description - vane pumps pumps/gear_pumps_general_informatio… · description : design &...

DESCRIPTION : DESIGN & CONSTRUCTION :

• Fixed volume, corrected involute spur gear design External • Gear pumps consists of a pair of gears supported by bushes, a

Gear Pump body, a flange and a cover.

LOW & MEDIUM PRESSURE APPLICATIONS : • Shaft of the driving gear projecting beyond the mounting

flange a twin-lip seal ring.• Mobile cranes

• Pump body mounting flange and port block are of high • Agricultural machinery strength cast iron.

• Mining machinery • Gears are made of steel(Case hardened) and are fine finished

to have a high degree of surface finish. • Forest machinery

• Proper tooth profile design and geometric proportions • Earth moving equipment ensure low pulsation levels.

• Lift trucks • An important feature of the pump is the deflecting pressure

balanced wear plates.• Construction equipment

• Low friction PTFE coated DU bushes are used to improve • Dump trucks, Tipping trucks& Dozers performance.

• Used in hydraulic log splitters Selecting the appropriate hydraulic pump for an application

is always a challenge because of different functional and • Fluid power transfer units (Power Packs) hydraulic system requirements, such as operating medium,

range of pressure, type of drive, etc. SALIENT FEATURES :

A gear pump is a mechanical device that moves liquids by the • 240 bar continuous operating pressure use of two meshing gears. Liquid flows under pressure from the

pump intake to the discharge in the space formed by the gear • Compact design teeth. The liquid also serves to lubricate the gears. The small

clearances between the walls of the pump chamber and gear • Good suction characteristics teeth create a tight seal, thereby preventing liquid from flowing

back through the intake. Unlike other types of pumps, gear • Easy to maintain pumps do not need to be primed and can be run dry for short

periods without damaging the pump.• Wide varieties of SAE , ISO & ANSI flange mounting options

are available Gear pumps are capable of producing high internal

pressures and they can pump very precise amounts of liquid at • Ports(Inlet & Pressure ports) - high pressures. Thick liquids such as crude oil can also be used in

• Side ported or Rear ported the pump.• Threaded ports

- BSP or UNF or Metric threads

• Flange ports(Metric or SAE)

- Metric or UNC threads

• Shaft Configurations

- Spline or Keyed (Refer to model wise ordering code)

• Bushings / roller bearing options available for long life &

lubrication

• Rotation

- Clockwise

- Counter Clockwise

- Bi directional

• Long seal life & high volumetric efficiency even at high

operating temperatures

Veljan Gear Pumps

Veljan Hydrair LimitedGear Pumps DivisionBalanagar, Hyderabad

Veljan Gear Pumps


Product Features :

DescriptionsFeatures

Pump Type

Displacement

Speed

Pressure (Inlet)

Pressure (Outlet)

Mounting

Ports

Shaft end

Drive

Inlet flow velocity

Hydraulic fluids

Fluid Viscosity(Mineral oils)

Fluid temperature

Direction of Rotation

Fluid Filteration

Multiple Pump assemblies

Separate or common inletcapability

Piggy back Assemblies

Heay-duty cast iron , 3 piece construction , External gear pump.

See Technical Characteristics


0.8 to 2 bar abs.13cm (5 in) Hg Maximum vacuum at operating temperature.


SAE , ISO Standard flanges , specials on request.

Threaded ports , SAE & Metric Split flanges

SAE Splined , Keyed , others on request.

Flexible coupling is recommended. Axial loading is not recommended.

Mineral oil and HFD • Inlet up to 2.5 m/s • Outlet up to 6.0 m/s • Outlet up to 4.0 m/s

Fire resistant fliuds HFB , HFC• Inlet up to 1.5 m/s

Mineral oils (Petroleum base) ,Bio degradable oil , Fire resistant fluids such as:water - oil emulsions 60/40 , HFB

• phosphate - easters, HFD (FPM seals required)• water - glycol , HFC

•

50 SSU minimum @ Operating temperature7500 SSU maximum @ starting temperatureViscosity range for cold start 1000 to 2000 mm²/s

Several models can be mounted together.VGP - C/B , VGP - D/B , VGP - E/C ,VGP - E/C/B

• • Two gear sets share common inlet.

Each gear section unit has inlet and outlet ports.

According to ISO 4406 code :19/16 at 140 bar (2000 psi)

• 17/14 at 210 bar (3000 psi)• 15/12 at 275 bar (4000 psi)

•

(For details see page no.8)

Clock wise , Counter clockwise. Viewed from the shaft end side.

