bulroc dth
Post on 23-Oct-2015
179 Views
Preview:
DESCRIPTION
TRANSCRIPT
MAINTENANCE OF HYPER HAMMERS
2
3
4
5
6-7
8
9-10
11
12
2
The BULROC Hyper 241 down the hole hammers is a strong and robust tools of a simple and straight forward design to provide maximum performance within a minimum of maintenance.
Please Note:That, contrary to some other BULROC hammer models, the Hyper 241 does use bits with Footvalves.
The BULROC Hyper 241 is supplied as standard with a Check Valve arrangement which is designed to maintain the pressure inside the hammer when the air is switched off and so help prevent contaminated water from entering the hammer.
The BULROC Hyper 241 is designed to give optimum performance with the minimum consumption of compressed air. If, however, particular deep-hole application require extra air flushing. This can be achieved by drilling through the soft alloy plug in the piston. More information is given on page 5.
List of Contents
1. Introduction
13STORAGE PROCEDURES AND TROUBLESHOOTING
PISTON
BACKHEADADAPTOR
HYPER 241 HAMMER
ADAPTORBREAKOUT WASHER
ADAPTOR wASHER
CHECKVALVE
CHECKVALVESPRING
DIVERTER
COMPRESSIONBUFFER
CONTROL TUBEBUFFER
CONTROL TUBE
BACKHEAD
BACKHEAD ‘O’RING
BACKHEAD SEALING‘O’RING
CONTROLTUBE ‘O’RING
BREAKOUTWASHER
WEARSLEEVE
BITRETAINER
BREAKOUTWASHER
CHUCK‘O’RING
CHUCK
BIT
2.
Ref Description Part No.
1 Backhead Adapter HSH24138AD082M
2 Adapter Breakout Washer HSH24127
3 Check valve HSH24108
3a Check valve Spring HSH24110
4 Adapter Washer HSH24106
5 Breakout Washer HSH24126
6 Backhead ‘O’ Ring HSH24114
7 Diverter HSH24107
8 Compression Buffer HSH24123
9 Backhead HSH24138
10 Backhead Sealing ‘O’ ring HSHBS464
11 Control tube buffers HSH24129
12 Control tube ‘O’ ring HSH241514
13 Control tube HSH24130
14 Piston HSH24103240
15 Wearsleeve HSH24100
16 Bit retainer ‘O’ ring HSHBS461
17 Bit retainer HSH24137241
18 Chuck ‘O’ Ring HSHBS464
19 Breakout Washer HSH24126
20 Bit Bearing HSH24135241
21 Chuck HSH24135240
3. Hammer Parts List
HYPER241
STANDARD BACKHEADCONNECTIONS
85/8”
Reg Box
STANDARD CHUCKCONNECTION
NUMA240
LENGTH(WITHOUT BIT)
92.70”2355mm
LENGTH(BIT EXTENDED)
105.75”2686mm
LENGTH(BIT RETRACTED)
103.25”2623mm
OUTSIDE DIAMETER OF HAMMER
23”584mm
BORE DIAMETER17”
432mm
PISTON STROKE6”
152mm
PISTON WEIGHT1400lbs630Kg
COMPLETE HAMMER WEIGHTWITHOUT BIT
5522lbs2510Kg
4. Hammer Specifications
Working Pressure
5. Air Consumption
6.89 100
13.78 200
20.68 300
BARPSI
1000 - 28.3
2000 -56.23
3000 - 84.94
4000 - 112.46
CFM CMM5000 - 141.5
Extra flushing air for a choke in cubic feet per min
100 psi68
152270422607
125 psi83
286330507731
150 psi98
220390593855
175 psi113253450694
1001
Hole Size6mm
10mm13mm16mm19mm
Extra flushing air for a choke in cubic metre per min
100 psi1.924.307.6411.9417.18
125 psi2.305.269.34
14.3720.69
150 psi2.776.2311.0416.7924.21
175 psi3.207.18
12.7519.6628.34
Hole Size6mm
10mm13mm16mm19mm
Total air requirements for chokes in cubic feet per min
100 psi218822562340245926102796
125 psi305931423245338835663790
150 psi402141194241441146144876
175 psi506751805320551757616067
Hole Sizeblank6mm
10mm13mm16mm19mm
Total air requirements for chokes in cubic metre per min
100 psi61.9763.9066.2869.6273.9279.16
125 psi86.6188.9691.8895.96
100.98107.31
150 psi113.85116.63120.08124.90130.65138.07
175 psi143.48146.67150.65156.22163.14171.82
Hole Sizeblank6mm
10mm13mm16mm19mm
Drill through this faceshould extra flushingbe required see below
Additional Flushing
The Hyper 241 has a control tube with a softened face which can be easily drilled through to allow foe extra flushing air should this be required.In certain drilling conditions extra flushing air may be required to overcome increasing back pressure and maintain the necessary up hole velocity to ensure efficient hole cleaning. In such conditions, a small hole can be drilled into the face of the control tube which will allow extra live air to be delivered directly to the bit face. The size of the hole will determine the extra volume of air delivered to the bit face depending on the operating pressure.
