tem fluidends mp

TREATING EQUIPMENT MANUAL

Fluid Ends

Section 10 April 2000

Page 7 of 87

CONFIDENTIAL

10.2 Maintenance Procedures

10.2.1 Routine Inspection

Plan to make systematic inspections of all fluid ends in service. The frequency of inspection will vary depending on the local pumping conditions, but a reasonable starting point would be every 100 deck hours or six months. Fluid end inspection can be scheduled with routine fluid end maintenance.

Figure 10-1 shows the areas that should be given special attention. For best results remove suction and discharge covers, valve seats, and packing and brass. The fluid end interior should be clean. Use a bright light for internal inspection.

Figure 10-1. Routine Inspection Areas


Page 8 of 87


Fluid Ends

CONFIDENTIAL

10.2.1.1 Things to look for:

1. Cracked Threads

Carefully examine threads for chipping and cracking. The outside thread on the suction cover gives the most problems. If the first or last thread is cracked no more than half way around, the cracked thread may be ground off. If more than half a thread is cracked the fluid end should be removed from service. (See Rebuild Guidelines, Fig. 10-2.) Dye penetrant is the best field method of checking for thread cracks. Examine mating covers and retainers.

2. Worn Bores

The cover bores must remain fairly smooth for the cover O-rings to seal properly. Inspect these bores for pitting and grooves. If these problems are evident, and the cover leaks, then a new O-ring groove may be cut to enable the O-ring to run on a smoother surface, or the cover bores can be built up and remachined.

3. Valve Seat Bores

The taper seat bores should be smooth and free of pitting or washouts. If washouts have occurred, see Rebuild Guidelines.

4. Cracks

Examine internal chamber for cracks. Dye checking may be required to confirm presence of cracks. Look at the intersection of packing bore and vertical bore, and above suction seat taper bore in the radius. If cracks are found, fluid end should be taken out of service. See Rebuild Guidelines for disposition of cracked blocks.

5. Grooves in Packing Bore

Examine packing bore for grooves. Grooves usually occur where packing lips contact the bore. Most fluid ends exhibit some grooving eventually. If you experience premature packing failure (brass and plungers must be in good condition), and groove depth exceeds .010 inch, packing bore wear may be the problem. Nominal packing bore size is plunger size plus one inch, +.002", -.000". See Rebuild Guidelines.

6. Discharge Port Washout

Examine discharge porting for washout. If washout is evident remove fluid end from service. See Rebuild Guidelines section, Fig. 10-2, for disposition of fluid end.


Fluid Ends


Page 9 of 87

CONFIDENTIAL

10.2.2 Rebuild Guidelines - Repair Welding

Repairs of the washout and cracking problems noted in "Routine Inspection" fall into two categories:

1) Areas experiencing cyclic stress

2) Areas in non-cyclic stress.

Figure 10-2. Rebuild Guideline - Repair Welding


Page 10 of 87


Fluid Ends

CONFIDENTIAL

10.2.3 Rebuild Guidelines - Authorized Welding

Repair techniques have been developed for the repair of damage in the non-cyclic areas of all fluid ends. Erosion, washout, and minor cracking of the packing nut threads, packing bore, suction bores, suction cover threads, suction and discharge seat bores, discharge cover bores, discharge cover threads, and all discharge porting above discharge valves is covered by this procedure.

Contact Operations Support-Pumping (OSP, formerly EMWD) for a current list of approved repair facilities. Fluid ends may be shipped directly to repair facility for repair quotation and/or repair.

Experience has shown that very little value comes from trying to repair cracks in cyclic areas of the fluid end. Generally speaking, the fluid end has a crack in it because it has progressed well into its fatigue life. Typically, cracks in this area are only a warning of things to come.

Two options are available for fluid ends with damage in cyclic areas. In some cases damaged suction cover threads can be machined out, new oversized threads machined in the block, and special suction cover retainers used. Also, minor washout damage to taper bores can sometimes be corrected by "lowering the decks"; a procedure whereby new taper bores are machined in the block. Both suction and discharge taper bores can be corrected by this method. Contact OSP (Operations Support-Pumping) for more details. All work must be done at approved shops. Major re-work (i.e. boring out the fluid end to the next larger plunger size) may be an option in some cases. This must be performed in Tulsa.