Petroleum base oils with standard seals-20° C to +80°C (0 to 176°F).Temperature for cold start -20 to -15°c• Maximum permissible operating pressure is dependant on fluid temperature.

Fire resistant fluids HFB, HFC-20° C to + 65° C ( 0° to 150° F).

Operating temperature :

• Up to 3 gear sections of the same model,even with different gear widths.• VGP-BB , VGP- CC , VGP - DD , VGP - EE• Max. shaft load must be conform to limitations shown in the shaft load rating table in this catalogue• By adding the torque values for each pumping section (that will be simultaneously loaded) will determine the Max. load

Components in External Gear Pumps :

The non rotating parts namely Mounting flange, Housing & Port block are made of Cast iron.

Gear shafts :

Veljan Gear shafts are produced with precision manufacturing processes which will have a great effect on overall efficiency & performance of a pump. The manufacturing processes includes:

a) Case carburising & hardening in sealed quench furnace

b) Gear tooth profile are finish ground on latest Reishauer gear grinding M/C to maintain geometrical accuracies to DIN 5 quality.

Radial balance design in Gear engagement area :

Radial balance design must also take into account the fact that teeth in mesh cannot fully expel oil. As a result tiny fluid drops are 'squeezed' between the engaging teeth, thus entailing (depending on the incompressibility of the liquid) local over pressures that act in a radial manner. In addition, during gear disengagement, the volume between the teeth suddenly increases.

Consequently, the central part of bushings must have some slots in order to discharge this fluid; these are the only points where delivery and suction areas come into contact and the over-pressure prone fluid discharges in micro-areas subjected to early vacuum.

Thrust Plates & Seal assembly :

Each and every component in a Gear Pump plays an important role in its performance. The Axial & Radial compensations are made possible by placing two balancing or compensation bush bearings opposite the plane faces of the gears.

Bushing openings play another important role as they allow leakages to pass from the delivery area to the suction area where the leaked fluid mixes with fluid from the tank.

In axial and radial balance, the pressurized fluid, pushed through tiny and accurately measured openings between the outlet and the bushings, exerts a thrust on their two back parts. As a result, gears perfectly mesh bushings while the lubricating film prevents the faces of parts from wearing out.

The 3-shaped seal sets will balance the area and separates the suction area from the delivery area. It is supported by an anti-extrusion ring, with the same shape as the seal, so as to avoid the extrusion of the seal parts where it is not supported due to play.

Bush Bearings:

Bushings are positioned in the two covers (Port block & Mounting Flange) where gear shaft revolve; The problem is the accurate positioning of gear plane faces via cover surface plates. If they do not form a perfect right angle with tolerances less than 2-3 thousandths of millimeters, this would promote substantial leakages & early wear.

Roller Bearings :

Roller bearing pumps have these advantages:-• High strength • Long life for the roller bearings• Continuously pressure lubricated even when the pump is under no load• Can operate at high temperatures• Units are repairable due to roller bearing design• Roller bearing construction is relatively insensitive to moderate amounts of

contamination

Radial balance in the gear engagement area

Radial balance in the gear engagement area

Decompression

slots

Highly

Pressurized Fluid Vacuum

Drive gear

shaft Driven gear

Vacuum

Local Pressures

Decompression slots

Balancing / Thrust plates

Discharge

side

Axial gap - pressure compensated pressurized area

Suction

side

3- Shaped thrust plate seal Thrust Plate Back up ring

Slit

Veljan Gear Pumps


Technical characteristics:

Veljan Gear Pumps


PL Factor :Each section of a pump or motor should be regarded as a single unit with corresponding power unit requirements. The entire input horsepower is fed through the drive shaft, the power delivered or from the unit is limited by the strength of the shaft. The limit is defined as the "PL" factor. "P" being the operating pressure in psi and "L" is the sum of gear widths in inches.

In multiple units the "PL" must be calculated for each connecting shaft and must include the sum of the gear widths driven by it.

(Each shaft has a unique "PL" factor as can be seen in the table given below)Pressure(psi) x Total gear width (inches) = PL factor

VGP - B VGP - C VGP - D

9.8

14.9

19.9

24.8

29.8

34.9

39.9

2.6

3.9

5.2

6.5

7.9

9.2

10.5

15.9

24.0

32.0

40.1

48.1

56.3

64.4

4.2

6.3

8.4

10.6

12.7

14.9

17.0

20.6

31.0

41.5

52.0

62.4

69.8

83.4

89.9

104.2

5.4

8.2

8.2

10.9

16.5

18.4

22.0

23.7

27.5

240 240 240

3500 3500 3500

Specification

Displacement range

Max. speed

Max. flow

Flowat

1000rpm

Housing widths(in.)

