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J-67 International Association of Drilling Contractors Chapter J: Pumps Figure J4-37 Protection of Studs while using Wedge-type Pullers Figure J4-37. When wedge-type pullers are used on pumps with stud-type valve pet covers, a rag inserted in the crotch of the wedge will protect the studs. J-68 International Association of Drilling Contractors IADC Drilling Manual - Eleventh Edition Figure J4-38 Pulling the Valve Seat Figure J4-38. The valve seat is then pulled by striking the wedge with a sledge hammer. J-69 International Association of Drilling Contractors Chapter J: Pumps Figure J4-39 Valve Seat Puller Assembly Figure J4-39. This photograph shows the entire valve seat puller assembly immediately after it has been removed from the valve pot. Hydraulic jack pullers employ the same type puller head as the wedge type only the stem is longer for the jack. Place the jack over the stem on the two piece block and install the nut. Insert the "C" washer between the top of the jack and the nut. Release the fluid return valve to compress puller and bring the nut up as tight as possible. To prevent injury when the seat releases and pulls out of the deck, secure a safety chain around the pulling assem- bly, Figure J4-35. On duplex and single acting "L" head pumps all the valves are accessible from the top and may be changed easily. However, on single acting cylinder head pumps the intake valve is directly below the discharge valve and requires a special pulling tool, Figure J4-40. J-71 International Association of Drilling Contractors Chapter J: Pumps Figure J4-41 Washing Out the Valve Pot after Removing Valve Seat Figure J4-41. The entire valve pot should be washed immediately after removal of the valve seat. The deck should be carefully inspected for damage of any sign of fluid cutting. Any damage to pump deck should be repaired before installing new valve seats. Clean the pump deck thoroughly, removing any accumulation of rust or dried mud at the bottom of the machined tapered surface. If there is a shoulder at the bottom of the deck it must be thoroughly cleansed. A build-up of rust or mud in these areas will prevent the seat from seating properly in the taper, Figure J4-42 and Figure J4-43. J-73 International Association of Drilling Contractors Chapter J: Pumps The new valve seat is coated with a rust inhibitor, which must be thoroughly removed before installation in the pump. Remove the inhibitor with diesel oil or some other suitable solvent, and wipe dry with a clean cloth. The seat should be installed immediately after cleaning. If heat was used to remove the old seat, be sure the pump deck is cool to touch before attempting to install the new seat. Place the seat in the taper and press down firmly with your hand. This pressure should be sufficient to cause the seat to stick to the taper. There should be good contact all the way along the taper of the seat and the deck. If the seat will not stick in the taper and make good contact all the way around, remove the seat and inspect the mating surfaces again to be sure you have sufficiently removed the accumulation of rust and mud from the pump deck and that there are no nicks, burrs or pieces of weld spatter on the taper. Also check the part number to be sure it is the correct part for the pump. When the seat is firmly in place, most manufacturers recommend you place an old valve on the seat and strike several blows on the upper stem with an old pump rod or similar object to drive the seat into the deck. You can usually tell from the sound when it is properly seated. This step is very important. Do not rely on pump pressure to make this initial seal within the pump, since this may allow drilling fluids to seep between the seat and the deck taper causing leaks and wash outs. Before installing the valve in the pump, check the fit of the valve stem in the valve cover guide. If the valve cover guide is found to be egg-shaped, or if the clearance around the valve stem is greater than 1/16", the pot cover guide should be replaced. Now install the valve in the pump. NOTE: Never install old valves in new seat or new valves in worn seat, Figure J4-44. Figure J4-44 Never Install Worn Valves in New Seat (and vice versa) Remember when installing new valves in the pump, always use new springs to insure long trouble-free service from valves and seats; otherwise, check springs for signs of corrosion, loss of tension, physical abuse or wear. Before installing the pot covers, thoroughly clean the sealing surface. Lubricate both the sealing surface and the gasket with a general purpose grease. Remember: always use new gaskets. Prime the pump through all pots and install the pot covers. Make up to the proper torque recommended by the pump manufacturer. J-74 International Association of Drilling Contractors IADC Drilling Manual - Eleventh Edition J-5 Pump Problems, Failures and Analysis