuts. • Measurement of bogie clearances related to air spring.
Sick line
AOH/POH • As in Schedule - C and • Through visual check of air spring as per Annexure-C or D after dismantling as in clause 10. • Remove all valves and carry out external cleaning, overhauling and function test should be done as given
in maintenance manual supplied by respective vendors. • Checking securing arrangement of steel pipeline. • Leakage test of air springs as per clause 15. • Installation lever adjustment as per clause 18. • Lateral damper condition should be checked and replace with fresh if damaged. • Air spring bellow should not be painted.
Depot/ Work shop
AN
NEX
UR
E-B
RDSO/Lucknow Page-21
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 1 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-1
(For official use only)
INDIAN RAILWAYS
“MAINTENANCE INSTRUCTIONS ON
AIR SUSPENSION FOR
MAINLINE/RAJDHANI COACHES WITH ICF TYPE BOGIES
RDSO/2009/CG/CMI-01 September 2009
RESEARCH DESIGNS AND STANDARDS ORGANISATION MANAK NAGAR, LUCKNOW – 226011.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 2 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-2
SYNOPSIS Requirement of greater passenger comfort with reduced maintenance and have generated need for the Indian Railways to adopt air suspension for its coaching stock.
For Indian Railways, air suspension is a new technology and hence there is a need to impart awareness amongst officials engaged in handling of this system, regarding its working principle, functions and details of hardware and maintenance practices to be followed for various items. This booklet has been prepared with above objectives in view. Any suggestion directed towards improvement in the quality of the booklet shall be welcome which may be sent to Executive Director Standards/Carriage or Director/VDG/Carriage, Research Designs & Standards Organization, Manak Nagar, Lucknow-226011.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 3 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-3
INDEX
Item DESCRIPTION Page No.
1. INTRODUCTION 4
2. WORKING PRINCIPLE OF PNEUMATIC SUSPENSION 4
3. COMPARISON WITH EXISTING COIL SUSPENSION 4 4. ADVANTAGES OF AIR SUSPENSION 5
5. CHARACTERISTICS FEATURES OF AIR SUSPENSION 5
6. CONSTRUCTION DETAILS/CHARACTERISTICS OF AIR SPRING 5
7. SCHEMATIC LAYOUT OF PNEUMATIC SUSPENSION CONTROL 5 EQUIPMENTS
8. MODIFICATIONS FOR AIR SPRING FITMENT 5
9. OPERATING INSTRUCTIONS 6
10. DISMANTLING OF AIR SPRING FROM LOWER SPRING BEAM 6 (CRADLE) AND BOGIE BOLSTER.
11. INSPECTION & MAINTENANCE OF AIR SPRING 6
12. INSPECTION & MAINTENANCE OF LOWER SPRING BEAM 7
13. INSPECTION OF PIPE LINE 7
14. MOUNTING AIR SPRING ON LOWER SPRING BEAM AND BOLSTER 7
15. TEST FOR LEAKAGE 7
16. PROCEDURE FOR CHECKING OF BOGIE CLEARANCES ON EMU’S & 8
DMU’SPROVIDED WITH AIR SPRING
17. PROCEDURE FOR CENTRE BUFFER COUPLER HEIGHT ADJUSTMENT 8 IN WORKSHOP
18. INSTALLATION LEVER ADJUSTMENT 9
19. CHARACTERISTICS OF AIR SPRING/PERIODICAL INSPECTION OF 9 AIR SPRING SYSTEM ON MAINLINE COACHES
20. AIR SPRING SERVICE 10
21. AIR SPRING CONTROL EQUIPMENTS SERVICE 10
22. FIGURES 1 to 9 11-19
23. ANNEXURES A to J
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 4 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-4
MAINTENANCE INSTRUCTIONS
ON AIR SUSPENSION
1. INTRODUCTION:
Railway Board had approved fitment of air spring on AC Mainline ICF coaches for the purpose of oscillation trials. After simulation study at RDSO, design for mainline stock with air spring at secondary suspension has been evolved. Simulation studies have revealed a significant improvement in the quality of ride on ICF stock fitted with air springs over those fitted with conventional coiled springs. This is particularly significant with regard to the requirement of better riding on high speed Rajdhani and Shatabdi trains specially in Ist AC coaches. Oscillation trials have been conducted on ICF mainline bogie coaches successfully, with good results. Accordingly it has been decided by Railway Board to provide air springs (pneumatic suspension) on all stainless steel shell coaches (LHB type shell) provide with ICF bogies. The Pneumatic suspension has been proven, on DC-EMU, AC-EMU, AC-DC EMU and HHP-DMU.
2. WORKING PRINCIPLE OF PNEUMATIC SUSPENSION: Air suspension is a suspension where properties of air are used for cushioning effect (springiness). Enclosed pressurised air in a pre-defined chamber called air spring, made up of rubber bellow & emergency rubber spring, provides various suspension characteristics including damping. Air springs are height-controlled load levelling suspension devices. With changing loads, air spring reacts initially by changing the distance between air spring support and vehicle body. The height monitoring valve (called levelling valve) is in turn actuated, either taking the compressed air pressure to the air spring or releasing air pressure from it to the atmosphere. This process continues until the original height is restored. (See Fig.1 page No. 11). This mechanism ensures a constant floor height on coaches provided with air springs, irrespective of the load. This greatly reduce problems associated with low buffer / coupler heights.
3. COMPARISON WITH EXISTING COIL SUSPENSION:
Unlike steel spring, air springs retain their height under changing loads. The low natural frequency of air spring suspension remains virtually constant. In case of coil spring, deflection is proportionate to the load, therefore, under high payload situation, space constraint become critical, leading to the use of stiffer springs resulting in unsatisfactory ride behavior and reduced speed potential. Air springs through their control mechanism, offer a load proportionate stiffness, constant floor height and prospects of better ride behavior with higher speed potential. (See Fig.2 page No. 12).
Ref: CGW 0001,Rev.-3 Date / Month of issue:
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4. ADVANTAGES OF AIR SUSPENSION: • Capable to sustain Super Dense Crush Loads typical of suburban traffic. • Maintain constant floor height of coach. • Provide superior ride comfort. • Virtually Constant natural frequency from tare to full loads, reducing passenger fatigue. • Isolation of structure borne noise, this improving comfort. • Improved reliability, reduced maintenance effort. • Flexibility to chose characteristics as per requirement at design stage.
5. CHARACTERISTICS FEATURES OF AIR SUSPENSION:
• Soft flexible characteristics in vertical direction
- Achieved by compression of air (See Fig.3 page No. 13). • Excellent lateral spring characteristics, as desired.
- Achieved by variation in effective area in lateral direction (See Fig.3 page No. 13).
• Avoids excess air consumption due to instantaneous modes of vehicle oscillation or change in air pressure. - Achieved by designing delayed reaction levelling valve (See Fig.4 page No. 14).
6. CONSTRUCTION DETAILS:
• Construction details of air spring are shown in (See Fig.5 page No. 15). (air spring with outside emergency spring), & Fig. 6 at page no.16 (air spring with inside emergency spring).
7. SCHEMATIC LAYOUT OF PNEUMATIC SUSPENSION CONTROL EQUIPMENTS:
A schematic layout of pneumatic suspension control equipments has been provided in Fig.7 at page no. 17.
8. MODIFICATION FOR FITMENT OF AIR SPRING IF REQUIRED: 8.1 Bogie Frame & Suspension:
• Air spring has been installed at secondary stage replacing steel coil springs. • A fixed lower spring beam (as cradle) to accommodate the air spring has been provided
on bogie bolster. • A lateral hydraulic damper and lateral bump stop have been provided at secondary stage. • Primary springs have been retained as steel spring. • Details are shown in Fig.8 at page no. 18 • Leveling valve provided between bogie frame and bogie bolster.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 6 of 21
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8.2 Bogie bolster:
• Provision made for air inlet to air spring. • 40 lit addl. Reservoir connected to each air spring is provided. • Duplex check valve is provided.
8.3 Under frame: • A pipeline is drawn from M.R pipe (feed pipe) for pneumatic suspension • One isolating cock, one non return valve, one 150 lit air reservoir (auxiliary reservoir) one
air filter and two separate isolating cocks to isolate each bogie have been provided • A schematic diagram is shown in fig.7 at page no 17.