0.88"

1.13"

1.38"

1.63"

1.88"

2.13"

2.38"

1.00"

1.25"

1.50"

1.75"

2.00"

2.25"

2.50"

2.75"

3.00"

Maximum pressure

Max. Pump Weight(approx.)

Units

cm³/rev

in³/revrpm

lpmgpm

lpm gpm

lpm gpm

(bar)

(psi)

(Kgs) 10.0 16.0 26.9

9.8 - 39.9

0.6 - 2.43

15.9 - 64.4

0.97 - 3.93

20.6 - 104.2

1.25 - 6.36

3000 3000 2400

39.9

10.5

64.4

17.0

104.2

27.58

VGP - E

43.8 - 146.5

2.65 - 8.85

2400

146.5

38.70

87.50

101.50

117.50

132.50

146.50

23.11

26.81

31.04

35.00

38.70

73.30 19.36

240

3500

31.8

58.98 15.58

43.80 11.57

Shaft Type Solid Shaft & Gear Loose Shaft

VGP-B

44503600134009900-

84506250130009300---

64504750990071001910013900-

----

5 550

6250625062506250625062506250

6450475099007100900090009000

VGP-C

VGP-D

Pl Factor Must Not Exceed Figure Shown In Chart For Shaft Type :

SAE "A" SplineSAE "A" KeySAE "B" SplineSAE "B" KeyConnecting Shaft

SAE "B" SplineSAE "B" KeySAE "B-B" SplineSAE "B-B" KeySAE "C" SplineSAE "C" KeyConnecting Shaft

SAE "B" SplineSAE "B" KeySAE "B-B" SplineSAE "B-B" KeySAE "C" SplineSAE "C" KeyConnecting Shaft

Application Guide Lines

Veljan Gear Pumps


Inlet Conditions:Recommended below should be followed at inlet condition of the pump:

• Never run pumps without oil - Particular care should be taken to open any shut-off valves.

• Use large diameter pipes and fittings and avoid sharp bends, elbows and long length lines.

• Pumps must be mounted below the lowest level of fluid tank as much as possible.

• Ensure that inlet lines are airtight.

• Be carefully in case there is high speed and/or high viscosity fluids are used in system.

• Fluid inlet velocity should not exceed 2.5m/sec (8.0 ft/sec ) calculated by:

V = (21.22*Q)/D² 3/sec where V= 0.0408Q/D² ft/sec where V = velocity (m/sec) V = velocity (ft/sec)Q = Flow range (l/min) Q = flow rate (US gal/min)D Bore diameter (mm) D = bore diameter (inches)

Cavitation:Hydraulic oil used in the modern hydraulic systems contains approximately 10% dissolved air by volume and this air implodes at certain pressure creating air pockets that can damage on metal surfaces. The main reasons are especially leakages in the suction port, unsuitable pipe sizes, elbow fittings and sudden changes in flow line.

Operating Temperature:Operating temperatures are the function of fluid visosities, fluid type, and the pump. For cold starts, the pumps should be operated at low speed and pressure until fluid warms up to an acceptable viscosity.• For NBR seals between 0°C and +80°C continuously and between -20°C and +100°C intermittent.• For VITON seals between 0°C and +100°C continuously and between -20°C and +120°C intermittent.

Inlet pressureUnder standard working conditions, intake pipe pressure is lower than the atmospheric pressure.The operating inlet pressure should range between 0.7 and 3 bars (absolute).

Hydraulic fluids:We recommend you to use only mineral oil-based hydraulic fluids having good anti-wear, anti-foaming (rapid de-aeration), antioxidant, anti-corrosion and lubricating properties. The fluids comply with the DIN/ISO or SAE standards Recommended viscosity range is 20/120(cSt) and permitted up to 700(cSt). If Hydraulic oil changes according to that the seals has to be changed.

For Mineral oil (Acc. ISO/ DIN) - NBR/FPM at temp.( -15 to + 83°C ) Fluid composition:- - HFB - NBR at temp.( +2 to + 65°C ) HFB - Water - in - oil emulsion 40/60- HFC - NBR at temp.( -15 to + 65°C ) HFC - Water - glycol 40/60- HFD - FPM at temp.( -10 to + 80°C ) HFD - Phosphate ester

Shaft alignment :

Splined :1. The permissible maximum misalignment is 0.06 mm (0.002 in) TIR for foot mounted pump and 0.03 mm (0.001 in) in case of flange

mounted pump. The angular misalignment between the shaft splines and the coupling internal splines should be less than +/- 0.002 mm per mm diameter of the pump shaft.

