failing mud pump parts quotation

A mud pump is a reciprocating piston/plunger pump designed to circulate drilling fluid under high pressure (up to 7,500 psi (52,000 kPa)) down the drill string and back up the annulus. A duplex mud pump is an important part of the equipment used for oil well drilling.

Duplex mud pumps (two piston/plungers) have generally been replaced by the triplex pump, but are still common in developing countries. Two later developments are the hex pump with six vertical pistons/plungers, and various quintuplex’s with five horizontal piston/plungers. The advantages that Duplex mud pumps have over convention triplex pumps is a lower mud noise which assists with better Measurement while drilling and Logging while drilling decoding.

Use duplex mud pumps to make sure that the circulation of the mud being drilled or the supply of liquid reaches the bottom of the well from the mud cleaning system. Despite being older technology than the triplex mud pump, the duplex mud pumps can use either electricity or diesel, and maintenance is easy due to their binocular floating seals and safety valves.

A mud pump is composed of many parts including mud pump liner, mud pump piston, modules, hydraulic seat pullers, and other parts. Parts of a mud pump:housing itself

Duplex pumps are used to provide a secondary means of fuel transfer in the event of a failure of the primary pump. Each pump in a duplex set is sized to meet the full flow requirements of the system. Pump controllers can be set for any of the following common operating modes:Lead / Lag (Primary / Secondary): The lead (primary) pump is selected by the user and the lag (secondary pump operates when a failure of the primary pump is detected.

Alternating: Operates per Lead / Lag (Primary / Secondary) except that the operating pump and lead / lag status alternate on consecutive starts. A variation is to alternate the pumps based on the operating time (hour meter) of the lead pump.

abstractNote = {Failure of a liner seal is one of the more critical failures on a mud pump because this seal interfaces with the pump body. Therefore, failures, usually damage the pump body, leading to repair or replacement of the fluid end itself. One of the more common liner seal problems involves counter-bore-type seals. This type of seal is easily affected by two aspects of the problem that are found in the mud pump fluid end-wear and foreign matter in the seal groove. Factors relative to difficult liner removal are discussed. Piston damage, careless seal installation and corrosion damage are also examined.},

abstractNote = {This article points out that the reason for the difficulty in diagnosing alignment problems in a mud pump is that the fluid end can be misaligned in a number of ways, and in a number of places. Explains that problems with liners, pistons, rods, and rod packings often can be traced to a fluid end that is not aligned with the pump"s power end. Recommends that in problem pumps, the piston orientation should be marked on the pistons or on the rod before the pistons are removed from the liner. The tops of the liners also should be marked before they are removed from the pump as well.},

Adjust or replace these bearings at first sign of wear. The bearings in the crank end are babbitt lined steel shells, adjustable for wear by removing shims and easily replaced when completely worn. These bearings should be watched closely and adjusted at first signs of looseness.. You will note on series 3400, 3800, 3500, and 3900 pumps, that the shims do not completely fill the outer gap between rod and cap casting, although the connecting rod bolts are tight. This is because the faces of the shell bearings project slightly beyond the faces of the rod and cap castings, and the shims are gripped only between the faces of the bearing halves. Do not try to close this outer gap by tightening the connecting rod bolt as it will put an excessive strain on the bolts.

To check for wear, place a wrench on the top connecting rod bolt and shake the rod parallel to the crankshaft. (The pressure must be relieved from the liquid end of the pump, so that the pump"s mechanism is free to move.) If the rod bearing moves without resistance, the bearing may be too loose and need adjusting. If the bearing does need adjusting, remove shims until you cannot shake the rod, then add .005" shims one at a time until there is little side movement. Be sure to torque rod bolt nuts to proper value for each adjustment. Oil clearance should be checked with Plastigage (available in most parts stores). Wipe crankshaft journal clean of any oil, place a strip of Plastigage on the crankshaft journal and tighten rod cap to the proper torque value. Once tightened, remove rod cap and measure oil clearance with scale on Plastigage package. See oil clearance chart. (NOTE: If you are making this adjustment after having had the crossheads out, be sure that the oil holes in the rod are pointing up. The "up" side is indicated by matching numbers stamped on the cap and rod at the split between them. These numbers should be the same on each rod and should be on the top side of the crankshaft.) Rotate the shaft by hand and if there is any hard drag or tight spots in the bearing, add another 0.005" shim. After this bearing is properly adjusted, loosen bolts a few turns and repeat the above operation on the other bearings. After all bearings have been adjusted.