The top two tables show the extra flushing air which can be expected with the chokes drilled.
The lower two tables shows the total air required for optimum hammer performance with the chokes drilled.
The Hyper 241 is produced with a raised band on the O.D. of the wearsleeve. This band incorporates 4 holes for a custom made 'cee' spanner to assist splitting.The backhead, backhead adaptor and chuck all have spanner flats incorporated to house a custom made spanner.
(Nb. On no account should the wearsleeve be impacted by a hand hammer or splitting be assisted by the use of localised heat i.e. blow torch.)
Assuming the hammer is new stripping can be achieved as is. However should the hammer be subjected to normal working conditions the torque applied will hinder stripping. The Hyper 241 has at all threaded connections a 6mm breakout washer of a soft steel makeup. This can be easily dug out on site using a hand grinder. Care must be taken not to damage any of the parent parts of the hammer. This will have the effect of releasing the applied torque and will make stripping easier.Apply liberal quantities of penetrating oil at all thread joints.
.1. With the hammer in a horizontal position the chuck assembly can be removed. This incorporates the bit, chuck and bit retainer.
2. Still in the horizontal position the backhead assembly can be removed in the same way. This incorporates the control tube and check valve assembly.
3. With the backhead end of the wearsleeve in an elevated position, the piston should slide out fairly easily.
6. Stripping the hammer
1. Remove the 'O' rings around the bit retainer, allowing the bit retainers to be removed.
2.. The bit can now be easily removed from the chuck.
1. Remove the Adapter from the backhead. This will expose the internals of the backhead.
2. The Check Valve assembly can now be removed. A slight tapping on the control tube will assist this.
3. The control tube assembly can now be removed.
7. Stripping The Chuck Assembly
Stripping the Backhead assembly
Premature wear to internal parts is a result of either:-
Piston1. Incorrect or insufficient lubrication.2. The ingress of debris into the hammer.3. Incorrect service and storage.
The maximum wear allowances shown in this section are a guide as to whento replace parts. In certain conditions parts may need to be replaced beforethey reach the sizes shown.
1. There are two main areas to examine on a used Piston. Check the Body diameter 'A' for signs of 'Pick-up' and burning (both are signs of poor lubrication.) Using a micrometer, measure the diameter and refer to the table for the minimum size.Any light 'Pick-up' marks can be removed by using emery cloth, however if there are signs of overheating and cracking, the Piston should be replaced and the lubrication system examined.
The minimum diameter recommended on the piston is 17.005”
Secondly, examine the Striking Face. Distortion is acceptable providing there are no signs of cracking. Burrs and dents can be removed with an emery stone.
Control TubeExamine the Control Tube Dia. 'A', using a micrometer, check the diameter has not worn under the specified minimum. If there are signs of 'Pick-up' they should be removed by using emery cloth.
The minimum diameter recommended on control tube is 7.988”
Wearsleeve Using either a micrometer or a vernier, measure the outer diameter 'A' of the Wearsleeve. If it is below the minimum it must be replaced. The wear rate of the Wearsleeve can be slowed by replacing the Chuck before the wear area reaches the Wearsleeve.The bore of the Wearsleeve should be periodically checked for any signs of 'Pick-up'.The minimum recommended diameter for the wearsleeve is 22.600”.