Keyed :1. These are supplied with matching Keys and in case replacement becomes necessary, use only high strength heat treated steel keys with

hardness of 27-34 Rc. The key corners must be chamfered properly so that it locates snugly in the keyway.

Veljan Gear Pumps


Filter Heat Exchanger

Return Line

Drive MotorTo Suction

Line

Dri

ve

Mo

tor

To SuctionLine

Drive

Mo

tor

Shaft In Vertical

Axis

Shaft In Horizontal Axis

Suction tube endshould be cut off at an angle of 45° or shaped like an open funnel.

ON/OFF

Ød

h <

10

x Ø

d 8 x

d

Baffel

Fulid Line

Breather

• Pipe internal diameter must be more than the pump suction flange bore.

• The pipe/tube end of the suction line shall be machined at 45° or provided a funnel like outlet.

• Pipe bending shall be done to maximum possible radius.

• Suction line closer to the pump shall be out of a flexible hose.

ParticlesSizeRange

MaximumParticles

5-15µm

15-25µm

25-50µm

50-100µm

>5µm

>15µm

>100µm

7

32,000

5,700

180

32

1,012

38,924

6,924

6

16,000

2,850

90

16

506

19,462

3,462

5

8,000

1,425

45

8

253

9,731

1,731

4

4,000

712

22

4

126

4,864

864

3

2,000

356

11

2

63

2,432

432

2

1,000

178

6

1

32

1,217

217

1

500

89

3

1

16

609

109

00

125

22

1

0

4

152

27

0

250

44

2

0

3

304

54

CLASS

8 9 10 11 12

64,000

11,400

360

64

2,025

128,000

22,800

720

128

4,050

256,000

45,600

1,440

256

8,100

512,000

91,200

2,880

512

16,200

1,024,000

182,400

5,760

1,024

32,400

77,849 155,698 311,396 622,792 1,245,584

13,849 27,698 55,396 110,792 221,584

>5µm

>15µm

ISO solid contamination code

8/5 9/6 10/7 11/8 12/9 13/10 14/11 15/12 16/13 17/14 18/15 19/16 20/17 21/18

250

32

500

64

1000

130 250 500 1000 2000 4000 8000 16,000 32,000 64,000 130,000

22/19

2000 4000 8000 16000 32000 64000 130,000 250,000 500,000 1,000,000 2,000,000 4,000,000

250,000 500,000MaximumParticles

ISO:DIS 4406; SAE J1165:-

These pump facts are certainly useful when discussing the impact of ISO cleanliness on working hydraulic or circulating system components.

National Aerospace Standard (NAS) 1638 :

Hydraulic fluid- Recommended Seal standards :

Fluid Standard

DescriptionSeal Standard

S - 1 S - 4 S - 5

HF - 0 R N A

R

R

R

N A

N A

N A

HF - 1 / HF - 1A

HF - 2 / HF - 2A

HF - 3

HF - 4 R N A

HF - 5

N

N

N

R

R

R

N

N

N

N

N

N

N

A

A

A

A

R

R

R

R

N

N

N

N

R

R

R

R

N

N

N

N

Premium Hydraulic Oil

Petroleum Base Oils

Petroleum Base Oils with Anti-wear

Invert Emulsions

Water Glycol

Synthetic fluids: (Phosphate Esters)

Skydrol 500B, 500C, 7000, LD

Pydraul 60, 10F

Pyrogard 53

Fyrquel 150, 300

Houghtosafe 1010, 1055, 1120

Pyrogard 55, 190, 600

Pydraul series E (except 10E)

Fyrquel 220

Coolanol 25, 35, 45

Pyrogard 42, 43, 160, 230, 630

Pydraul (all except 60 & series E)

MIL-L-23699

Oronite 8200, 8515, M2-V

OS45 (Type 3rd & 4th), OS49

Versilube F- 44, F- 50

N

N

N

N

R

R

R

R

N

N

N

N

Legend : R = Recommended N = Not suitable A = Alternate S-1 : Buna-N S-4 : EPR S-5 : Viton

Veljan Gear Pumps


Hydraulic Formulae

WORD FORMULA LETTER FORMULAFORMULA FOR

2FLUID PRESSURE, P (lbs/in )

2CYLINDER AREA (in )

FORCE (PUSH OR PULL) (lbs)

VOLUME, V (gallons)

FLOW, Q (gpm)

VOLUMETRIC EFFICIENCY

(PUMP)