10.2.4 Packing A Pump

10.2.4.1 Packing Procedures

Dowell has standardized on double stack packing for all services except cementing. The standard arrangement of male adapter, male by female adapter, and female adapter separated by two packing rings (see Figure 10-3) is used in all Dowell and OPI series fluid ends. Keep in mind that a considerable amount of parts standardization was also achieved with this conversion; most components are used in both completion and stimulation services. As progress is made in the development and evaluation of new packing arrangements distribution of this information will be made to the field via Technical Alerts and Maintenance Bulletins. Check the OSP home page for the latest information available on packing and lubrication of pumps.


Fluid Ends


Page 11 of 87

CONFIDENTIAL

10.2.4.2 How to Pack a Pump

Figure 10-3. Standard Double Stack Packing Arrangement

1. Remove plungers, packing nuts, brass and packing from bores that are to be repacked. Use wood hammer handle or suitable puller to remove brass and packing. Keep plungers, brass, packing, etc., separate and in the order they are removed. In this way if a problem is observed you will be able to identify the bore.

2. Observe the packing bores at this time and if there is sand, dirt or other abrasives present, clean this out with a water hose, steamer or some type of pressure washing equipment. This is usually sufficient on frac pumps. It is absolutely necessary to have bore free of all debris before repacking as the clearance between brass and bore is only .002 - .004 inches.

3. Before starting to repack pump, all brass and packing nuts should be thoroughly cleaned and inspected for any damage.

4. If there is evidence that a plunger has been rubbing the brass, or if any discoloration exists indicating that the brass has been hot, the brass should be discarded. If any of these conditions are present it can be assumed that brass is too small or out of round.

5. The clearance between plunger O.D. and brass l.D. should always be .009 to .013 inches regardless of plunger size. Each piece of brass should also be checked for distortion by laying on a perfectly flat surface. Brass that is warped more than .005 should be discarded.

6. All new and used brass should be checked for minor nicks and scratches These may be removed with fine emery cloth or sandpaper. Always use #100 or finer grit. Never use a file to smooth up damage on the l.D. of brass.

7. Insert male adapter in bore of pump with a turning motion. If it locks-up or becomes stuck, tap gently with hammer handle until it becomes free. DO NOT pound or force into bore as this will distort the adapter.

8. Follow male adapter with first ring of double stack packing. DO NOT soak packing in oil; it must be installed dry.


Page 12 of 87


Fluid Ends

CONFIDENTIAL

9. Next install the male x female adapter with a rolling motion in the same manner as the male adapter was installed. DO NOT force if it becomes stuck.

10. Install second ring of double stack packing exactly as the first ring was installed.

11. Insert female adapter behind this ring in the same manner as first two adapters were installed.

12. Install lantern gland. If pump has quad ring adapter, install adapter next. On adapters of older design that have quad ring groove, DO NOT install quad ring. Quad ring to packing nut fit should be loose with .010 minimum clearance.

13. Inspect plungers for nicks or scratches. Clamp on type plungers should be inspected in the flange area for damage. Nicks or high spots will affect alignment as well as the ability of the clamp to keep plunger tight. Plungers should be replaced if the plunger surface has any deep nicks or scratches or if the coating has lost its sheen and has become dull in appearance.

14. Plunger threads must be clean and free of foreign particles. See the "Plungers" portion of this section for more details.

15. With an oil soaked shop towel, thoroughly oil inside of packing and brass. Coat plunger with oil and install in pump bore.

16. Threaded plungers should be screwed on with a 24" pipe wrench and snapped tight with a 6# hammer.

17. Bolts in clamp on plungers should be torqued to 70-75 ft. Ib. with an equal amount of spacing on each side of clamp.

18. After all packing and plungers are installed, tighten all packing nuts as tight as possible with a standard spanner wrench (no extensions on handle). Start unit up and with pump turning over slowly, make sure that all plungers are oiling. Continue to tighten packing with pump turning over until packing nut cannot be tightened further with a standard spanner wrench. This will usually take 20 to 30 minutes. It is extremely important that pump is turning while packing is being tightened.