I. Priming and Starting Instructions Once the pump rod, cylinder heads and valve seats are installed, the pump is ready to be primed through all valve pots. Before installing the pot covers, be sure that the sealing surface and gaskets are cleaned and lubricated with general purpose grease. Make up the studs to the torque that is recommended by the manufacturer. If prechargers are available, they should be used so that the pump will be sure of getting complete prime and that entrained air in the mud pump will be easily worked out. The mud pump should be brought up to operating pressure gradually. On a duplex pump a crewman should cheek to make sure that the rod packing is getting sufficient lubrication. Rod packing leakage can be checked by momentarily pulling the rod lubricator line out of the gland nut and observ- ing if any mud is coming through the packing while the piston is moving toward the power end of the pump. Reinstall the lubrication line. On triplex pumps check the liner coolant system to assure adequate volume of coolant in the liner. Pot covers and tattle tale holes should be checked to be sure that there is no oozing of mud or excessive breathing. During the break-in period, the liner packing is also seating and expanding into all the voids and crevices. At the end of approximately a two hour period, the pump should be shut down and the liner packing retightened. Any movement of the liner will allow abrasive mud to get into the packing housing causing undue wear to the pump surfaces. Never tighten liner packing while the pump is under pressure. II. Pistons and Liners A. Excessive Wear of Liner and/or Piston Body In low pressure (less than 850 psi) service, when a total clearance of 3/32 or more occurs between piston flange and liner wall, the piston and/or liner should be replaced depending on wear of each. At medium (850 psi to 1600 psi) to high pressure, 1/16 clearance should be the limit. At extreme pressures (1600 psi to 3200 psi) and other severe operating conditions 0.040 clearance and the piston and/or liner can be considered "worn out". The contin- ued use of worn liners or pistons will result in short service life of piston rubbers. Do not use worn pistons in new liners or new pistons in worn-out liners. B. Streaking of Liner Bore and Piston Rubbers This condition is generally caused by excessive sand or other abrasive or foreign materials in the drilling fluid. Keep drill fluids as clean as possible and inspect the liners frequently when the pump is shut down. C. Pitted Liner This indicates corrosive conditions, pH of mull should be checked and increased if too low (below 7.2 pH). Corro- sion inhibitors may be considered. If corrosion is severe, the use of corrosion-resistant liners may be indicated. D. Concentration of Wear on One Side of Piston or Liner Normally a piston body will wear more on the lower side than the upper. If eccentric wear is excessive, or if it occurs at points other than the lower side, misalignment may be indicated. Check for worn crosshead slides, worn pump bores, worn stuffing boxes and junk rings, and unequal tightening of liner rod packing. J-75 International Association of Drilling Contractors Chapter J: Pumps E. Swollen and Torn Piston Rubbers The use of regular (natural rubber) piston rubbers in oil emulsion or oil contaminated mud will result in swelling and deterioration of the rubber. The use of oil resisting piston rubbers in oil emulsion muds with low aniline point oils can also result in similar swelling and deterioration. In the latter case, failure of other parts such as pipe protectors, blowout preventer rubbers, etc. will probably occur also, Figure J5-1. Figure J5-1 Buna N Rubber in Low Aniline Diesel Oil Figure J5-1. This "Buna-N" rubber has been run in an oil emulsion mud with a low aniline point diesel oil. Note the evidence of swelling of the face and chunks of rubber broken out of the body of the piston rubber caused by the deteriorating effect of the low aniline point diesel oil. The aniline point of the diesel oil being added to the mud must be above 150°F to prevent deterioration of all rubber goods which come in contact with the mud. F. "Burned" Piston Rubbers A starved suction or starting the pump without priming results in "burning" the piston rubbers in dry lines. Rapid failure will result after burning has occurred and it is sometimes difficult to trace or identify the failure. A "squeal- ing" in the cylinders when starting the pump or trying to pick up a prime indicates probable damage, Figure J5-2. J-77 International Association of Drilling Contractors Chapter J: Pumps Figure J5-3 Liner Damaged by Excessive Tighening of Liner Packing Figure J5-3. This liner was ruined by excessive tightening of the liner packing. The most common cause for this damage is failing to loosen the liner packing adjusting screws before tightening the cylinder head nuts. III. Fluid End Piston Rod and Packing