ŋv

OVERALL EFFICIENCY, ŋo

2AREA x diameter = π

4

2FORCE = Pressure (psi) x AREA (in )

231 x Flow Rate (gpm)VELOCITY = -------------------------------------------- 12 x 60 x Area (sq. inches)

Force (lbs)PRESSURE = ----------------------

2 Area (in )

2 π x Radius (inches) x Stroke (inches)VOLUME = ------------------------------------------------------------- 12 x 60 x Area (sq. inches)

Displacement (in³/rev) x speed (rpm)FLOW = ---------------------------------------------------------------------------- 231

Output (gpm)Vol. Eff = -------------------------------- x 100 Theoritical (gpm)

Output HPOve. Eff = ----------------------- x 100 Input HP

FP = ----- A

2 πDA = -------- 4

F = P.A

Q.PHP = -------------- 1714 ŋo

231 Q = --------------

720 Au

2 πr LV = -------------- 231

d. nQ = ----------- 231

MOTOR TORQUE (lb inch)

MOTOR TORQUE, T/100 psi

MOTOR SPEED, n (rpm)

MOTOR POWER, HP

VOLUMETRIC EFFICIENCY,

(MOTOR)

ŋv

63025 x Horse PowerTorque = -------------------------------------- Speed (rpm)

36.77 x Flow Rate (gpm) x Pressure (psi)= --------------------------------------------------------------------- Speed (rpm)

Motor Displacement (in³/rev.)TORQUE/ 100 psi = ----------------------------------------------------- 0.0628

231 x Flow Rate (gpm)SPEED = ---------------------------------------------------- Motor Displacement (in³/rev.)

Torque Output (inch pounds) x Speed (rpm)HORSE POWER = --------------------------------------------------------------------------- 63025

Theoritical (gpm)Vol. Eff = ----------------------------- x 100 Input (gpm)

63025 HPT = ------------------------ n

36.77 QPT = ------------------------ n

dT/100 psi = -------------- 0.0628

231 Qn = -------------- d

T.nHP = -------------- 63025

2Pipe volume varies as the square of the diameter; volume in gallons = 0.0034 D L

where D = inside diameter of pipe in inches

L = Length in inches

0.320 x flow (gpm)

Velocity in feet per second = ---------------------------------------

D

Specific gravity of oil is approximately 0.850Thermal expansion of oil is about 1 cu. in. per 1 gallon per 10 F rise in temperature

Conversion Factors :

1 HP = 0.746 kw hr 1 bar = 14.5053 psi 1 kg = 2.2045 lbs

1 US gallon = 231 cubic inches. 1 kg = 9.8066 N

1 gallon/min = 3.8 lpm

VELOCITY or SPEED (ft./sec)

Flow (gpm) x Pressure (psi)HORSEPOWER = ------------------------------------------------- 1714 x Overall Efficiency

PUMP INPUT POWER (HP)

Veljan Gear Pumps


Veljan Gear Pumps


Principle of Operation :

The working principle of the external gear pump.

A drive gear (that is driven by a motor) rotates an idler gear in the opposite direction. When the gears rotate, the liquid, which is trapped in the gear teeth spaces between the housing bore and the outside of the gears, is transferred from the inlet side of the pump to the outlet side. It is important to note that the pumped liquid moves around the gears and liquid moves around the gears and not between the gears. The rotating gears continue to deliver a fresh supply of liquid from the suction (inlet) side of the pump to the discharge (outlet) side of the pump, with virtually no pulsations. The meshing of the gears on the discharge side of the pump forces the liquid out of the pump and into the discharge piping.

Another important advantage of the gear pump is its self-priming capability. Gear pumps are capable of self-priming because the rotating gears evacuate air in the suction line. This produces a partial vacuum that allows the atmospheric pressure to force the liquid into the inlet side of the pump. This ability of the gear pump makes it an ideal choice when the application requires that the pump be located above the liquid level, pump be located above the liquid level, and the liquid must be lifted to the pump. Because a gear pump cannot create a perfect vacuum, the total lift (including pipe friction losses) should not exceed about 7.5 PSI, or about one-half of the atmospheric pressure.

Long shaft journals (hydrodynamic bearing) provide superior bearing surface and premium material selection as well as the minimum number of rotating parts, contribute long efficient service life of VELJAN GEAR PUMPS.