Torque all connecting rod bolt nuts back to proper value. Again rotate the pump by hand to check for excessive drag and tight spots. If none, the pump should be ready for operation.

If the pump cannot be rotated by hand due to the drive being enclosed, care must-be taken: not to over-tighten the bearings, since they cannot be checked by rotating the pump. When bearings are adjusted by this method, watch carefully for overheating when the pump is put into operation.

It is usually better to have a bearing a little too loose than too tight. A slightly loose bearing will cause very little trouble because of the slow operating speeds of the pump, but a tight bearing will overheat and the babbitt may melt or pull. Normal precautions must be taken to insure cleanliness of parts upon their assembly.

To check for wear, place a wrench on the top connecting rod bolt and shake the rod parallel to the crankshaft. (The pressure must be relieved from the liquid end of the pump so that the pump"s mechanism is free to move.) If the rod bearing moves without resistance, the bearing may be too loose and need adjusting. If the bearing does need adjusting, remove shims until you cannot shake the rod, then add .005" shims one at a time until there is a little side movement. Be sure to torque rod bolt nuts to proper value for each adjustment. (NOTE: If you are making this adjustment after having had the crossheads out, be sure that the oil holes in the rod are pointing up. The "up" side is indicated by matching numbers stamped on the cap and rod at the split between them. These numbers should be the same on each rod and should be on the top side of the crankshaft.) Turn the shaft by hand and if there is any hard drag or tight spots in the bearing, add another .005"" shim. After this bearing is properly adjusted, loosen bolts a few turns and repeat the above operation on the other bearings. After all bearings have been adjusted, torque all connecting rod bolt nuts back to proper amount. Again turn the pump by hand to check for excessive drag and tight spots. If none, the pump should then be ready for operation.

If the pump cannot be rotated by hand due to the drive being enclosed, the bearings may be completely adjusted by shaking the bearing on the shaft as stated above. Care must be taken not to over-tighten the bearings since they cannot be checked by rotating the pump by hand. When bearings are adjusted by this method, they must be watched carefully for overheating when the pump is put into operation.

Alternatively, plastic gauge strips, found in most parts stores may be used to adjust these bearings. It is usually better to have a bearing a little too loose than too tight. A slightly loose bearing will cause very little trouble because of the slow operating speeds of the pump, but a tight bearing will overheat and the babbitt may melt or pull. with experience, an operator can tell by feel when the bearings are properly adjusted. Normal precautions must be taken to insure cleanliness of parts upon their assembly. All wrenches used in adjusting these bearings are standard wrenches.

A Mud Pump may have many changeable parts, such as liner, piston, extension rod, pulsation dampener, valve, clamp, etc. Lake Petro could provide 100% interchangeable parts of many common brands of pump. We offer Liners with Ceramic (Zirconia and Aluminium oxide) and Steel (Metal and Bi-metal) materials. Piston assembly is the important spare parts and expendable parts of oil drilling mud pumps. Mud pump valve assy include valve body, valve seat, valve insert (valve rubber ). Pulsation Dampener is usually installed on the discharge line to reduce the fluctuation of pressure and displacement of the drilling mud pump. Fluid End Module is an important component of the hydraulic pump end of the mud pump.

You can find our high-performance mud pumps at some of the largest oil and natural gas drilling operations on the planet. Now, we’re ready to supply one of our mud pumps to you.