8.4 BASE PLATE:
• Base plate to be used should be as per drawing No. RDSO sketch- K4018 alt ‘1’ is enclosed as fig.9 at page no 19.
9. OPERATING INSTRUCTIONS:
• Train Driver to maintain 7 bar pressure in compressor. • In case of heavy leakage of air from air spring system, Isolate the affected bogie and
observe speed restriction at 60 km/h up to the terminal point for maintenance. 10. DISMANTLING OF AIR SPRING FROM LOWER SPRING BEAM (CRADLE)
AND BOGIE BOLSTER:
• Remove All Body, Bogie connections • Remove duplex check valve from bolster • Remove lateral & vertical shock absorber • Remove equalizing rod connection from both ends of lower spring beam if provided. • Remove connection between arm of levelling valve & installation lever. • Remove all 4 No. Bolts and nut with the help of M16 Allen key and suitable spanner from
bottom plate of air spring & lower spring beam. • Lift bolster up to bogie frame to clear the spigot of air spring. • Slide air spring from lower spring seat.
11. INSPECTION & MAINTENANCE OF AIR SPRING: • Inspect for any water collection in rubber bellow of air spring • Inspect the air spring for any damage or leakage. • Inspect air spring seat and top plates for corrosion, if corrosion noticed is paint with
primer & black paint.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 7 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
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12. INSPECTION & MAINTENANCE OF LOWER SPRING BEAM:
• Inspect all welding joints of the lower spring beam (cradle) and repair if required. • Inspect air spring fixing holes of lower spring beam for elongation, if elongated build
them to dia.17 mm or dia. 26 mm. • Inspect the corrosion on top surface of lower spring beam, Remove the corrosion paint
with primer and black paint.
13. INSPECTION OF PIPE LINE:
• The air spring piping may be checked for any leakage/damage by soap test and repair if required.
14. MOUNTING AIR SPRING ON LOWER SPRING BEAM AND BOLSTER:
• "O" rings provided on air spring spigot must be changed. • Mount air spring on lower spring beam and match the holes of bottom plate of air spring
and holes of lower spring beam. • Tight all 4 nut-bolts with the help of M16 Allen key and suitable spanner. • Place the bolster on air spring ensuring no damage to spigot of air spring. • Connect levelling valve arm with installation lever. • Mount vertical and lateral shock absorber. • Connect all flexible/fixed pipe connections of bogie • All the threaded joints of air spring be sealed with thread sealing tape to avoid air leakage. • The filter of levelling valve must be cleaned.
15. TEST FOR LEAKAGE:
• Connect the hosepipes on the under frame piping with the levelling valves of the bogies. • Connect pressure gauges to the drain plug locations of 150-litre reservoir. • Provide packing in the gap between bolster & bogie frame. • Connect the 150-litre reservoir on the under frame to the compressed air source of
pressure 9.0 kgf/cm2. • Allow air into the air springs to a value of 9.0 kgf/cm2 in the pressure gauge by adjusting
the horizontal lever of the levelling valve and keep it in the same position. • Close the isolating cock connecting MR pipe with 150-litre reservoir. • Test all pipe joints for leakages. • Check the pressure gauge readings after one hour. The pressure drop should be within 1%
of the test pressure 9.0 kgf/cm2. • Release the air completely by dropping the horizontal lever. • Remove the packing.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 8 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
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16. PROCEDURE FOR CHECKING BOGIE CLEARANCES ON AC AND NON AC COACHES PROVIDED WITH AIR SPRINGS :
• Firstly find out the type of bogie as AC EOG (16 T), AC SG (16T), or NON AC (13 T) coaches and make RCF or ICF. List of relevant drawings are as under: TYPE OF COACH ICF DRAWING No. RCF DRAWING No. AC EOG(16 T) WTAC5-0-0-501
(ANNEXURE.-C) -
AC SG(16 T) LWGSCWAC-0-0-001 (ANNEXURE.-D)
CA00001(ANNEXURE.-F)
NON AC (13 T) LGS-0-0-001 (ANNEXURE.-E)
CA00002(ANNEXURE.-G)
• Than the coach should be placed at leveled track. • The primary springs should be grouped as per ICF drawing no. ICF/STD-9-0-003 placed at
Annexure-H, in which the different type of primary springs is grouped for air spring bogie and other type of bogie.
• The primary springs are used for the air spring bogies as follows: TYPE OF COACH ICF DRAWING No. RCF DRAWING No. AC EOG(16 T) WTAC-0-1-202 WTAC-0-1-202 AC SG(16 T) WTAC-0-1-202 AW01101 NON AC (13 T) WTAC-0-1-202 CC01129 POWER CAR WLRRM8-0-1-801 -
• Place the proper primary springs and compensating rings in AC EOG,AC SG and NON AC coaches with air spring bogie as per following suspension diagram: TYPE OF COACH
ICF DRAWING No. RCF DRAWING No.
AC EOG(16 T) WTAC5-9-0-501(ANNEXURE.-I) - AC SG(16 T) - CA90001(ANNEXURE.-J) NON AC (13 T) - CA90001
• Than maintain the bogie corner heights as per relevant suspension diagram. • After the bogie corner height is maintained, adjust the air spring height as per relevant suspension
diagram with the help of installation lever.
17. PROCEDURE FOR CENTRE BUFFER COUPLER HEIGHT ADJUSTMENT IN WORKSHOP: • After POH and before assembling the bogie, measure the wheel diameter. • Depending upon the wheel diameter, place wooden packing of required thickness under the
flange of lower spring seat as indicated in the following table: Average wheel dia. between the two wheels on the same bogie
Thickness of hard packing ring (mm)
889 mm to 864 mm 13 863 mm to 840 mm 26 840 mm to 820 mm 38 819 mm 48
Ref: CGW 0001,Rev.-3 Date / Month of issue:
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18. INSTALLATION LEVER ADJUSTMENT:
Adjustment of installation levers is essential for proper levelling of coach body. The adjustment needs to be carried out in AOH/POH or intermediate dismantling of levelling valve system. The procedure to be followed is as under: • Keep the coach on a level track. • Connect pressure gauges to the drain plug locations of all 40-litre reservoirs in the bogie. • Place the car body on the two bogies and hook it up to the air supply (by opening the
isolating cock 1a). • First open only the isolating cock (1c0, thereby releasing the air supply for bogie “1”and
affix the level control rod assembly to the valves). • On the rod assemblies (6) set the general level (-5mm) that the car body is ultimately to
have above the bogie frame and the upper edge of the bogie. • Insert the suitable block (ca 10 mm under the nominal height and preferably of hardwood)
centrally between the bogie frame and the car body and lower the car body onto the block by removing the valve rod assembly (6).
• Shut the isolating cock (1c) again, thereby interrupting the supply of air to bogie“1” and open isolating cock (1b), and thereby releasing the air supply to bogie “2”.
• Affix level control rod assemblies (6) to the valves (5) and set the assemblies (6) to desired level.
• Insert a suitable block (preferably hardwood) centrally between the bogie frame and the car body and lower the car body onto block by removing the valve and assemblies (6).
• Shut isolating cock (1b) again, thereby cutting off the air supply to bogie “2” and open isolating cock (1c), and thereby releasing the air supply to bogie “1”.
• Attach level control rod assemblies (6) to the valves (5) and, after aeration, carefully adjust settings on both rod assemblies (6) simultaneously (proceeding from below) until the desired car body height has been attained.
• Remove the block from bogie “1”. • Reopen isolating cock (1b), thereby releasing air to bogie “2”, and while at the same time
hanging the rod assembly (6) back in place in bogie “2”. • Remove the block from bogie “2”. • Recheck the height at all measuring points. CAUTION: If the difference in pressure of the air in the air springs of the same bogie is more than setting pressure of the duplex check valve i.e. 1.5 bar, then the air will continuously escape from one air spring to the other through the duplex check valve and then to atmosphere. • Tighten the installation lever lock nuts with the horizontal lever, so that the setting will
not be disturbed. • Repeat the above procedure for the second bogie. • Disconnect the pressure gauges and replace the drain plugs.