INL

ET

OU

TL

ET

Mounting flangeHousing

Drive shaft

Port block

3

12 14 15

13

5 6

4 6 5 5 1011

10

10 11 106 5 4 3

2

20 3

19 18 17

1

9

3 4 5 6 8

7

2

Veljan Gear Pumps


Tandem Pump Exploded View

Item ItemItemItemPart Description Part DescriptionPart DescriptionPart DescriptionQty QtyQtyQty

01

02

03

04

05 Thrust plate seal

Thrust plate Back up ring

DU-Bush

Locating bush

Mounting Flange 01

16

08

04

04

06

07

08

09

10

Driven gear

04

01

03

01

04

11

12

13

14

15

Housing

Port block

Washer

Stud

Hex.nut

02

01

04

04

04

16

17

18

19

20

Bearing carrier

Shaft seal

Deep groove ball Bearing

Internal Circlip

Connector

01

01

01

01

01

16

Thrust Plate

Drive Gear Shaft

Plug

O-Ring

Identification and Trouble Shoots in Hydraulic Installations:-The following tabulations should be of assistance in the location and modification-repair of sources of trouble.Any contamination reduces the life-time of hydraulic installation.

1 - Pump does not deliver2 - Pump / motor make loud noise3 - Pump / motor overheats4 - Pump develops low pressure

5 - Motor does not work6 - Shaft clearance too great7 - Leakage at pump or motor

Source of TroubleEffects

Modification - repair1 2 3 4 5 6 7

Veljan Gear Pumps


Wrong detection of rotation

Oil level too low

Dirty filter

Faulty suction valve

Air in system

Suction pipe leaks

Pump shaft broken

Wrong oil grade

Oil too cold

Suction height too great

Pump speed too high

Dirty vent or no vent reservoir

Cavitation

Suction pipe leaks

Shaft seal leaks

Filter too small or is dirty

Suction pipe bore too small

Casing leaks

Pump or motor part defective

Pump or motor stressed

Foreign bodies in suction side

Pipe bends in suction side

Oil temperature too high

Boost pump failed

Resonance through tank

Porous suction hose

Vibration in system

Other defect of pump or motor

Oil speed in system too high

Radial or axial loading too high

Initial speed rises

Inadequate cooling

Cooling system is dirty

Differential pressure too low

Pressure too high

Wrong type pressure valve

Faulty operation in system

Wrong seals

Pump running speed high

System contaminated

Other defects of the pump

Wrong pressure setting

Pressure valve sticks

Leakage in system

Faulty electric circuit

Drive machine defective

Wrong gaskets and seals

Switched to pressure less return

Torque too low

Oil spill at motor

Inadequate pump delivery

Too much play in the shaft

Defective bearing

Radial or axial loading too high

Coupling out of balance

Connection leaking

Casting leaks

Damage to plane faces

No safety valve in motor circuit

Reverse motor poles or reverse rotation of pump

Top up with oil

Clean filter or replace element

Repair or change the valve

Vent system

Replace jointing or seal

Establish cause(pump over loaded?) and replace shaft

Respect oil recommendations (For special fluids take VELJAN advice)

Let pump warm up at low pressure, or install a heating system

Reduce suction height or install boost pump, or pressurize the tank

Reduce running speed

Clean or install vent

Vent system and seal

Replace joint or seal

Replace shaft seal

Install larger filter or clean filter

Fit pipe of larger nominal size

First tighten bolts, then check for cracks and sealing

Replace defective parts

Check mounting alignment tighten bolts uniformity

Remove foreign bodies, if needed flush system

Eliminate or at least reduce the bends

Check circuit for cause(cooling?)

Establish cause and repair defect

Change deposition of tanker install sound damping means

Change disposition of tanker install sound damping means

Establish source and repair defect

Disassemble pump/motor,check parts,test run on test-bench

Install pipes of greater nominal size

Limit to acceptable amount, check alignment

Check max. pressure; if needed increase pump size

Increase cooling capacity

Establish cause and repair defect

Increase pressure setting or feed pressure

Reduce pressure setting

Replace by appropriate type of valve

Check circuit and modify system

Replace by suitable seals

Reduce speed

Flush system or if needed pickle and flush out

Disassemble pump or motor, check parts or run on test bench

Modify pressure setting and increase pressure

Repair defect

Seal system - replace defective parts

Check electric circuit

Repair machine

Replace by seals prescribed

Modify switching

Increase pressure setting

Check ball valve. Check if stroke defective

Repair pump or change for larger type

Replace bearing

Exchange bearing

Limit to permitted amount

Balance or replace coupling

Check seals

Check for cracks and if necessary replace

Machine plane faces flat

Install a safety valve

Service Instruction for “Bush Bearing Pumps” :