Looking for a mud pump for sale? Bridges Equipment has the biggest inventory of rebuilt duplex and triplex mud pumps and pump packages ready to ship. Unlike some suppliers, we completely rebuild our mud pumps to OEM standards and guarantee our work from 90 days up to six months against major failure.

Our fabrication facility customizes mud pumps, equipment, and pump packages to meet the needs of operations large and small, across the nation and around the world. Whether you need a custom-fabricated mud pit or a unitized pump package, we have the expertise to get it done.

Nothing wastes time and money like waiting on parts. With two supply stores stocked with the fluid ends and other mud pump parts you need to keep your operation running, and the field mechanics to install them, we can help keep your operation up and running.

Customizability. Functionality. Quality. Reliability. You’ll find these attributes and more in every mud pump, mud pump part or mud pump package we have available for sale or rental.

GDEP is the original creator of the drilling pump and continues to set the standard for durable, high-quality drilling pumps that can withstand the world’s toughest drilling environments. Starting with our PZ7 and rounding out with the market"s most popular pump, the PZ1600, our PZ Series of pumps are the perfect choice for today"s high-pressure drilling applications.

Unexpected failure of mud pumps during drilling operations can result in non-productive time (NPT) and increase well construction cost. Several prior studies and implementations of condition-based maintenance (CBM) systems for mud pumps have failed to provide a generalized solution for the variety of pump types encountered in the field, in particular by failing to detect damage early enough to mitigate NPT. Our research is aimed at improving upon this situation by developing a practical, generally-applicable CBM system for mud pumps.

In the study reported here, a laboratory test bed with a triplex mud pump was used to collect data to test a new approach to mud pump CBM. Artificial damage was introduced to the two most frequently replaced parts of the pump, i.e., the valve and piston. An accelerometer and an acoustic emission (AE) sensor were used to collect experimental data. Based on this data, an anomaly detection algorithm was constructed using a one-class support vector machine (OC-SVM) to pin-point the early onset of mud pump failure. The CBM methodology thus developed does not require prior knowledge (data) of the mud pump itself or of the failures of its components. This is key to it being more widely deployable.

The trained machine-learning algorithm in the test setup provided an accuracy greater than 90% in detecting the damaged state of the valve and piston. Only the characterization of the normal (i.e., non-damaged) state data was required to train the model. This is a very important result, because it implies that the sensors can be deployed directly onto mud pumps in the field – and additionally, that the first few hours of operation are sufficient to benchmark normal operating conditions. Also, it was observed that a multi-sensor approach improved the accuracy of detection of both the valve and piston damage. The system is able to detect early-stage damage by combining the cumulative sum control chart (CUSUM) with the damage index developed in this project.

This work is the first attempt at applying semi-supervised learning for CBM of mud pumps. The approach is applicable for field use with very little or no prior damage data, and in various working conditions. Additionally, the system can be universally deployed on any triplex pump and efficiently uses the data collected in the first few hours of operation as a baseline. Consequently, the practicality and scalability of the system are high. It is expected to enable the timely maintenance of critical rig equipment before catastrophic damage, failure and associated downtime occurs. The system has been deemed promising enough to be field-trialed, and is currently being trialed on rigs in North America.

The Baoji/Bomco F1000 Triplex mud pump has a max. working pressure of 5,000PSI and a 6-3/4" liner size. This model is the first choice for the medium and deep dr... More Info

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Mud Pumps - Mud Pump Parts & Complete Units: Liners, Pistons, Rubbers, Rods, Valves, Seats, Springs, Inserts (Bean, BJ, CAT, EMSCO, Ellis Williams, FMC, Failing, GASO, Gardner Denver... More Info

Mud Pumps - Mud Pump Parts & Complete Units: Liners, Pistons, Rubbers, Rods, Valves, Seats, Springs, Inserts (Bean, BJ, CAT, EMSCO, Ellis Williams, FMC, Failing, GASO, Gardner Denver... More Info