If a Piston has broken within the Wearsleeve it is imperative that the bore is honed to remove any Burrs or 'Pick-up'. Failure to do so will result in 'Pick-up' on the replaced Piston and will lead to early failure of this component.
8. Checking for Wear and Damage
1. With the wearsleeve raised at the backhead end slightly insert the piston with the striking face forward. The piston should fall until it reaches a physical stop.2. Re-assemble the backhead assembly taking note to add a new breakout washer between the backhead and backhead adaptor Tighten using the spanner flats, on drilling the thread will tighten to their working torques.3. Assemble the chuck assembly ensuring the 'O' rings are placed over the bit retainers, which will keep the assembly together until inserted in the wear sleeve.4. Screw both the Backhead and Chuck Assemblies into the wearsleeve again finger tight as the drilling wil tighten the threads.
As a preventative maintenance measure, it is suggested that all 'O' rings be checked at this stage be examined for cuts, burrs etc and if need replaced
.
Three can be found on the Hyper 241 backhead
And one can be found on the chuck
The Chuck Bearing should also be checked for damage and if necessary replaced
Due to the weights involved it is recommended that the hammer be assembled in a horizontal position with the wearsleeve raised above ground level sufficient for the bit to clear the ground.
9. Assembling the Hammer
Backhead
Checkvalve Assemby
CompressionBuffer
Control TubeAssembly
Piston
ChuckAssembly
1. Ensure all the maintenance work outlined in the previous section has been completed.
2. Lay the Wearsleeve on two wooden blocks, support the chuck end so as to raise the sleeve 50mm - 70mm off the ground this will make it easier to screw in the chuck assembly.
3. Assemble the Chuck, Chuck Release Washer and Bit Retainers around the Bit ensuring the Chuck and Bit Retainers are fitted with new ‘O’ Rings. Check the condition of the Drive Plates (or pins) and the Chuck Bearing and replace if necessary. Cover the threads with a Copper based grease. Then screw the Chuck fully in until there is no gap between the Wearsleeve and the Chuck Release Washer.
4. Coat the Piston with rock drill oil and slide it into the Backhead end of the Wearsleeve. (Ensure the Piston striking face enters first).
5. Assemble the two Control Tube Buffers and the ‘O’ Ring around the Control Tube, then push the assembly into the Tube Holder. Coat the outside of the assembly with rock drill oil and insert it into the Backhead end of the Wearsleeve
6. Slide the Compression Ring on to the Control Tube Assembly.
7. Insert the Spring into the Check Valve and then slide the assembly into the Valve Chest. Fit the Buffer Cover to the Valve Chest. Push the whole assembly down onto the Compression ring.
8. Fit a new ‘O’ Ring to the Backhead and coat the threads in Copper based grease. Fit the Backhead Breakout Washer. Screw the Backhead into the Wearsleeve until it is hand tight, then measure the gap between the Wearsleeve face and the lock-up face on the Backhead. This gap should be a minimum of 2mm, - if the gap is smaller the ring should be removed and replaced with a new Compression ring. When the gap exceeds 2mm the Backhead should be fully tightened using the appropriate Backhead Spanner.
10. Rebuilding the Hammer
11 BUTTON BIT FOOT VALVES 11 BUTTON BIT FOOT VALVES
Bulroc Hyper hammers are designed to be used with Foot Valves that are to the following specifications:
LUBRICATION LUBRICATION
To guarantee the diameter and protrusion height are correct it isrecommended the correct insertion tool is used.
Using Foot Valves which are larger in diameter than the sizesshown, will result in premature failure of the Foot Valve.
Foot Valves which are much smaller in diameter than thesizes shown will reduce the performance of the hammer.