1

23

4

5

6

7

8

6

5

4

10

11

9

2

10

3

1213 14

15 16

17

Item Qty

01 01

02 01

03 01

04

01

05

01

06 02

07

02

08

02

09

10

08 11

01

12

01

13

14

01

15

04

16

04

17

04

Part Description

Mounting Flange

Drive gear shaft

Driven gear

Thrust plate

Thrust plate seal

Thrust plate Back up ring

Locating bush

Plug

DU-Bush

02

01

Item

Housing

Port block

Shaft seal

Internal Circlip

Washer, M16 Hex.Bolts-M16x130lg

O-Ring

Deep groove ball Bearing

Part Description Qty

Veljan Gear Pumps


Cautions: Disassembly Instructions :

During assembly, use extreme caution when prying apart castings. The 1) Clamp the pump in a vise, with the drive shaft pointing down, on the marring of machined surfaces could cause leakage. Excessive use of force mounting flange.can result in misalignment and seriously damage parts.

2) Scribe a line across each casting in the assembly. This ensures proper Installation Instruction : alignment during reassembly.

1. Check the direction of rotation as per the arrow mark indicated on 3) If the pump has a key type shaft, remove the key from the drive gear. the pump body. Lightly stone any burrs that may be on the shaft to prevent any

damage to the seal during disassembly.2. Check Inlet conditions of the pump. Intake conditions for all pumps

should be suitable for easy flow of oil. 4) Remove all the bolts & washers from the assembly.

As far as possible, try to avoid bends and use large size pipes as 5) Remove the rear port end cover.recommended.

6) Remove the thrust plate by hand. The channel seals can remain in the3. Ensure proper coupling connection to the driven shaft to minimize thrust plate groove.

pump shaft load.7) Carefully remove the gears from the gear housing. Keep gears

4. Check the shaft suitability for supporting operating torque. together because they are a matched set

5. Check the filter suitability for lowest contamination level. 8) Carefully remove the thrust plate by hand from the shaft end cover surface. Keep the channel seals in the thrust plate groove.

Start-up Procedure :9) Lift the gear housing from the shaft end cover. Keep the gasket seals in

• Back off the main relief valve until the spring tension on the adjusting the gear housing groove.screw is relieved to avoid the immediate damage to the pump.

• Check all the ports filled with clean oil to provide initial lubrication in the case of the unit is located above the oil reservoir.

• Run the pump at least 2min. at no load and at low rpm. During this break-in period, the unit should run free & not develop an excessive amount of heat. If the unit operates properly speed & pressure can then be increased to normal operating settings.

• Reset the main relief valve to its proper setting.

Veljan Gear Pumps


Service Instructions:

Anticlock Wise Rotation

These instructions are intended for use in changing the rotation of a single section VGP series gear pump.

Reassembly Instructions:

1) If unit has two holes in the face of the shaft end cover, move the plug to the open hole that was marked. Inlet side will be open, outlet side will be plugged. Apply lock tight to threads and stake plug in hole.

2) Rotate Gear housing 180° from original position and place over shaft end cover. Make sure gasket seals are in the grooves, a light coat of grease will hold them in.

3) It may be necessary to reposition the locating bushes.

4) Gently slip the thrust plate into the gear housing bore with the channel seals towards the shaft end cover. The relief groove in the plate must face the outlet side of the pump.

5) Slide the drive shaft gear through the gear housing, bushing and shaft seal. Be careful not to damage the shaft seal.

6) Slip the second thrust plate over the gear journals and into the gear housing. The channel seals will be facing up. The relief groove in the plate must face the outlet side of the pump.

7) From its original position rotate the port end cover 180° around the shaft axis & position over the gear housing. Lightly tap the port end cover down until it rests against the gear housing.

8) Replace the washers and bolts into the unit. Torque bolts in a cross corner pattern.

9) Rotate drive shaft with a small wrench to check for any binding.

PlugInlet

Clock Wise Rotation

PlugInlet

Veljan Gear Pumps


Service Instructions:

Seal replacement Instructions

Important: Note the shape and orientation of all seals before and during removal.

The first requirement for good maintenance of hydraulic Pump or equipment is cleanliness. extreme cleanliness is most important in hydraulic system.

MAKE SURE THE MAINTENANCE OF YOUR HYDRAULIC EQUIPMENT IN A CLEAN AREA

Shaft seal:

1) If shaft end cover has circlip (or) smalley ring and outboard bearing, carefully remove. Insert small diameter punch from inside cover into shaft seal opening. Gently tap to drive out the lip seal.

2) Apply a light coat of non-hardening gasket sealant in the outer edge of the replacement seal. Press the seal flush with the seal recess in the shaft end cover.