CAUTION: Pumps with clamp-on plungers can be very hazardous as the clamp to packing nut clearance constitutes a finger trap.


Fluid Ends


Page 13 of 87

CONFIDENTIAL

10.2.4.3 Plunger Lube System

Progress is continually being made in lube oil systems for the plunger and packing. For the latest in what is available and has been commercialized consult the OSP (FORMERLY EMWD) home page.

URL: http//www.dowell.slb.com/Hub/index.cfm?uid=uid6806

Choice of lubricant is not critical in plunger lube systems. New or recycled and filtered lubricants, from chassis grease to 10W oil, have all been used successfully. Reservoir and lubricant cleanliness is important, however. The divider blocks used on most systems tolerate only filtered oil.

Technical Alerts and Maintenance Bulletins will communicate the latest advancement.

10.2.5 Plungers

Plunger maintenance and inspection is straightforward. Two areas require attention: surface finish of the body and the condition of the connection to the pony rod (crosshead).

Surface Finish: Plungers are manufactured with a coating of nickel-chromium alloy approximately .020 inches thick. New plungers have a surface finish or 8 micro inches and have a bright, mirror-like appearance. A plunger in service gradually loses this finish. The surface will gradually turn dull gray, and if it remains in service long enough deep grooves and pits may develop.

As can easily be imagined, packing life is directly related to the condition of the plunger's surface. Attempts to save money by delaying plunger re-coating simply result in increased maintenance costs in packing. The object is to reduce overall maintenance cost by scheduling re-packing and plunger re-work at the optimum intervals.

The best way to determine when plungers need re-work is to keep local records of plunger condition and packing life. In general, for stimulation service dull plungers (gray, no surface sheen) should be replaced.

Connecting End: Burrs, nicks or bent flanges can effect clamp-on plunger alignment and shorten plunger life. Be sure to check plungers before and after re-coating for damage in this area. Threads on the threaded plungers should be clean, free of overspray and not have nicks or burrs that will hinder make-up on the crosshead extension (pony rod). The end face of the connecting end of the plunger must be clean and free of nicks, burrs or dents.


Page 14 of 87


Fluid Ends

CONFIDENTIAL

Plunger Re-Surfacing: Dowell specification 509748000 for plunger re-surfacing is available to aid field locations in obtaining good workmanship and correct dimensions on recoated plungers. Consult OSP (formerly EMWD) for the availability of a list of approved re-surfacing shops.

10.2.6 Valves and Seats

Considerable effort has gone into improving the life of valves and seats in the last few years. Improvements in seat metallurgy and valve design have resulted in longer component life, a lot of new part numbers, and new terms such as "thin leg" and "bonded insert". This section provides maintenance and application information, (correct part numbers can be found in the "Valve and Seat Quick Reference" portion of the parts lists, Table 10-4) plus an explanation of the new terminology.


Fluid Ends


Page 15 of 87

CONFIDENTIAL

10.2.7 Terminology

Figure 10-4. Valve and Seat Terminology

The following specialized terms are used in describing valves and seats: Insert: Rubber Insert Black in color, always stretch-on Urethane Insert Yellow in color, may be bonded or stretch-on Bonded or Molded

Insert Urethane insert permanently attached to valve body - insert is not replaceable

Stretch-on Insert Conventional removable insert - can be rubber of urethane Valve: Hi Flow Special oversized bore version (same overall dimensions) available for some applications.

Do not mix with regular seat in same pump Thin Leg Flat sided and thinner legs that have replaced conventional legs on all versions Hi Strike/Low Strike Refers to contact width of insert. Low strike with the wider insert is standard 10,000 PSI Disc

15,000 PSI Disc 22,500 PSI Disc

Refers to the pressure at which the rupture disc ruptures. Used on suction valves only.

Seat: Hi Flow Special oversized bore version. Do not mix with regular valve Twin Angle Special chamfered shoulder (see Figure 10-4) - only to be used where indicated


Page 16 of 87


Fluid Ends

CONFIDENTIAL

10.2.8 Routine Maintenance Periodic inspection of valves and seats is necessary, of course, for good pump performance. Recommended inspection intervals and anticipated component life will vary widely depending on the type of service. Neglect in this area will result in poor pump performance and eventually major damage to the fluid end.