PR
OT
RU
SIO
N H
EIG
HT
‘A’
FOOT VALVEØ’B’
INS
ER
TIO
N T
OO
L
11. Button Bit Footvalves
Protrusion height (A) 75mm (2.95)Foot Valve Diameter (B) 113.3mm (4.45”)Shank Type N240
12. Lubrication
The Hyper 241 piston oscillates at 600 bpm at 150 psi (10bar). It is therefore extremely important that an adequate supply of the correct type of rock drill oil is constantly fed to the hammer whilst it is operating.Failure to do so will quickly lead to excessive component wear and if the oil supply is cut of for any reason, the piston will quickly seize inside the wearsleeve, resulting in irreparable damage to both components.An air line lubrication system should be installed, preferably on the drill rig. The lubricator reservoir should be of sufficient capacity to supply the required volume of rock drill oil for a full shift. With larger hammers, this may be impractical but the capacity should be sufficient for at least half a shift. This is equally important that the lubricator system must be adjustable and have a visual check to ensure the lubricator does not run out of oil.As a good general guide, all Bulroc Hyper hammers require a third of a pint of oi per hour, per 100cfm of air through the hammer ( 0.07 litre per metre cubed)
Eg Hyper 241 operating at 150psi = 4020 cfm = 13.6 pints per hour10.3bar = 114 = 7.2 litre per hour
The amount of lubricating oil should be increased by 50% when drilling with water or foam.When new drill pipes are added to the drill string, it is recommended that a half pint ( a quarter of a litre) of rock drill oil is poured into the pipe to provide a good internal coating and helps prevent the hammer from running dry at any time. The grade of rock drill oil will be determined by the ambient temperature at the drilling site. If the ambient temperature is between 0 and 25 degree centigrade, then a 30 grade oil should be used. If the ambient temperature is greater than 25 degree centigrade, use a 50 grade oil.Bulroc supply their own recommended rock drill oil and this is detailed below, together with other brands of suitable oils.
MAKEBULROC
BPTEXACO
ESSOMOBILSHELL
TYPE 30 GRADELUBE T320
ENERGOL RD100100/1542 EPMAROX EP 150
ALMO 527TORCULA 100
TYPE 30 GRADELUBE T500
ENERGOL RD300320/1543 EPMAROX EP 320
ALMO 529TORCULA 320
TROUBLE PROBABLE CAUSE REMEDY
Drill bit blow holes blocked Unblock holes
Dirt inside drill Strip and clean drill
INOPERATIVE Worn or damaged par ts Replace damaged parts
DRILL Insuffic ient lubrication Check oil, level adjus t lube needle valve
Excessive lubrication Adjust lube needle valve
Hanging piston Piston stuck, Polish out the score marks
Insuffic ient air pressure Check compressor discharge and increaseto operat ional valve
Insuffic ient air pressure Increase discharge pressure
Dull drill bit Re-grind or change bit
Worn drill parts Replace worn par ts
SLOW PENETRATION Too much or too l ittle lubrication Check oil level and if necessary adjust tubeneedle valve
Dirt in drill Strip and clean
Low air pressure Increase air pressure
LOW RETURN AIRVELOCITY
Insuffic ient hole flushing air passingthrough hammer
Dril l or increase hole size through thepiston
Drill bit exhaust holes blocked Clean out blockage
Failed or damaged parts Overhaul drill
SPASMODIC Lack of oil Check lubrication
OPERATION Drill bit broken Replace bit
Dirt in drill Strip and clean
Troubleshooting
We recommend following the points listed below when removing a 'Down hole hammer' from service. This will ensure trouble free operation once the hammer starts work again.
The hammer should be stripped and cleaned and free of all water/moisture as possible.Bulroc 320 or similar rock drill oil should be poured into backhead (see chart below for quantity) allowing all parts to be coated throughout the hammer. Both ends of the hammer should be then covered to prevent the ingress of dirt, etc. It should be then laid horizontally in a dry environment ready for use next time.
Model Qty in UK Pints Qty in litre's
Hyper 241 2.5 1.42
If this procedure is followed then apart from protecting the hammer from corrosion it will protect the parts from premature wear and of course reduce 'down time' and eventual repair costs. However we strongly recommend that the hammer, especially if stored for any long periods of time should be stripped, cleaned, inspected and re-oiled prior use to be sure of smooth drilling.
13. Storage
top related