19. CHARACTERISTICS OF AIR SPRING / PERIODICAL INSPECTION OF AIR SPRING
SYSTEM ON MAINLINE COACHES:
These are provided at Annexure – A and B for reference and implementation.
Ref: CGW 0001,Rev.-3 Date / Month of issue:
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20. AIR SPRING SERVICE: For the maintenance of the air springs, the respective vendors maintenance manuals should be followed. These maintenance manuals shall be provided by the respective vendors at the time of delivery of air springs.
21. AIR SPRING CONTROL EQUIPMENT SERVICE:
For the maintenance of the air springs control equipment, the respective vendor’s maintenance manuals should be followed. These maintenance manuals shall be provided by the respective vendors at the time of delivery of air spring control equipments.
-------------------------------------
Ref: CGW 0001,Rev.-3 Date / Month of issue:
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Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
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WORKING PRINCIPLE OF PNEUMATIC SUSPENSION
FIG. NO. 1
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 12 of 21
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FIG
. No.
2
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 13 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-13
FIG
. No.
3 V
ER
TIC
AL
AN
D L
ATE
RA
L A
CTI
ON
OF
AIR
SP
RIN
G
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Page 14 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
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DEL
AY
ED R
EAC
TIO
N O
F C
ON
TRO
L V
ALV
E TO
AV
OID
EX
CES
SIV
E A
IR C
ON
SULA
TIO
N
FIG
. N
o.
4
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 15 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-15
FIG.
NO
. 5: A
IR S
PRIN
G W
ITH
OU
TSID
E EM
ERG
ENC
Y SP
RIN
G
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 16 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-16
FIG.
NO
. 6 :
AIR
SPR
ING
WIT
H IN
SID
E EM
ERG
ENC
Y SP
RIN
G
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 17 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-17
FIG.
NO
. 7: S
CH
EMAT
IC D
IAG
RA
M O
F A
IR S
USP
ENSI
ON
EQ
UIP
MEN
TS
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Page 18 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
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CR
ADLE
FIG.
No.
8 :
BO
GIE
GEN
ERA
L A
RR
AN
GEM
ENT
WIT
H A
IR S
PRIN
G R
ETR
OFI
TMEN
T
Ref: CGW 0001,Rev.-3 Date / Month of issue:
Page 19 of 21
Maintenance Instruction No. September, 2009 CMI- RDSO/2009/CG/CMI-01
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FIG No. 9 : BASE PLATE FOR AIR SPRING
Ref: CGW 0001,Rev.-3
Date / Month of issue: September, 2009
Page 20 of 21
Maintenance Instruction No.
CMI- RDSO/2009/CG/CMI-01
RDSO/Lucknow Page-20
ANNEXURE-A
GENERAL TECHNICAL DATA AS PER RDSO STR C-K509
1. STATIC VERTICAL LOADS ON AIR SPRING
Tare load -------------------------- -- 50.0 KN Full load --------------------------- -- 140.0 KN
2. VERTICAL STIFFNESS
At dz + 20 mm and constant speed of 5mm/sec, the vertical stiffness (Cz) shall be:
Vertical stiffness Cz IN N/mm Load in KN (Static) Additional Volume 20dm3 Additional volume 40dm3
50 550±50 N/mm 400±50N/mm 115 875±75N/mm 625±75N/mm 140 1000±100N/mm 700±100N/mm
3. HORIZONTAL STIFFNESS
At dy +20 mm at constant speed of 5 mm/sec, the lateral stiffness (Cy) shall be:
Load in KN (Static) Lateral stiffness Cy IN N/mm 50 150 ±25 N/mm 115 175±25 N/mm 140 200±25 N/mm
4. Min. height of air spring under full load with no air and without spigot - 210 mm
5. Installed height without spigot - 255+0-5 mm.
Ref: CGW 0001,Rev.-3
Date / Month of issue: September, 2009
Page 21 of 21
Maintenance Instruction No.
CMI- RDSO/2009/CG/CMI-01
PERIODICAL INSPECTION OF AIR SPRINGS SYSTEM ON MAINLINE COACHES EXISTING
SCHEDULE OF INSPECTION
INSPECTION ON AIR SPRING SYSTEM
INSPECTION
SITE Primary / Secondary
• Visual check: General conditions which includes any external damages, air leakage, infringement of any fittings, etc.
• Draining of 150-liter air reservoir of air spring • Check the position of isolating cock and drain cock, these should be on and off position respectively.
Pit line
Schedule-A • As in Primary / Secondary schedule and Draining of 40-liter reservoir. • Cleaning of leveling valve filter as per manufacturer’s manual. The procedure is shown at Annexure B/1.
Pit line
Schedule -B • As in Schedule -A • Checking of installation lever with inflated air spring for normal function, tightening of installation lever
nuts and protection screen nuts, tightening of bracket of all flexible hoses. • Cleaning of air filter of 150-liter reservoir.
Pit line
Schedule -C • As in Schedule -B & • Thorough checking of air spring, bulging of bellow, air leakage. • Air suspension pipe leakage check by using soap water. • Removing dust mud & oil deposit if any, on air spring and control equipment. • Thorough checking of lower spring beam for any crack and deformation. • Tightening of air spring bottom plate bolts and nuts. • Measurement of bogie clearances related to air spring.
Sick line
AOH/POH • As in Schedule - C and • Through visual check of air spring as per Annexure-C or D after dismantling as in clause 10. • Remove all valves and carry out external cleaning, overhauling and function test should be done as given
in maintenance manual supplied by respective vendors. • Checking securing arrangement of steel pipeline. • Leakage test of air springs as per clause 15. • Installation lever adjustment as per clause 18. • Lateral damper condition should be checked and replace with fresh if damaged. • Air spring bellow should not be painted.
Depot/ Work shop
AN
NEX
UR
E-B
RDSO/Lucknow Page-21
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 3 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 3 of 33
CONTENTS
Description Page I FOREWORD … … … … … … … 3 II AIR SPRING ASSEMBLY ( SECTION – A )
1. Scope … … … … … … … 5 2. Operating Conditions … … … … … … … 5 3. Environmental Condition … … … … … … 6 4. Scope of Supply … … … … … … … 6 5. Procedure For Vendor Registration… … … … … 6 6. Technical Requirements … … … … … … 8 7. Submission of Offer … … … … … … … 10 8. Guarantee … … … … … … … 11 9. Installation, Commissioning, & Maintenance … … … 11 10. Inspection and Testing … … … … … … … 12 11. Marking … … … … … … … 14 12. Packing … … … … … … … 14 13. Maintenance Manual … … … … … … … 14 14. Clarification … … … … … … … 14 ANNEXURE-A … … … … … … … 15 to 17 ANNEXURE-B … … … … … … … 18
III EMERGENCY RUBBER SPRINGS ( SECTION – B ) 1. Scope … … … … … … … 19 2. Requirements … … … … … … … 19 3. Stiffness Characteristics … … … … … … … 20 4. Testing of Emergency Rubber Spring … … … … … 20 5. Bonding Strength Test … … … … … … … 21 6. Vertical Load vs Deflection Test (Before Endurance Test) … … 21 7. Shear Load vs Deflection Test (Before Endurance Test) … … 21 8. Endurance Test … … … … … … … 22 9. Vertical Load vs Deflection Test (After Endurance Test) … … 23 10. Shear Load vs Deflection Test (After Endurance Test) … … 23 11. Superimposition of Acquired Data 23 12. Creep Test … … … … … … … 24 13. General … … … … … … … 24
ANNEXURE – I to VII … … … … … … … 25to 31 DRAWINGS 1. SKETCH –K4018 alt.1 : Base Plate of Air Spring … … … 32 2. SKETCH –K4017 : Space Envelope for Air Spring … … … 33
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 4 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 4 of 33
FOREWORD
This Schedule of Technical Requirements (STR) spells out the schedule of technical requirements of Air Spring of 140kN Capacity and Metal Bonded Emergency Rubber Spring for BG (1676mm) Main line / Rajdhani coaches having ICF type bogies.
This Schedule of Technical Requirements consists of Section-A and Section-B. Section-A is concerned with the entire Air Spring Assembly whereas the Section-B contains details of the requirements and tests for the Emergency Springs.