Mud Pumps - Mud Pump Parts & Complete Units: Liners, Pistons, Rubbers, Rods, Valves, Seats, Springs, Inserts (Bean, BJ, CAT, EMSCO, Ellis Williams, FMC, Failing, GASO, Gardner Denver... More Info

Mud Pumps - Mud Pump Parts & Complete Units: Liners, Pistons, Rubbers, Rods, Valves, Seats, Springs, Inserts (Bean, BJ, CAT, EMSCO, Ellis Williams, FMC, Failing, GASO, Gardner Denver... More Info

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Mud Pumps - Mud Pump Parts & Complete Units: Liners, Pistons, Rubbers, Rods, Valves, Seats, Springs, Inserts (Bean, BJ, CAT, EMSCO, Ellis Williams, FMC, Failing, GASO, Gardner Denver... More Info

Mud Pumps - 1 - Rebuilt Gardner Denver PZ-9 Mud Pump Package, New Caterpillar C-27, 1050 HP diesel engine. Belt-driven. comes with pulsation dampener, discharge block, precharge, li... More Info

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Mud Pumps - Mud Pump Parts & Complete Units: Liners, Pistons, Rubbers, Rods, Valves, Seats, Springs, Inserts (Bean, BJ, CAT, EMSCO, Ellis Williams, FMC, Failing, GASO, Gardner Denver... More Info

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(1) The diesel engine speed of the main pump station is too low, the fuel supply is insufficient, and the supply pressure of the hydraulic system is too low;

(2) The hydraulic system of the mud pump supplied by the main pumping station is faulty or the pressure adjustment of the overflow valve in the system is low and the internal leakage is serious, and the supply pressure is insufficient;

(1) Increase the speed of the diesel engine at the main pump station (n is greater than or equal to 1500 r/min), increase the fuel supply of the motor, and increase the effective working pressure of the hydraulic system (above 10MPa);

(1) Reason analysis: The diesel engine speed of the main pumping station is low and the fuel supply is insufficient, resulting in insufficient flow of the water pump and the pressure cannot rise.

(2) Solution: Increase the diesel engine speed of the main pump station (n is greater than or equal to 1500 r/min), increase the motor oil supply, increase the water pump flow, and then increase the pressure; unscrew the pressure gauge and fill the buffer with oil or After replacing the rubber diaphragm, fill it with engine oil.

The reasons and solutions for the failures that often occur in mud pump operations are listed above. The equipment failures caused by specific reasons in the use of mud pumps are different. Reasonable use and maintenance of the equipment can extend the service life of the equipment.

The piston is one of the parts that most easily become worn out and experience failure in mud pumps for well drilling. By imitating the body surface morphology of the dung beetle, this paper proposed a new type (BW-160) of mud pump piston that had a dimpled shape in the regular layout on the piston leather cup surface and carried out a performance test on the self-built test rig. Firstly, the influence of different dimple diameters on the service life of the piston was analyzed. Secondly, the analysis of the influence of the dimple central included angle on the service life of the piston under the same dimple area density was obtained. Thirdly, the wear of the new type of piston under the same wear time was analyzed. The experimental results indicated that the service life of the piston with dimples on the surface was longer than that of L-Standard pistons, and the maximum increase in the value of service life was 92.06%. Finally, the Workbench module of the software ANSYS was used to discuss the wear-resisting mechanism of the new type of piston.

The mud pump is the “heart” of the drilling system [1]. It has been found that about 80% of mud pump failures are caused by piston wear. Wear is the primary cause of mud pump piston failure, and improving the wear-resisting performance of the piston-cylinder friction pair has become the key factor to improve the service life of piston.