Periodically examine valve inserts for damage. Minor nicks or cracking is acceptable. If large chunks (1/8 inch or larger) of insert are missing, replace insert on stretch-on valves or discard valve if insert is bonded. Any valves showing evidence of washout on body should be discarded. In the same manner, seats showing evidence of washout should be pulled immediately to prevent major fluid end damage. See Figure 10-5.

Figure 10-5. Valve and Seat Washout Locations

Examine seat sealing face for wear. Gauges are available to simplify judging seats. See "MacClatchie Valve Seat Wear Gages", Table 10-1, for the correct gage.

Valve seats should be removed only with the MacClatchie puller (See "MacClatchie Seat Puller Assembly", Figure 10-6 on following pages). Operating instructions follow the parts listings. Do not cut out seats with a torch!

NOTE: Urethane Inserts, both stretch on and bonded, have a limited shelf life. Store In a cool dry place. Shelf life as short as one year may be encountered in hot humid environments.


Fluid Ends


Page 17 of 87

CONFIDENTIAL

Table 10-1. MacClatchie Valve Seat Wear Gauges

Seat Gauge Assembly Application Mac P/N Dowell P/N Mac P/N Dowell P/N TT03, TF04-5 (Suct) 45522 512048000 47072 517644000 TU01, TM05-7, TR08, TS02, MM01 QG02, QL03 45595 511630000 470510 454465000 MD01, ME02, ME03, 45538 511306000 470510 454465000 MF02, TD04, TE04, TE05, TF04-5(Dis), TF06, TF07, TF09, TG05, TG06, TH05, TH06 TL05, TL06, TL07, QG01, QL02, FOPI, EOPI, EOPI2 Ql01, HOPI, HOPI2,IOPI2 45476 510119000 47074 517645000 MJ01, MN01-2, MP02 45550 512051000 47056 454467000 TN01, JOPI, MJ02, 45500 512052000 47076 517646000 MP03, TJ04, TK04 OPI 4 1/2-5 45494 512053000 47076 — (1300/1800) OPI 5 1 /2-6 45549 512054000 47053 — (1300/1800) OPI 6 1/2-7 1/2 45513 519407 — — (1300/1800)


Page 18 of 87


Fluid Ends

CONFIDENTIAL

Figure 10-6. MacClatchie Seat Puller Assembly

Item Description Dowell P/N Mac P/N 1 Pump, Hydraulic 425735000 — 2 Hose, Hydraulic 425736000 — 3 Coupler 425740000 — 4 Handle, Tee 425737000 174656 5 Nut, Puller 425738000 109891 6 Plunger 425739000 109732 7 Base, Plate 425741000 174773 8 O-rings (Not Shown) 514794000 109892 514795000 109893 9 Mandrel, Puller 496484000 174695 10 Nut, Stop 425742000 105191

(All quantities are 1)


Fluid Ends


Page 19 of 87

CONFIDENTIAL

Table 10-2. Application List for MacClatchie Head Assemblies

Seat Head

Application Mac P/N Dowell P/N Assembly Mac P/N

Adapter Mac P/N

Body Mac P/N

Pin Mac P/N

TT03, TF04-5 (Suct) 45522 512048000 174760 174762 174761 * TU01, TM05-7 TR08, TS02, MM01 QG02, QL03 45595 511630000 174741 174743 174742 174744 MD01, ME02, ME03, 45538 511306000 174741 174743 174742 174744 MF02,TD04, TE04, TE05, TF04-5(DIS), TF06, TF07, TF09, TG05, TG06, TH05, TH06, TL05, TL06, TL07, QG01, QL02, FOPI, EOPI, EOPI2 Ql01, HOPI, HOPI2, IOPI2 45476 510119000 174773 174775 174774 174776 MJ01, MN01-2, MP02 45550 512051000 174773 174775 174774 174776 TN01, JOPI, MJ02 45500 512052000 174752 174748 174753 174749 MP03, TJ04, TK04 OPI 4 1/2-5 45494 512053000 174741 174743 174742 174744 (1300/1800) OPI 5 1/2-6 45549 512054000 174784 174775 174785 174776 (1300/1800) OPI 6 1/2-7 1/2 45513 519407000 174752 174748 174753 174749 (1300/1800)

* Modified design uses 2 MacClatchie P/N 117940 spring pin, 1 P/N 107852 spring pin, 1 P/N 174764 spring and 1 P/N 109876 O-ring.