This Schedule of Technical Requirements supersedes specification No.C-K509 Rev.1.
The specification shall not be altered /modified or reproduced in any form without the written permission of the Director General (Carriage), RDSO, Lucknow.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 5 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 5 of 33
( SECTION - A )
SCHEDULE OF TECHNICAL REQUIREMENTS OF
AIR SPRING ASSEMBLY FOR MAINLINE ICF COACHES 1. SCOPE: 1.1 This schedule lays down the technical requirements for the design and supply of air
spring assembly for fitment in the existing two axle ICF Bogie having end on generation or self generation system in Mainline / Rajdhani coaches of Indian Railways. Scope of supply shall generally be as per clause 4 of this Schedule of Technical Requirements (STR). However, if the supplier feels that certain additional items are necessary for improved working performance of the system, he may quote for the same. In any case, purchaser will be at liberty to buy all or part material from the offer.
1.2 Control equipment for the air spring assembly should be supplied to RDSO’s STR C-
K407 (Latest Version). The air spring assembly should be compatible with the control equipment described in the above STR. The purchaser will be at liberty to buy any part or complete control equipment to STR C-K407 (Latest Version) and air spring assembly to this STR from different source of supply.
2. OPERATING CONDITIONS: 2.1 Each coach fitted with air spring assemblies would have a feed pipe and one brake pipe.
Normally up to twenty six coaches form a train. These coaches would have a maximum speed of 160 kmph and negotiate curves upto a minimum radius of 175 meter and carry payload upto 16 t.
2.2 Compressed air supply to the air spring assemblies shall be maintained through a
compressor provided in the Locomotive. The Locomotive compressor charges the Feed pipe at 6 Kg/cm². Provision of air-drying does not exist in some of the compressed air supply system. Pneumatic circuit of air spring assembly system is connected to the Feed pipe.
2.3 Each coach shall be fitted with four air spring assemblies (two per bogie) and each air
spring assembly shall be controlled by an independent levelling valve (4-point control system). Two air springs of the same bogie shall be connected through a duplex check valve set to act at a pressure differential of 1.5 + 0.12 Kg/cm².
2.4 To maintain continuous supply of compressed air to the air spring assembly system, a
150-litre auxiliary air reservoir has been provided. 2.5 Track-ballast during train operation may occasionally hit the air spring assembly and
control equipments.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 6 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 6 of 33
3. ENVIRONMENTAL CONDITIONS: 3.1 Air suspension fitted in of mainline having end on generation or self generation system
shall be subjected to following environmental conditions:
Max. Temperature under sun : 60ºC. Ambient temperature : 0º to 45ºC in shade. Average relative humidity : 70% to 90%, 100% on several days. Rainfall : Fairly heavy, maximum being 200mm in
24 hours, typical to the coastal areas. Atmosphere : Dusty for several months of the year. 3.2 Air spring assembly system may also come in contact with the following, during coach
maintenance operation:
• Chemical products (like cleaning compound of coach cleaning) • Cotton waste smeared with oil and paint etc. • Disinfectants. • Oils & lubricants used in coach bogies.
4. SCOPE OF SUPPLY: 4.1 The scope of supply covers the following items:
i) For each air spring assembly: S.No. Item Quantity
1 Air spring (Rubber bellow) 1 2 Top interfacing plate with bolster,
with spigot 1
3 Sealing O-rings 2 4 Base plate 1 5 Emergency spring 1 6 High tensile hex. socket Head screws
with spring washers 4 sets
ii) Any other item, which in the view of the supplier is considered essential for operation or enhances the performance of the system, may also be offered.
5. PROCEDURE FOR VENDOR REGISTRATION: 5.1 Vendors willing to supply air spring assembly for the use of Indian Railways shall register
themselves with Research Designs and Standards Organization, Ministry of Railways, Lucknow-226011 (RDSO) and should be ISO approved.
5.2 The Vendor shall have a well-documented ‘Internal Quality Assurance System’ to ensure
sustained quality of product being manufactured. The Quality Assurance System’ shall generally cover the following:-
5.2.1 System to ensure that correct raw material is being used. The type of rubber used for the
air spring bellow shall be specified by the OEM. 5.2.2 System to ensure that components having manufacturing defects are identified and
destroyed so that such components are not used during assembly of air spring.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 7 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 7 of 33
5.2.3 System to ensure that bought out components are strictly as per requirements laid down in the STR / drawing.
5.2.4 System to maintain strict control of dimensions and workmanship of components and
assembled product. 5.2.5 System to test and establish that the air spring assembly manufactured by the firm meets
all the requirements laid down in STR / drawing. 5.2.6 System of periodical calibration of equipments/gauges to ensure accuracy of product. 5.2.7 System to ensure cleaning & removal of dust/rust and moisture by dry air. 5.2.8 System to ensure that air spring assembly is properly packed to meet the requirement of
Clause-12 of this STR. 5.2.9 System to ensure traceability at least up to guarantee period. 5.3 Special Conditions:
a) Air spring vendors shall be recognized on the basis of the OEM design. An OEM for this purpose shall be defined as a company having the facilities for designing the air spring and the necessary infrastructure to carry out detailed type tests at their own facility. Their air spring designs should have been approved over other railway systems and been in regular passenger service.
b) Application for registration shall therefore be considered from OEMs or from
companies entering into a valid MOU/Agreement with OEM air spring manufacturers as defined above. The MOU should clearly state that the OEM undertakes to fulfill the warranty and support obligations with respect to technology upgradations as and when required for the air spring assembly, even in case the MOU is rescinded at some later stage.
c) Since air springs are a safety related suspension element, in-service trials shall
be necessary for each OEM design before full clearance is given for supply. d) OEMs whose air springs have completed five years satisfactory service on other
Railway Systems on at least two hundred fifty coach sets shall only be considered. Vendors shall be required to submit verifiable documentary proof of satisfactory performance of the same. The air springs of a particular design shall be subjected to in-service trials on a minimum of ten coach sets for one year on IR’s system. An OEM air spring design shall be treated as developmental during the period of service trials.
e) In case of any failure during service trials attributable to poor design or material,
the service trials shall be repeated. RDSO shall decide the cause of failure after investigation in this regard.
f) After completion of service trial period, a sample of the air spring shall be
subjected to the tests laid down at paras 10.2, 10.3 and 10.4. In case these values are beyond permissible limits, the air spring design shall be deemed to have failed the service trials.
g) Vendors providing a particular OEM design as defined at (a) above shall be
provided part-II status on successful completion of service trials as defined above.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 8 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 8 of 33
A Vendor shall be considered eligible for upgradation to Part-I status on completing successful supply of a minimum of 100 coach sets of the particular
type of air spring and also after a minimum period of 18 months after issue of first Inspection Certificate as a Part-II vendor.
h) In case any part of the air spring assembly is manufactured outside India, a
certificate of country of origin shall be provided with each supply clearly establishing the source of manufacture. Source of manufacture of each component shall be provided by the vendor at the time of design approval.
i) After type tests of a particular OEM design are approved by RDSO, vendors shall
ensure that air springs to the particular specification are supplied with components manufactured from the sources as indicated at the time of design approval and used for type testing. In case design/source of any component of the air spring assembly is changed, fresh type tests and service trials shall be necessary.
6. TECHNICAL REQURIEMENTS: 6.1 Static load & pressure per air spring assembly: 6.1.1 The air spring assembly shall be capable of withstanding following range of static vertical
loads by using compressed air with a limiting pressure value of 6 Kg/cm². i) Minimum Tare load = 50 KN ii) Maximum Full load = 140 KN Further, the air spring assembly should be capable of meeting the maximum vertical load at an air pressure of 5.5-5.8 Kg/cm2 to allow for minor pressure drops along the train length during run.
6.1.2 It shall be possible to inflate the proposed air spring assembly from its deflated condition when pre-loaded with a static vertical load of upto 140 KN (max.), simply by supply of compressed air through levelling valve without any other external assistance.