Most of the researchers mainly improve the service life of piston through structural design, shape selection, and material usage [1, 2]. However, the structure of mud pump piston has been essentially fixed. The service life of piston is improved by increasing piston parts and changing the structures of the pistons. However, the methods have many disadvantages, for example, complicating the entire structure, making piston installation and change difficult, increasing production and processing costs, and so on. All piston leather cup lips use rubber materials, and the material of the root part of the piston leather cup is nylon or fabric; many factors restrict piston service life by changing piston materials [3]. Improving the component wear resistance through surface texturing has been extensively applied in engineering. Under multiple lubricating conditions, Etsion has studied the wear performance of the laser surface texturing of end face seal and reciprocating automotive components [4–6]. Ren et al. have researched the surface functional structure from the biomimetic perspective for many years and pointed out that a nonsmooth surface structure could improve the wear resistance property of a friction pair [7, 8]. Our group has investigated the service life and wear resistance of the striped mud pump piston, and the optimal structure parameters of the bionic strip piston have improved piston service life by 81.5% [9]. Wu et al. have exploited an internal combustion engine piston skirt with a dimpled surface, and the bionic piston has showed a 90% decrease in the average wear mass loss in contrast with the standard piston [10]. Gao et al. have developed bionic drills using bionic nonsmooth theory. Compared with the ordinary drills, the bionic drills have showed a 44% increase in drilling rate and a 74% improvement in service life [11]. The present researches indicate that microstructures, like superficial dimples and stripes, contribute to constituting dynamic pressure to improve the surface load-carrying capacity and the wear resistance of the friction pair [12–21].

In nature, insects have developed the excellent wear-resistant property in the span of billions of years. For instance, the partial body surface of the dung beetle shows an irregularly dimpled textured surface with the excellent wear-resistant property that is conducive to its living environment [7, 8, 22]. The dung beetle, which is constantly active in the soil, shows a body surface dimple structure that offers superior drag reduction. These dimples effectively reduce the contact area between the body surface and the soil. Moreover, the friction force is reduced. Therefore, the dung beetle with the nonsmooth structure provides the inspiration to design the bionic mud pump piston. This paper proposed a new type of piston with dimpled morphology on its surface and conducted a comparative and experimental study of different surface dimpled shapes, thus opening up a new potential to improve the service life of the mud pump piston.

A closed-loop circulatory system was used in the test rig, which was built according to the national standard with specific test requirements. The test rig consisted of triplex single-acting mud pump, mud tank, in-and-out pipeline, reducer valve, flow meter, pressure gauge, and its principle, as shown in Figure 1. Both the pressure and working stroke of the BW-160 mud pump are smaller than those of the large-scale mud pump, but their operating principles, structures, and working processes are identical. Therefore, the test selected a relatively small BW-160 triplex single-acting mud pump piston as a research object, and the test results and conclusion were applicable to large-scale mud pump pistons. The cylinder diameter, working stroke, reciprocating motion velocity of piston, maximum flow quantity, and working pressure of the BW-160 triplex single-acting mud pump were 70 mm, 70 mm, 130 times/min, 160 L/min, and 0.8–1.2 MPa, respectively.

The mud pump used in the test consisted of water, bentonite (meeting the API standard), and quartz sand with a diameter of 0.3–0.5 mm according to actual working conditions. The specific gravity of the prepared mud was 1.306, and its sediment concentration was 2.13%. Whether mud leakage existed at the venthole in the tail of the cylinder liner of the mud pump was taken as the standard of piston failure. Observation was made every other half an hour during the test process. It was judged that the piston in the cylinder failed when mud leaked continuously; its service life was recorded, and then it was replaced with the new test piston and cylinder liner. The BW-160 mud pump is a triplex single-acting mud pump. The wear test of three pistons could be simultaneously conducted.