See MacClatchie seat puller assembly drawing (Figure 10-6) for parts identification.


Page 20 of 87


Fluid Ends

CONFIDENTIAL

Operating instructions for the valve seat puller are as follows:

1. Remove the covers, springs, and valves from the fluid end.

2. Assemble seat puller as follows:

A. Screw puller nut onto mandrel and run down part way.

B. Install T-handle into top of mandrel.

C. Install plunger into base plate with O-rings down.

D. Insert mandrel into base plate.

E. Install puller stop nut below base assembly.

F. Attach the proper size head assembly. (See Table 10-2)

3. Lower head assembly through seat to be pulled, and position the base plate on top of the fluid end over the discharge opening.

4. Shake the puller assembly to make the puller body seek a horizontal position underneath the seat to be pulled.

5. Screw the puller nut down against the pressure plate until the body of the head assembly fits snugly against the bottom the seat.

6. Attach the hydraulic pump hose to the 5000 PSI pressure gage on the base plate and operate the pump until the seat comes free.

NOTE: Never exceed 3000 PSI on pressure gauge. Exceeding this pressure may result in puller component failure and injury.

10.2.8.1 Valve Installation

After removal of seats, examine tapered fluid end bores where seats fit for washouts or erosion. If this has occurred remove fluid end from service. See the following page of this section for Repair Guidelines.

Wipe tapered seat bores with a clean cloth. Light corrosion or nicks can be touched up with emery cloth. Taper bore must be clean and smooth for the valve seat to seat properly.

Remove replacement seat from package, install O-ring, wipe O.D. of seat with clean cloth before installation. Install seats dry. Seat may be partly seated using an old valve (without insert) and a steel bar to drive it. Most seats will require up to 3,000 or 4,000 PSI hydraulic (pumping) pressure to fully seat. In all designs the shoulder will contact the fluid end when the seat is fully seated. Use care when installing seats. Cleanliness is important. Improper seat installation procedures can cause major pump failures!


Fluid Ends


Page 21 of 87

CONFIDENTIAL

10.3 Troubleshooting - Fluid End

Symptom Cause Correction See Page Pump runs rough 1. Worn valve and insert 1. Replace valve 16 2. Worn valve seat 2. Check with seat gage or replace

seat 17

3. Broken valve spring 3. Replace spring 4. Cavitation 4. Slow pump, boost suction pressure,

tighten suction connections, add hoses

5. Object under valve 5. Remove object 6. On units so equipped stabilizer

malfunction 6. Service Stabilizer 86

7. Valve float 7. Replace springs if problem persists try stiffer springs if available

8. Air entering suction 8. Tighten suction connections Short packing Iife 1. Clogged lubricator line 1. Service and clean the divider block

and check valve.

2. Dull or worn finish on plunger 2. Replace plungers 13 3. Improper installation or break-in 3. See “Packing a Pump” in this

section 11

4. Worn packing bore 4. Replace fluid end if grooves more than .010” deep

Packing smokes 1. No oil 1. Check lubrication reservoir 2. Clogged lubricator line 2. Clean divider block and check valve 3. Packing nut too tight 3. Loosen nut slightly; See“Packing a

Pump” 11

Packing leaks 1. Worn out or too loose 1. Tighten or replace packing 2. Worn plungers 2. Replace plungers Uneven Brass Wear 1. Out of spec brass 1. Replace defective components 11 2. Fluid-end/power end

misalignment 2. Check for misalignment. Consult OSP, formerly EMWD, for more details

Priming is difficult 1. Cocked valve 1. Inspect and straighten valve 2. Broken valve spring 2. Replace spring 3. Loose suction hose connection 3. Tighten Leakage at discharge outlet

1. Bad O-ring on bushing 1. Replace O-ring

2. Washed out discharge bore 2. Replace or repair fluid end 11

tem fluidends mp

Documents

treating equipment

standard spanner

double stack

puller nut

female adapter

taper bores

cover bores

fluid end