6.2 Deflection characteristics of air spring assembly: 6.2.1 During dynamic (running) condition of coaches, the air springs shall be subjected to the
following deflections at frequencies of upto 3Hz. The design of the spring should be able to cater for the same: i) Max. Vertical deflection of spring (dz.) = ± 30 mm ii) Max. Lateral deflection of spring (dy.) = ± 60 mm
6.3 Air spring assembly shall be designed for use with an additional air reservoir of volume
20 or 40 dm³ permanently connected to air spring. 6.4 Vertical stiffness of air spring assembly: 6.4.1 Minimum air cushion provided under minimum tare load condition shall be 25 mm, with
installed height of 255+0-5 mm.
6.4.2 At dz + 20 mm at constant speed of 5mm/sec, the vertical stiffness (Cz) shall be:
Vertical stiffness Cz IN N/mm Load in KN (Static) Additional Volume 20dm3 Additional volume 40dm3
50 550±50 N/mm 400±50N/mm 115 875±75N/mm 625±75N/mm 140 1000±100N/mm 700±100N/mm
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 9 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 9 of 33
6.5 Lateral spring stiffness of air spring assembly:
At dy +20 mm at constant speed of 5 mm/sec, the lateral stiffness (Cy) shall be:
Load in KN (Static) Lateral stiffness Cy IN N/mm 50 150 ±25 N/mm
115 175±25 N/mm 140 200±25 N/mm
6.6 The spring should be able to withstand an occasional 50% dynamic augment over the
maximum static load. 6.7 Bursting strength of the air spring:
Air spring shall be capable of withstanding a minimum bursting pressure of 30 Kg/cm². Test procedure for check bursting strength of air spring should be as follows. This test shall be performed with water at an ambient temperature above or around 200C.
- Install the air spring assembly that was subjected one million cycles endurance test at design height.
- Inflate the air spring assembly with minimum 30 kg/cm2 internal pressure and hold the air spring assembly at this pressure for a minimum of 5 minutes.
- Observe if there is any damage or visible crack.
6.8 In case of accidental deflation of the air spring assembly during dynamic condition of the coach due to reasons other than leakage/bursting/puncture etc. of the air spring, when the coach sits on emergency springs (Clause 6.9.3), there shall be no damage to air spring assembly under normal operating conditions.
6.9 Emergency spring: 6.9.1 During train operation, deflation of an air spring due to depletion of pneumatic pressure
either on account of leakage or disruption in air supply cannot be ruled out. 6.9.2 To counter such situations, an emergency rubber spring shall be required to be installed
in the air spring assembly, which shall act as suspension element during such happenings.
6.9.3 This spring shall be capable of safely carrying the affected vehicle as above (either fully
or partially loaded) for a minimum distance of about 1000 Km at speed of at least 60 kmph under normal operating conditions without suffering any self-damage or any further damage to the air spring which will make them unfit for further use. This situation is likely to arise occasionally in the service life of the air spring.
6.10 Space Constraints:
Air spring assembly consisting of top plate with spigot (for air connection), air spring bellow, rim, external emergency rubber spring, base plate etc. in inflated condition shall be within the space envelope shown in RDSO Drawing CG-K4017. Some of the leading parameters of air spring assembly in inflated condition shall be:
i) Installed height without spigot = 255+0
-5 mm. ii) Maximum permissible diameter of air spring, = Ø 740 mm.
iii) Maximum permissible external diameter of top plate of air spring = Ø 750 mm.
iv) Min. height of air spring under full load with no air and without spigot = 210 mm
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 10 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 10 of 33
6.11 Pneumatic supply connection:
Air inlet connection point to the air spring shall be located at the centre of top plate through a spigot made air tight by using minimum two rubber O-rings. The dimension of spigot shall be as under: i) Outer diameter = Ø 85-0.036
-0.071 mm. ii) Height = 35 + 0.5 mm. iii) Diameter of “O” ring = 5.7 + 0.1 mm.
6.12 Mounting arrangement:
The base plate of air spring assembly for mounting shall be provided as under:
(i) Four equally spaced holes of diameter Ǿ17mm at distance of 325 mm on a square plate. High tensile hexagonal socket-head screws M16 X 45 long, to IS: 2269 class 8.8, spring washer A 16 IS: 3063 and nuts (prevailing torque type) B M16 to IS: 7002 class 8.
The mounting arrangement has been shown in RDSO Drawing: CG-K4018 Alt-1. All black oxide coated bolts/ nuts shall be used for securing the assembly to the bogie.
6.13 Other Details:
All metal parts of the air spring assembly shall be of stainless steel or corrosion resistant steel Grade E 250 Cu Fe 410 WB to IS: 2062 (latest year of issue) or equivalent duly painted in red. The fasteners shall be of high tensile steel to IS: 2269 (ISO 898) and shall be zinc coated.
6.14 Physical tests of air spring bellow :
Physical tests of the air spring bellow as specified at para. 5 of Annexure “A” of this specification shall form a part of the type test report. These tests shall be confirmed at an Indian Laboratory at a maximum interval of three years. RDSO reserves the right to carry out these tests earlier. The cost of these tests shall be borne by the vendor.
7. SUBMISSION OF OFFER: 7.1 Firms desirous of seeking approval from RDSO for supply of material as per this STR,
shall submit their proposal accompanied by the documents containing the following information to RDSO :-
1) Dimensional drawing of air spring assembly and emergency spring. 2) Inner volume, effective area and effective diameter of springs. 3) Weight of one air spring assembly. 4) Whether proposed air spring is being used by any other rail-road system? If yes,
details regarding quantity, type of stock, max. operating speed, type of service, average annual running kilometers, life cycle obtained by the user rail-road and maintenance cycle followed by them shall be furnished.
5) Details of deviation from the STR. 6) Content of indigenous and imported items in offered air spring assembly.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 11 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 11 of 33
7) Expected life cycle in operating and environmental conditions enumerated in clause 2 & 3.
8) MOU / Agreement with the OEM permitting supply/manufacture of the offered
springs. (For proposals from other than OEMs). 9) A write-up giving broadly the maintenance requirements on time/distance basis
along with the facilities that would be needed for proper maintenance/upkeep of the offered air spring assembly.
10) A detailed write-up giving the details of "Quality Assurance System" being
followed for manufacture of the offered items; and 11) Details of manufacturing and testing facilities available with the manufacturer.
7.2 The information as received above shall be used for preliminary evaluation of the firm's capability in meeting with the requirements of this STR.
7.3 The firm shall be required to submit a Type Test Report of a proposed design after the
preliminary evaluation carried out as per para 7.2 is found satisfactory. Type Test Report shall be complying with Annexure “A” of this STR.
7.4 The premises of the firm shall be visited by RDSO's officials for on-the-spot assessment
of the firm's capability after the Type Test Report is accepted by RDSO. 7.5 RDSO reserves complete right in granting approval or otherwise to a firm. 8. GUARANTEE: 8.1 Complete air spring assembly including emergency spring shall be guaranteed for
satisfactory performance for a minimum period of 60 months from the date of actual commission in bogies or 72 months from the date of supply. Satisfactory performance for this purpose means that complete air spring assembly or any of its part shall neither show any kind of deterioration which is likely to render it unserviceable nor lose its characteristics as stipulated in this STR, during the guarantee period for reasons attributable to manufacturing/design defects.
8.2 In the event of 'non-satisfactory performance' of any of the items as indicated above,
supplier will have to replace the same at his own expense without levying any cost involved in transportation, handling and replacement of such items on the Purchaser.
9. INSTALLATION, COMMISSIONING & MAINTENANCE: 9.1 On placement of order, supplier whose equipment will be purchased for the "First Time"
for installation on the coaches, shall have to depute his representative at his own expense to associate with the purchaser in installation and commissioning of the equipment on the first five coaches. He shall also depute his representative during maintenance schedules undertaken on his equipment as per maintenance booklet supplied by him.
9.2 With every order for supply of the air spring assembly, the supplier shall have to supply
maintenance instructions in the form of two booklets (hard copy) and one copy on Compact Disc (MS-Office compatible).