Gear Housing Gasket Seals:

1) Carefully remove seals in groove.

2) Insert new seals in grooves. Apply a light coat of grease to seals to hold it in place during reassembly of pump.

Thrust plate Seals:

1) Remove the back-up seal and channel seal from groove in back of thrust plate.

2) Place the soft black Buna-N seal into the seal groove with the flat side down. Place the hard white nylon back-up seal, flat side up, into the groove on top of the Buna-N seal.

Shaft , Couplings and Female Splines :

1. The coupling spline must be lubricated with a lithium molydi - sulfide grease or a similar lubricant.

2. The mating female spline should be free to float and find its own center. The members are rigidly supported, they must be aligned within 0.15 mm TIR or less ,to reduce fretting. The angular alignment of two splines axes must be less than ±0.05 mm per 25.4 mm radius.

3. The coupling must be hardened to a hardness between 27 and 45 RC.

4. The female spline must be conform to the class 1 fit as described in SAE - J498b.This is described as Flat root side fit.

5. Flexible coupling alignment is preferred and the usage of these couplings should be as per the recommendations of manufacturers.

External shaft loads are not allowed

1. External Radial and axial shafts loads are not allowed on the pump shaft.

2. Bearing supported coupling must be used in case of (to avoid) radial and axial shaft loads on external.

3. The pumps are designed for in-line-drive only and no side loading on the shaft is permissible beyond the specific limits.

Radial loads not allowed

Axial loads not allowed

PortSize

BSPP

Port ID, A (mm) Thread(BSPP)

1/8"

1/4"

3/8"

1/2"

3/4"

1"

1 1/4"

1 1/2"

2"

8.60 (0.34)

11.50 (0.45

14.92 (0.59)

18.52 (0.73)

24.10 (0.95)

30.20 (1.19)

38.67 (1.53)

44.75 (1.77)

56.52 (2.23)

1/8" - 28

1/4" - 19

3/8" - 19

1/2" - 14

3/4" - 14

1" - 11

1 1/4" - 11

1 1/2" - 11

2" - 11

SAEFlange size in.

A B Thread (C)

mm in.

38.10 1.5

47.63

52.37

1.88

2.06

58.72 2.31

mm in.

17.48 0.69

22.23

26.19

0.88

1.03

1.1930.18

69.85

77.77

2.75

3.06

88.90 3.50

35.71

42.88

1.41

1.69

2.0050.80

106.38 4.19 2.4461.93

UNC

5/16"-18

3/8"-16

3/8"-16

7/16"-14

1/2"-13

1/2"-13

1/2"-13

5/8"-11

1/2"

3/4"

1"

1 1/4"

1 1/2"

2"

2 1/2"

3"

Metric

M8

M10

M10

M10

M12

M12

M12

M16

Dmm

24

22

22

28

27

27

30

30

Veljan Gear Pumps


6.85 (0.27)

10.00 (0.39)

13.00 (0.51)

17.60 (0.69)

20.50 (0.81)

25.00 (0.98)

31.30 (1.23)

39.20 (1.54)

45.60 (1.79)

61.50 (2.42)

PortSize

UNF (ODT)

Port ID, A (mm) Thread(UNF)

1/8"

1/4"

3/8"

1/2"

5/8"

3/4"

1"

1 1/4"

1 1/2"

2"

5/16" - 24

7/16" - 20

9/16" - 18

3/4" - 16

7/8" - 14

1 1/16" - 12

1 5/16" - 12

1 5/8" - 12

1 7/8" - 12

2 1/2" - 12

Spot Facedia, B (mm)

17.06

21.03

24.61

30.17

34.13

41.27

48.51

57.66

65.02

88.39

Min. Depth, C

(mm)

16.66

19.43

21.41

23.79

26.18

31.75

31.75

31.75

31.75

36.52

A

A

B

ØC

B

C

D

A

British Standard Pipe Parallel (BSPP)

Port Details:-

SAE Straight threaded ports (ODT)

Veljan Gear Pumps


Tandem pump

VGP - E,D,C Series

VGP - D,B SeriesSTEP DOWNVGP :- E - DVGP :- D - BVGP :- C - B

VGP - E-E SeriesVGP - D-D SeriesVGP - C-C SeriesVGP - B-B Series

VGP - D,C,BSeries

ADD ON - VGP E - 2 bolt A VGP E - 2 bolt B VGP D - 2 bolt A VGP D - 2 bolt B

description - vane pumps pumps/gear_pumps_general_informatio… · description : design &...

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