A. Rod Broken Through Taper (Duplex Pumps) This type break can be caused by pump misalignment. Check for unequal wear on piston rod, piston body or liner for evidence of misalignment. Break can be caused by a notch or a stress concentration point or improper torque on the HP taper make-up so that the joint is not prestressed. B. Rod Broken in Cross-Head or Pony Threads Cross-head thread breakage is frequently due to out-of-square jam nuts, but pump misalignment can also cause such breakage. The use of an out-of-square jam nut can produce a stress concentration of up to ten times that of one having the proper fit, Figure J4-12. C. Rod Breakage in Body of Rod Failure of this type can be due to cracks started by hammer blows or other external rod damage. Don't hammer on the body of the rod to remove the piston, Figure J4-18. J-78 International Association of Drilling Contractors IADC Drilling Manual - Eleventh Edition D. Rod Pulled Apart in Taper End Threads (Duplex Pumps) These breaks are found exclusively in the smaller tapers and are generally the result of overtightening the piston and nut when making the piston up on a rod, Figure J4-24. E. Single Acting Piston Rod Problems Overtorquing of piston rod nut can cause rod breakage, thread galling and other installation and removal problems. Reference Figure J4-24 Torque for API Rod Connections for torque values. Inspect rod at clamp or thread end for cracks in flange and/or threads, as well as wear. Also inspect clamps for wear. With a clamp in good condition and tightened properly there must be no movement between clamp and rod. F. Rapid Wear or Streaking (Duplex Pumps) Overtightened or wornout gland packing, inadequate lubrication, or high sand content are chief causes. High pump pressures aggravate any streaking tendencies that may be present. If wear or streaking is concentrated on one side of rod, check pump alignment or check for uneven tightening of the packing gland. Recirculation of sand in the coolant system can also cause streaking. Too viscous a fluid so that fluid does not flow around entire rod also can contribute to streaking. G. Pitted or Streaked Rod Due to Pitting (Duplex Pumps) Corrosive drilling fluids or corrosive water lubrication are responsible. Use chrome-plated or hard coated piston red. H. Chrome Worn Off Rod (Duplex Pumps) Chrome plated piston rods have a hardened surface beneath the chrome plate and should not be replaced just because the chrome has worn off if chrome has worn in smooth. Replace when worn 1/16" to 3/32" total wear, depending upon operating conditions. At pressures above 2000 psi, 0.045 wear is generally all the wear that can be accommodated without excessive packing replacement. I. Washed Out Taper or Piston Pushed Up on Rod Taper (Duplex Pumps) Improper installation is responsible for the majority of these failures. Both piston and rod tapers should be clean and dry and proper torque used when piston is made up on rod, Figure J4-23. J. Short Packing Life (Duplex Pumps) Over tightening of packing, insufficient lubrication, high sand content, or use of worn-out rods with new packing are generally responsible. Worn junk rings, misalignment, or unequal tightening of the gland are other possible causes, as well as wash outs on worn stuffing boxes. IV. Valves and Seats A. Fluid Cut Sealing Members or Parts These failures are generally due to foreign material or lost circulation materials in the mud, or continued use of new sealing members on worn metal parts. Check all parts for wear, including upper valve guides, and replace if worn out. J-79 International Association of Drilling Contractors Chapter J: Pumps B. Fluid Cut Taper of Seat and Pump Deck Most cutting between the seat and deck is due to failure to realize the importance of proper installation and replacement of valve seats, Figure J4-43. Careless use of cutting torch in removing valve seats can result in damaging the deck so that the new seat will not seal properly. If a deck needs reworking, it should be done before a new scat is installed and qualified personnel should do it. C. Abnormal Wear or Breakage The use of new parts combined with worn-out mating parts frequently results in very rapid failure of either or both the new and worn part, Figure J4-44. Improper application sometimes results in similar failures of new parts. Proper selection of parts for the operating conditions will eliminate these troubles. Rapid wear results from high sand content in the drilling mud and if the sand content cannot be controlled or reduced, more frequent replacements will be necessary. Proper lift, with adequate guiding and correct springs are necessary for optimum valve life and performance. V. Reducing Pump Volume Pump manufacturers agree that reducing pump volume should be done be reducing pump speed and/or reducing liner size. If neither of these can be done, and under short emergency conditions, the following methods have been used. A. Duplex Pumps The discharge volume in any constant speed duplex pump may be reduced by removing valves as illustrated in Figure J5-4. Figure J5-4 Volume Reduction by Removing Valves FIGURE J5-4: Reduce volume by removing valves as shown. [...]