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 12 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 12 of 33
9.3 Maintenance booklet supplied by the supplier shall cover the following aspects in detail:
1) Specification of the air spring assembly. 2) Working principle based on the actual construction. 3) Constructional details giving sketches, drawings and photographs etc. identifying
various items and their part numbers etc. for easy identification. 4) Procedure for dismantling using sequential steps with the help of sketches. 5) Procedure for assembly, using sequential steps with the help of sketches. 6) Jigs, tools, other materials and details of special set-ups etc., necessary for item 4
& 5 above. 7) Testing procedures and facilities required along with their details. 8) Comprehensive details containing legible sectional views of defects normally
observed or may happen on air spring and emergency spring with clear remarks whether the defect is rejectable or non-rejectable.
9) List of other defects and their remedies. 10) Periodicity for various maintenance activities on time and distance basis. 11) Do's and Don'ts for maintenance officials.
10. INSPECTION AND TESTING: 10.1 General requirements:
During initial approval of a firm by RDSO (Clause 7) and later on when approval has been granted, RDSO for purpose of ensuring quality of purchased product may carry out periodic quality audit, inspection and testing of the equipment at the premises of the manufacturer. Purchase inspection shall be done at the premises of the manufacturer by a representative of the Research Designs and Standards Organization or an agency authorized by RDSO. The supplier shall have to arrange for the following and associate with the same:
1) Access to all records considered relevant for such activity by inspecting officials. 2) Questioning of relevant personnel engaged in production, testing and quality checking
activities etc. or related issues. 3) Testing of few samples of items already produced by the firm to ascertain the technical
characteristics given in this STR.
4) Any other check considered necessary by the inspecting party.
5) The inspecting official shall carry out purchase inspection as per inspection check list attached at Annexure “B” of this STR.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 13 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 13 of 33
10.2 Inspection and testing of air spring assembly (air bellow and emergency spring): 10.2.1 Dimensional check:
ITEM REFERENCE DOCUMENTS Air spring
Top Plate with spigot “O” Ring Base plate
As per Firm’s assembly drawing approved by RDSO & technical requirements of clause 6 of
this STR.
10.3 Leak test of air spring bellow:
Leak test of air spring assembly shall be carried out as follows- - Install the air spring assembly at design height. - Gradually raise the air pressure to 9 kg/cm2 and disconnect the air supply. - Air spring assembly shall be checked for pressure drop at the following pressure
and time intervals. a) After one hour at internal pressure 9.0 kg/cm2. b) After 15 minutes at internal pressure 6.0 kg/cm2. The above tests shall be
conducted with the air supply and drain system of test device turned off. Drop of pressure at the completion of test shall be measured. The pressure drop is required to be within 1% of the test pressure i.e. 9.0 kg/cm2 or 6.0 kg/cm2 as applicable.
10.4 Characteristics tests: 10.4.1 Air bellow:
Air spring assembly at fixed installation height 255 mm (with additional volume of air 40 dm2) shall be tested at pressure starting from 1, 2, 3, 4, 5 and upto 6 kg/cm2. The recordings shall be done as given below:-
Observed Load in kN S.N. Pressure in Kg/cm2
Specified Load in kN Spg.No. Spg No. Spg.No. Spg.No.
10.4.2 Emergency spring/ bumper: Load vs. Deflection characteristics measured at vertical loads on Emergency spring/bumper given in approved type test report and approved by RDSO.
10.5 10% samples of the lot or a minimum 10 samples shall be picked up randomly for
dimensional & other specified inspections as given in clause 10.2.1 of this STR. 10.6 For other specified inspections a given in clause 10.3 and 10.4 of this STR, samples shall
be picked up randomly as under:
Lot size upto 10 25 50 75 100 No of samples 2 3 4 5 6
For lot sizes more than 100, 6% of the samples shall be picked up randomly for the above inspections.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 14 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 14 of 33
10.7 In case any picked up sample fails, manufacturer/supplier shall re-offer, rectifying the defects. However, in such cases, double the quantity of samples shall be picked up and shall be checked for dimension and other specified testing. In case any one sample fails again, the entire lot shall be rejected.
11. MARKING:
Every item of the air spring assembly shall be legibly marked to indicate the following: 1) Manufacturer's initials. 2) Month and year of manufacture. 3) Identification marks, i.e. Part Number, Batch Number, etc.
12. PACKING:
The air spring assembly shall be suitably packed along with its loose parts and exposed threaded portion, to protect against any damage that may occur during transit and handling. The opening of the spigot of the spring shall be suitably covered with a plastic/rubber cap to prevent ingress of dust or foreign material in the air spring.
13. MAINTENANCE MANUAL: The supplier shall provide at least one copy free of cost for each consignment, a detailed
maintenance manual for maintenance and overhaul purpose. 14. GENERAL: 14.1 RDSO may draw samples for quality check to test any property mentioned in this
specification at it’s discretion. The vendor shall arrange testing of these samples at a reputed outside laboratory as decided between RDSO and the vendor. The testing charges should be borne by the vendor.
14.2 Additional information if required may be obtained from the office of the Director General
(Carriage), RDSO, Manak Nagar, Lucknow – 226011.
==============
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 15 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 15 of 33
Annexure – A
REQUIREMENTS OF TYPE TEST REPORT
The type test report of air spring assembly shall consist of the following, clearly represented by graphs as well as in tabulation forms, with detailed test procedures and their results: - 1) Lateral characteristics measurement at 50,70, 115 & 140 KN vertical loads with additional
volume of air 20, 30 & 40 liters and lateral stroke dy = ±10, ±20, ±30, ±40, ±50, ±60 mm, speed V= 5 mm/sec, using triangular wave form of vibrations in lateral direction.
2) Vertical characteristics measurement at 50,70, 115 & 140 KN vertical loads with additional
volume of air 20, 30 & 40 liters, and vertical stroke dz = ±10, ±20, ±30mm, speed V= 5 mm/sec. using triangular wave form of vibrations in vertical direction.
3) Vertical force versus internal pressure characteristic measurements of air spring. 4) Effective area versus deflection curve of air bellow. 5) Physical tests of air spring bellow;
a) Abrasion test as per para. 6.2.5 of EN 13597 : 2003 (E).
b) Resistance to “Oil and Petroleum Product” as per para. 6.2.3 of EN 13597: 2003 (E). c) Adherence between plies as per para. 7.3.3 of EN 13597 : 2003 (E). d) Resistance to ozone test as per para. 6.2.2 of EN 13597 : 2003 (E).
6) Durability test at 6 Kg/cm² internal pressure (Endurance Test) of air bellow as follows.
ENDURANCE TEST OF AIR SPRING ASSEMBLY:
a) The endurance test is conducted to access suitability of the air spring assembly provided at secondary stage suspension in coach bogie by simulating service conditions
in the laboratory.
b) The test on air spring assembly shall be conducted only when the results of load deflection characteristics are obtained and found satisfactory.
c) The test shall be conducted in vertical and horizontal directions.
1) Vertical Endurance Test:
a) The air spring subjected to a pre compressive load equal to gross static vertical load as specified in para 4.1(Section- B) on an endurance testing machine by maintaining the design height of 255 mm and pressure of 6 kg/cm2.
b) With load given in para (a) above, the air spring assembly is subjected to vertical oscillation at sinusoidal frequency of 1.0 Hz and deflection of + 30 mm.
c) Endurance test shall be conducted for a total 1 million cycles at a stretch with conditions stipulated in para (a) and (b) above.
d) At the end of 1 million cycles following measurements/ observations shall be recorded after 30 minutes from load release.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 16 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 16 of 33
S.No. Parameters Result
1 Adhesion anomalies 2 Obvious sign of failure 3 Excessive wear or abrasion 4 Any visible crack or rupture
2) Shear Endurance Test:
a) The base plate of air spring assembly is clamped rigidly on a fixed horizontal table and
subjected to a vertical compressive pre load which is equal to gross vertical load as specified in para 4.1(Section - B) acting at the geometric centre of top plate, by maintaining the design height of 255 mm and pressure of 6 kg/cm2.
b) With load given in para (a) above, the air spring assembly is subjected to lateral displacement of + 30 mm at a sinusoidal frequency of 1.0 Hz in lateral direction.
c) Endurance test shall be conducted for a total 1 million cycles at a stretch with conditions stipulated in para (a) and (b) above.
d) At the end of 1 million cycles following measurements/ observations shall be recorded after 30 minutes from load release.