The mud pump piston used in the test consisted of a steel core, leather cup, pressing plate, and clamp spring. The leather cup consisted of the lip part of polyurethane rubber and the root part of nylon; the outer diameter on the front end of the piston was 73 mm, and the outer diameter of the piston tail was 70 mm, as shown in Figure 2. We proceeded in two parts during the design of the dimpled layout pattern because the piston leather cup consisted of two parts whose materials were different. The dimples at the lip part of the leather cup adopted an isosceles triangle layout pattern, and the dimples at the root part were arranged at the central part of its axial length, as shown in Figure 3(a). Dimple diameter (D, D′), distance (L), depth (h), and central included angle (α) are shown in Figure 3. The dimples on the piston surface were processed by the CNC machining center. Since then, the residual debris inside the dimples was cleaned.

Table 1 shows that average service lives of L-Standard, L-D1, L-D2, and L-D3 were 54.67 h, 57.17 h, 76.83 h, and 87.83 h, respectively. Therefore, the mud pump pistons with dimples provide longer service life than the L-Standard piston. As the dimple diameter increases, the piston service life was improved, and the largest percentage increase of the service life was 60.65%. The service life of the L-D4 piston was about 81.17 h, which increased by 7.94% compared with that of the L-D2 piston, indicating that the piston with dimples at the leather cup root could improve piston service life.

Figure 4 illustrates the surface wear patterns of pistons with different dimple diameters in the service life test. Figures 4(a) and 4(a′) show wear patterns on the surface of the L-Standard piston. This figure shows that intensive scratches existed in parallel arrangement on the piston leather cup surface, enabling high-pressure mud to move along the scratches from one end of the piston to the other easily, which accelerated the abrasive wear failure with the abrasive particles of the piston. Figures 4(b), 4(b′), 4(c), 4(c′), 4(d), and 4(d′) show the wear patterns of the leather cup surfaces of L-D1, L-D2, and L-D3 pistons, respectively. Figures 4(b), 4(b′), 4(c), 4(c′), 4(d), and 4(d′) show that the scratches on the leather cup surface became shallower and sparser and the surface wear patterns improved more obviously as the dimple diameter increased. If the piston leather cup surface strength was not affected to an extent as the dimple diameter increased, the reduced wear zone near the dimple would become greater and greater, indicating that the existence of dimples changed the lubricating status of the leather cup surface, their influence on nearby dimpled parts was more obvious, and they played active roles in improving the service life of the piston.

Figure 5 displays the wear patterns of the leather cup root parts of the L-D4 and L-D2 test pistons. The wear patterns of the nylon root parts of the L-D4 pistons are fewer than those of the L-D2 pistons, as shown in Figure 5. When the leather cup squeezed out high-pressure mud as driven by the piston steel core, it experienced radial squeezing while experiencing axial wear. Therefore, the area with the most serious wear was the piston leather cup root part, and the friction force at the leather cup root was much greater than that at the other areas. The rapid wear at the root decreased the piston load-carrying capacity and then affected the service life of piston. The dimples at the piston leather cup root could reduce the wear of the piston leather cup root and improve the service life of piston.

Figure 6 shows the surface wear patterns of the L-S1 and L-S2 test pistons. In Figures 6(a) and 6(a′), the scratches on the piston leather cup surface became sparse and shallow in the dimpled area. Figures 6(b) and 6(b′) show that the wear was slight in the area close to the dimples. The farther the scratches were from the dimpled area, the denser and deeper the scratches would be. The L-S1 piston had a small dimple central included angle, which was arranged more closely on the piston surface. The lubricating effects of oil storage in each row of dimples were overlaid very well, which was equivalent to amplifying the effect of each row of dimples in Figure 6(b), making the wear on the whole piston leather cup surface slight, preventing the entry of high-pressure mud into the frictional interface, and lengthening the service life of piston.