... 50-100 hours use out of a part Schedule pump downtime, reduce pump downtime, and rig downtime, by changing parts in groups If a part is worn out, its companion is very nearly so By changing parts of the pump in a group, you eliminate the International Association of Drilling Contractors J-91 IADC Drilling Manual - Eleventh Edition continual going into the pump Since you can program a part and know when it... pump is never down while drilling is in progress Compare Figure J7-2 to Figure J7-3 where pump is shut down 12 times in 3600 hours compared to 28 times in 3600 hours Figure J7-2 Maintenance Schedule Chart Figure J7-3 Maintenance Schedule Chart II Establishing a Preventative Maintenance Program FIRST, run sufficient parts in the pump as to establish what can be expected for parts life For example, what... International Association of Drilling Contractors IADC Drilling Manual - Eleventh Edition The following industry representatives have contributed to the development and updating of this chapter: Bill Bingham, Chairman MH Koomey, Inc John Altermann Reading & Bates Drilling Company Paul Helfer MH Koomey, Inc Ralph Linenberger Global Marine Drilling Company Fred Mueller Reading & Bates Drilling Company Larry... barrier between the power end and piston rod chambers, confining gear oil to the power end and the splashing or spraying water and drilling mud to the rod chamber J-86 International Association of Drilling Contractors IADC Drilling Manual - Eleventh Edition Figure J6-3 Drilling Mud Contamination of Triplex Slush Pump Power End Figure J6-4 Faulty Wipers Cause Mud Contamination FIGURE J6-4: Faulty wipers... temperatures (above 200°F) or noise indicates possible bearing failure Complete bearing failure usually damages other pump parts Try to prevent complete bearing failure by changing when the above conditions are detected International Association of Drilling Contractors J-81 IADC Drilling Manual - Eleventh Edition VII Checklists A Checklist for Start Up 1 Coupling Aligned 2 Pump Full of Fluid 3 Suction Valve... permit accurate readings International Association of Drilling Contractors J-89 IADC Drilling Manual - Eleventh Edition I Pump Storage When slush pumps are to be put into storage certain precautions must be taken to prevent corrosive deterioration of pump components The cost of the precautionary measures is usually small compared to the loss of drilling time and expenses involved in reconditioning... second liner change the valve and seats If these products have similar life and can be operated as a unit, then we are ready to start programming, Table J7-1 Table J7-1 Parts Life Program FIRST: Run Sufficient Parts to Establish What Can Be Expected for Parts Life Liner Life Piston Life Rod Life Rod Packing Life Liner Packing Life Valve and Seat Life SECOND: Can The Products With Similar Life Be Operated... Association of Drilling Contractors J-93 IADC Drilling Manual - Eleventh Edition This is what programming does; pull the part just before failure III Advantages of programming: 1 If you know when an event is to occur, then plan your operation or activity around it 2 It is the most economical way to operate a No lost footage b No rig downtime c No damage to other parts because of failure d Reduce man-hours... Association of Drilling Contractors Chapter J: Pumps This Page Left Intentionally Blank International Association of Drilling Contractors J-95 Chapter K: BOP Equipment, Procedures Chapter K Well Control Equipment and Procedures International Association of Drilling Contractors K-1 IADC Drilling Manual - Eleventh Edition Table of Contents - Chapter K Well Control Equipment and Procedures Disclaimer and Credits... time most convenient to the contractor not when it is unexpected or costly to be down Parts that are left in will not be damaged and can be expected to run their full life Those few cents per hour wasted, Figure J7-1, by the item pulling apart with few hours life left on it, are more than saved Figure J7-1 If a Part is Replaced Before it Fails The "Cost per Hour" is out on the flat portion of the . rod to remove the piston, Figure J4-18. J -78 International Association of Drilling Contractors IADC Drilling Manual - Eleventh Edition D. Rod Pulled Apart in Taper End Threads (Duplex Pumps) These. splashing or spraying water and drilling mud to the rod chamber. J-88 International Association of Drilling Contractors IADC Drilling Manual - Eleventh Edition Figure J6-3 Drilling Mud Contamination. other pump parts. Try to prevent complete bearing failure by changing when the above conditions are detected. J-82 International Association of Drilling Contractors IADC Drilling Manual - Eleventh