S.No. Parameters Result
1 Adhesion anomalies 2 Obvious sign of failure 3 Excessive wear or abrasion 4 Any visible crack or rupture
7) Burst pressure test of air spring bellow after endurance test, as per para 6.7 of part “A” of this STR.
8) Load versus deflection characteristics of emergency spring in vertical and lateral mode as
per paras 6 and 7 of part “B” of this STR. 9) Endurance test of emergency spring alongwith vertical and lateral characteristics for
minimum 1 million cycles, as per para 8 of part “B” of this STR. 10) Hysterisis loops of emergency spring in vertical mode with vertical pre load of 50,70, 115 &
140 KN. 11) Lateral characteristics (Load Vs. Deflection) of air spring assembly in no-air condition. 12) Material test report (supported by standard test specifications). 13) Any other test felt necessary by the manufacturer. 14) The type test should be repeated at the time of renewal of registration after first time
acceptance of a particular design of air spring assembly. 15) Leak test of air spring bellow as detailed at para 10.3 of part “A” of this STR. 16) Type test of emergency spring shall be carried out as detailed in Section – B of this
specification and reports as per annexure I to VII of Section – B of this STR provided with the same.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 17 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 17 of 33
17) Tolerance in different dimensions of air spring assembly should be mentioned in Type Test
Report and in drawing as under-
Fractions Decimals Angles
X.0 + 2
X.X + 1.0
X.XX + 0.50
X.XXX + 0.250
+ 3.0 0
18) Tolerance in measured values during characteristic tests should be mentioned in type test
report given as under:
S.No. Characteristic Tolerance 1 Pressure Force Characteristic + 5% 2 Load Deflection Characteristic + 10% 3 Stiffness under sinusoidal motion + 15%
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 18 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 18 of 33
ANNEXURE - B
CHECKLIST FOR INSPECTION OF AIR SPRING As per inspection and testing Clause no.10.0
1. Dimensional Check (10% of the Lot Qty.) SN Item Firm’s RDSO Approved Drg.No.
1. Top Plate 2. Spigot 3. Base Plate with fixing holes 4. “O” ring
2. Leak Test of Air Spring: As per Clause 10.3 of section A. SN Description Check whether with in
limit (√ / X) 1. Pressure at 9 kg/cm2 for 60 mins. 2. Pressure at 6 kg/cm2 for 15 mins
3. Load v/s Pressure Testing of Air Spring assembly: As per Clause 10.3 of section A. Test should be carried out as per the formats as below: S.N. Pressure in kg/cm2
or bar Specified Load (kN) Measured Load (kN)
1. 1 2. 2 3. 3 4. 4 5. 5 6. 6
4. Test for Emergency Spring: Load v/s Deflection Test. Test should be carried out as per the formats as below: S.N. Specified Deflection in mm (As
per Type Test Report) Specified Load in mm (As per Type Test Report)
Measured Deflection in mm
1. 2. 3. 4. Lot size for the tests at S. No. 2,3 & 4 above ate given as under:
Lot Size upto 10 25 50 75 100 Above 100 No. of Samples 2 3 4 5 6 6% of Lot
Check
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 19 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 19 of 33
( SECTION – B)
REQUIREMENTS FOR
EMERGENCY RUBBER SPRINGS USED IN AIR SPRINGS 1.0 SCOPE 1.1 This schedule of technical requirement (STR) Covers the technical requirements relating to material, constructions and tests for emergency rubber springs (metal bonded rubber bumpers) used in the air spring for BG EMU coach bogie having pneumatic suspension at secondary level. This does not include all the necessary provisions required for a supply contract.
1.2 This STR specifies the operating and performance requirement and method of testing the
emergency spring. These Emergency rubber springs are used in conjunction with the air below and are an integral part of air spring acting in series with the load and stiffness provided by compressed air inside the air bellow.
1.3 The emergency rubber springs are subjected to static and dynamic loading in compressive and shear modes simultaneously during operating conditions. The maximum compressive and shear loads are given in subsequent paragraphs.
1.4 The Emergency rubber spring shall be capable of withstanding wide climatic variation prevailing in the country without physical deterioration and change in compressive and shear stiffness characteristics.
2.0 REQUIREMENTS: 2.1 Material 2.1.1 Rubber:
The Emergency rubber bumper used in the air spring should be manufactured from natural rubber suitably compounded to conform to the requirements stipulated in STR.
2.1.2 Steel: a) The end mounting plates and inter leaves, shall be of steel conforming to IS 2062 Gr. Fe 410 Cu WB or stainless steel. b) In the preparation process of metal plates or inter leafs it shall be ensured that all sharp edges and burrs are removed and they are chemically treated and cleaned before shot grit blasting as per IS: 9139-GM30. 2.1.3 Bonding of Metal to Rubber: a) Before applying primer coat for achieving the required bond strength between metal part
and rubber, the metal parts which are ready for use should be stored suitably to avoid contamination on the surface.
b) The process and bonding agent adopted for bonding of rubber to metal plates shall be of proven quality.
c) The temperature and moulding time shall be optimized for proper curing of rubber. d) The rubber should be smooth and free from pinholes, blister and other visual flaws.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 20 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 20 of 33
2.2 Operating conditions: 2.2.1 The emergency rubber spring is an integral part of Air spring and acts in series with the
compressed air provided inside the air bellow, taking full load. 2.2.2 The maximum dynamic load on the air spring is 50% more than the static gross vertical
load. 2.2.3 Under deflated condition of air spring the Emergency rubber spring acts as bumper /
suspension and supports the full operating vertical and shear load at such lowerspeed which is considered safe as per standing criteria.
2.3 Environmental conditions: 2.3.1 Emergency spring being an integral part of air spring which is provided at secondary stage in mainline coaches is subjected to following environmental conditions:
Maximum temperature at sun 600 C Ambient Temperature 00 C to 450 C in shade Average relative humidity 70% to 90%, 100% on several days Rail fall 24 hrs. typical to coastal areas Atmosphere Dusty for several months of the years
. 3.0 STIFFNESS CHARACTERISTICS: 3.1 The vertical and lateral stiffness of emergency rubber spring can not be specified
precisely as it acts in series with the vertical and lateral stiffness provided by compressed air inside air bellow, under inflated condition of air spring and their reciprocal equivalence determines over all stiffness characteristics which is guided by STR for air spring system.
3.2 Under the deflated condition of air spring, the stiffness and damping of emergency spring is decided on transmissibility considerations which should be as minimum as possible at higher frequencies. However as a guide line the vertical deflection of Emergency rubber spring should not exceeded 10.0 – 15.0 mm under gross static load. (For details refer to the STR of corresponding air spring).
4.0 TESTING OF EMERGENCY RUBBER SPRING:
The emergency rubber spring unit (Bumper) comprising of bonded metal interleaf/ plates shall be subjected to following tests independently.
a) Bonding strength test. b) Vertical load Vs deflection test. (Before and after endurance test) c) Shear load Vs deflection test. (Before and after endurance test) d) Endurance test (vertical & lateral) e) Creep test. Test (b) and test (c) are required to be conducted before and after test (d)
4.1 Load conditions: 4.1.1 Static Vertical Loads The tare and gross vertical loads, on each air spring for different type of BG coaches are given as under.
S.No. Coach Type Tare Load Gross Load 1 Mainline Coaches (ICF Bogie) 50KN 140KN
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 21 of 33
STR No. C—K509, Rev.-2
RDSO/Lucknow. Page 21 of 33
4.1.2 Shear Loads The maximum operating shear load on each air spring for different types of BG coaches should be calculated as under: a) Max shear load = Maximum load (140 KN) X Max. friction coefficient Max. friction coefficient should be calculated in deflated condition.
OR b) Max. Shear Load = Max. value of (Lateral stiffness of air spring x Corresponding
def.)
Lateral stiffness should be calculated upto lateral deflection of 60 mm. For shear endurance test and shear load vs deflection test, the value of
maximum shear load may be obtained by both the above methods and used that value of shear load whichever is higher.
5.0 BONDING STRENGTH TEST:
The objective of this test is to determine bond strength between metal plate and rubber, under pre-determined load or deflection. This test is conducted as per IS: 3400 (Part – XIV). The bond should be capable of bearing a minimum stress level of 35 Kg/cm2.