During the operation of the mud pump piston, the outside surface of the piston leather cup comes in contact with the inner wall of the cylinder liner and simultaneously moves to push the mud. The lip part of the piston leather cup mainly participated in the piston wear and exerted a sealing effect, while the piston root part mainly exerted centralizing and transitional effects. In the mud discharge stroke, the lip part of the piston experienced a “centripetal effect,” and a gap was generated between the lip part and the cylinder liner. The greater the contact pressure between the lip part and cylinder liner of the piston was, the smaller the gap was, and the entry of high-pressure mud into the contact surface between the piston and cylinder liner was more difficult. The piston root easily experienced squeezing under high pressure, and the smaller the equivalent stress caused by the piston root was, the more difficult the squeezing to occur. Hence, the contact pressure at the lip part of the piston and the equivalent stress at the root were analyzed, and they would provide a theoretical basis for the piston wear-resisting mechanism. The ANSYS Workbench module was used to perform a comparative analysis between the contact pressure at the lip part and the equivalent stress at the root of the three kinds of pistons (i.e., L-Standard piston, L-S1 piston, and L-D1 piston). The service life of the L-S1 piston exhibited the best improvement effect, whereas that of the L-D1 piston demonstrated the worst improvement effect. The piston adopted a 1 mm hexahedral grid, and the grid nodes and elements are as shown in Table 4.

We could obtain the contact pressure nephograms of the three pistons by analyzing the contact pressure of the lip parts of the L-Standard piston and two dimpled pistons, as shown in Figure 8.

An equivalent stress analysis of the root parts of the L-Standard piston and two dimpled pistons was conducted to obtain the equivalent stress nephograms of the three pistons, as shown in Figure 9.

The lubricating oil on the mud pump piston surface could reduce the wear of piston and cylinder liner and improve the service life of pistons with the reciprocating movement. The lubricating oil would eventually run off and lose lubricating effect, which would result in piston wear. The finite element fluid dynamics software CFX was used to establish the fluid domain model of the dimpled and L-Standard pistons and analyze the lubricating state on the piston surface. The piston surface streamlines are shown in Figure 10. This figure shows that the lubricating fluid did not experience truncation or backflow phenomenon when passing the surface of the L-Standard piston. When the lubricating fluid flowed through the surface of the dimpled piston, it presented a noncontinuous process. Its flow velocity at the dimpled structure slowed down obviously because it was blocked by the dimpled structure.

When the piston moved in the cylinder liner, a small quantity of solid particles in mud entered gap of piston and cylinder liner and participated in abrasion. The dimpled structure on the piston surface could store some abrasive particles (as shown in Figure 6(a′)) during the piston wear process to prevent these particles from scratching the piston and cylinder liner and generating gullies, thus avoiding secondary damage to the piston and cylinder liner and improving the piston service life.

This paper presented a dimpled-shape mud pump piston; that is, the piston leather cup surface had a dimpled array morphology in regular arrangement. The experimental results can provide the basic data for design engineering of the mud pump piston with a long service life. The comparative analyses of service life and wear patterns for dimpled mud pump pistons and L-Standard pistons were conducted. The main results and conclusions were summarized as follows:(1)The service life of the mud pump piston with dimpled morphology on the surface improved in comparison with that of the L-Standard piston, and the service life increase percentages were from 4.57% to 92.06%.(2)The piston service life would increase with the dimple diameter under the same dimpled arrangement pattern, and the maximum increase in the value of service life was 60.65%.(3)The service life of the piston with dimples increased by 7.94% in comparison with that with none.(4)Under the same dimpled arrangement patterns and area densities, the tighter and closer the dimples were arranged on the piston surface, the longer the service life of piston was, and the maximum increase in the value of service life was 92.06%.(5)Under the same wear time, the wear of the dimpled piston slightly decreased in comparison with that of the L-Standard piston, and the minimum value of wear mass percentage was 3.83%.(6)The dimpled shape could not only change the stress state of the piston structure, improve piston wear resistance, and reduce root squeezing, but also increase oil storage space, improve lubricating conditions, and enable the accommodation of some abrasive particles. Furthermore, the dimpled shape was the key factor for the service life improvement of the mud pump piston.