6.0 VERTICAL LOAD vs DEFLECTION TEST: (Before Endurance test)
The rubber bumper should be subjected to three successive load cycles up to 150% of gross static vertical load as specified in para 4.1 at quasistatic frequency of 0.1Hz. for pre conditioning. In the fourth cycle the bumper shall be compressed with a load of 0.50 KN and the deflection taken as zero at this point. The fourth cycle is completed to record force Vs deflection curve in the form of hysterisis loop for a deflection range as obtained during initial three load cycle (loading and unloading). The load and deflection values shall be recorded digitally and the values shall be provided in the form of X – Y plot and digital table. (Ref. Annexure – 1). The following geometric parameter shall be recorded:
SNo. Parameters Before Endurance Test After Endurance Test * 1 Free height (mm) 2 Outer dia (mm) 3 Vertical axis orientation
(mm)
* Ref. Para 9.0 Vertical deflection in bumper should be given in tabulated form and with tolerance in value of deflection at different vertical loads upon which test had been done..
7.0 SHEAR LOAD vs DEFLECTION TEST: (Before Endurance test)
In this test the base plate of rubber bumper is rigidly clamped to a fixed horizontal plate and shear load is applied at the top of bumper to measure the shear load Vs shear displacement characteristics. The maximum lateral load shall be 150% of maximum shear load as specified in para 4.1 which shall be applied in both directions (Positive and Negative) from the mean position at a quasistatic frequency of 0.1 Hz . The pre-conditioning of bumper is done by giving three successive lateral load cycles and in the fourth cycle measurements are taken for applied shear load and corresponding shear displacement of bumper. The above test is conducted under gross vertical loads.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 22 of 33
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RDSO/Lucknow. Page 22 of 33
The measurements shall be done using digital methods and the measured data shall be provided in the form of hysterisis loop and tables (Ref. Annexure – II). The following geometric parameters shall be recorded as:
SNo. Parameters Before Endurance
Test After Endurance Test *
1 Free height (mm) 2 Outer dia (mm) 3 Vertical axis orientation
(mm)
* Ref. Para 10.0 Shear deflection in bumper should be given in tabulated form and with tolerance in value of deflection at different shear loads upon which test had been done.
8.0 ENDURANCE TEST:
a) The Endurance test is conducted to assess suitability of the rubber bumper for use in air spring provided at secondary stage suspension in coach bogie by simulating service conditions in the laboratory.
b) The test on bumpers shall be conducted only when the results of load deflection characteristics are obtained and found satisfactory.
c) The test shall be conducted in vertical and shear modes.
8.1 Vertical Endurance Test:
a) The bumper is subjected to a pre compressive load, which is equal to the gross load as specified in para 4.1 on an endurance testing machine. This load is taken as datum and further tests are conducted in load control mode.
b) With load datum as given in para (a) above, the plunger is made to oscillate vertically in sinusoidal manner at a frequency of 1.0Hz with 50 % of maximum gross load on the air spring such that the maximum compressive load on the plunger does not exceed 150% of the gross vertical load.
c) Endurance test shall be conducted for a total 1 million cycles at a stretch with conditions as stipulated in para (a) and (b) above.
d) During endurance test of 1 million cycle if the temperature build up in rubber bumper exceeds 7CC with respect to the ambient air temperature in the surroundings, the oscillating frequency of the plunger can be reduced by 0.5Hz.
e) At the end of every 0.2 million cycles following parameters are required to be measured (Ref. Annexure III)
a) Hystersis loop for 5 successive cycles of loads Vs deflections record (after every 0.2 million cycles of endurance testing )
b) Plunger oscillating frequency. c) Bumper temperature rise. d) Ambient/Room temperature. f) At the end of 1 million cycles following measurements/observations shall be recorded
after 30 minutes from load release.
S.No Parameters Results 1 Adhesion of bond. 2 Obvious signs of failures. 3 Excessive wear or Abrasions 4 Free height 5 Permanent set.
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 23 of 33
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8.2 Shear endurance test:
a) The base plate of bumper is clamped rigidly on a fixed horizontal table and subjected to a vertical pre compressive load which is equal to gross vertical load as specified in para 4.1 acting at the geometric centre of top plate. The test is conducted in load control mode and a horizontal force with sinusoidal frequency of 2.0Hz having peak load value as + 150% of maximum shear load as specified in para 4.1 is applied simultaneously for 1 million cycles.
b) During endurance test of 1 million cycle as per para (a) above, if the temperature build up in the rubber bumper exceeds 70
C with respect to the ambient air temperature in the surroundings the horizontal Oscillating frequency of the plunger can be reduced by 0.5 Hz.
c) At the end of every 0.2 million horizontal oscillating cycles of the actuator plunger following parameters are required to be measured. (Ref Annexure IV)
i) Hystersis loop for 5 successive cycle of horizontal load vs horizontal displacement record. After every 0.2 million Cycle of endurance test
ii) Actuator plunger frequency. iii) Bumper temperature rise. iv) Ambient/room temperature.
At the end of 1 million horizontal cycle, following measurement /observations shall be recorded after 30 minutes from vertical and lateral load release.
i) Adhesion of bonds. ii) Obvious sign of failures. iii) Excessive wear/ abrasion. iv) Free height. v) Tilt angle of vertical axis. vi) Permanent set.
9.0 VERTICAL LOAD vs DEFLECTION TEST.( after endurance test )
This Test is required to be conducted after satisfactory Endurance test and shall be carried out on the similar line as given in para 6.0.
10.0 SHEAR LOAD vs DEFLECTION TEST: ( after endurance test).
The test is required to be conducted after satisfactory shear Endurance Test and shall be carried out on the similar lines given in para 7.0.
11.0 SUPERIMPOSITION OF ACQUIRED DATA :
The following data obtained before and after Endurance Test shall be superimposed over each other as details given below :
11.1 Vertical Load Vs Deflection test data
The object is to determine the loss in vertical properties/characteristics of rubber due to endurance test. The characteristics test obtained vide para 6.0 and 9.0 shall be superimposed over each other in the form of hysterisis loop and comparative digital table (Ref. Annexure – V).
11.2 Shear load vs deflection test data
The object is to determine the loss in shear properties/characteristics of rubber due to shear endurance test. The characteristic data obtained vide para 7.0 and 10.0 shall be superimposed over each other of hysterisis loop and comparative digital table. (Ref Annexure VI)
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 24 of 33
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RDSO/Lucknow. Page 24 of 33
12.0 CREEP TEST
The Creep Test is conducted on an emergency rubber spring by applying a predetermined maximum vertical load, which is borne by the spring for a sufficiently long period to determine the magnitude of permanent set or loss in free height under the influence of load with respect to time. The predetermined maximum vertical load (150% of gross static load should be applied) continuously for a period not less than 5 days. The following measurements are required to be taken.
1. Magnitude of applied vertical load. 2. Free height of rubber spring (before and after creep test) 3. Height of rubber spring with respect to time. The height of the spring should be
measured after every 3 hrs for the first 2 days (48 hrs) and after every 6 hrs. thereafter.
The vertical deflection vs time curve should be drawn for the minimum period of 5 days. It can then be extrapolated depending on the expected working age of rubber spring (Ref. – Annexure VII).
13.0 GENERAL
a) All the tests mentioned in this specification shall be conducted on the same specimen of Emergency rubber spring.
b) All measurements shall be given in SI units. c) Lay out drawing of jigs and fixtures used in evaluating test parameters shall be
provided in the report. d) The test results shall be furnished by contractor in the form of a type test report. e) Digital photographs /pictures of test rig should be provided by the contractor. f) A list of instruments used in taking the measurements shall be supplied by the
contractor. g) Any other relevant details in support of accuracy of test shall be given in type test
report.
************
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 25 of 33
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RDSO/Lucknow. Page 25 of 33
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 26 of 33
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Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 27 of 33
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Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
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RDSO/Lucknow. Page 28 of 33
Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
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Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
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Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 31 of 33
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Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
Page 32 of 33
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Ref: CGW 0001,Rev.-3
Date / Month of issue: SEPTEMBER, 2008
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