mud pump stroke free sample

Rig pump output, normally in volume per stroke, of mud pumps on the rig is  one of important figures that we really need to know because we will use pump out put figures to calculate many parameters such as bottom up strokes,  wash out depth, tracking drilling fluid, etc. In this post, you will learn how to calculate pump out put for triplex pump and duplex pump in bothOilfield and Metric Unit.

The 2,200-hp mud pump for offshore applications is a single-acting reciprocating triplex mud pump designed for high fluid flow rates, even at low operating speeds, and with a long stroke design. These features reduce the number of load reversals in critical components and increase the life of fluid end parts.

The pump’s critical components are strategically placed to make maintenance and inspection far easier and safer. The two-piece, quick-release piston rod lets you remove the piston without disturbing the liner, minimizing downtime when you’re replacing fluid parts.

Explore a wide variety of mud pump stroke counter on Alibaba.com and enjoy exquisite deals. The machines help maintain drilling mud circulation throughout the project. There are many models and brands available, each with outstanding value. These mud pump stroke counter are efficient, durable, and completely waterproof. They are designed to lift water and mud with efficiency without using much energy or taking a lot of space.

The primary advantage of these mud pump stroke counter is that they can raise water from greater depths. With the fast-changing technology, purchase machines that come with the best technology for optimum results. They should be well adapted to the overall configuration of the installation to perform various operations. Hence, quality products are needed for more efficiency and enjoyment of the machines" full life expectancy.

Alibaba.com offers a wide selection of products with innovative features. The products are designed for a wide range of flow rates that differ by brand. They provide cost-effective options catering to different consumer needs. When choosing the right mud pump stroke counter for the drilling project, consider factors such as size, shape, and machine cost. More powerful tools are needed when dealing with large projects such as agriculture or irrigation.

Alibaba.com provides a wide range of mud pump stroke counter to suit different tastes and budgets. The site has a large assortment of products from major suppliers on the market. The products are made of durable materials to avoid corrosion and premature wear during operations. The range of products and brands on the site assures quality and good value for money.

NOV 12-P-160 Mud Pump is rated at 1600 input horsepower (1193 kw) at 120 strokes per minute, with a 12-inch (304.8 mm) stroke. Multiple liner sizes allow pressures and volumes to handle circulation requirements in deep drilling applications.

Flexibility: Compact engineering provides higher efficiency in less space. The NOV 12-P-160 Triplex Mud Pump light weight and flexible design make it easily adaptable to a variety of rig configurations. This provides flexibility as drilling requirements and conditions change.

Fluid End Modules: NOV offers a choice of fluid end modules and valve covers for every P Series pump model to select the fluid end module that exactly matches drilling requirements. All pump models can be equipped with either the standard or premium forged, two-piece interchangeable fluid modules

Our pump stroke counter systems (CPS101 Series) measure the stroke rate and number of strokes on mud pumps. The oilfield pump stroke system is user-friendly and reliable and is configurable to measure up to three mud pumps at once. Our digital pump stroke counter systems are manufactured here in the U.S. by Crown Oilfield Instrumentation, and Crown’s Pump Stroke Counter provides easy monitoring of strokes per minute on multiple mud pumps. Each mud pumps’s stroke rate can be selected individually and the display is updated regularly for accurate monitoring. LCD displays indicate both pumps strokes per minute and the total number of strokes. Located at the bottom of the panel, push buttons provide easy operation and reseting of each pump. When you need to accurately monitor and maintain the amount of mud being pumped, you can trust Crown’s oilfield stroke counters.

Kverneland, Hege, Kyllingstad, Åge, and Magne Moe. "Development and Performance Testing of the Hex Mud Pump." Paper presented at the SPE/IADC Drilling Conference, Amsterdam, Netherlands, February 2003. doi: https://doi.org/10.2118/79831-MS

As usual, winter — or the slow season — is the time most drillers take the time to maintain their equipment in order to get ready for the peak season. One of the main parts that usually needs attention is the mud pump. Sometimes, it is just a set of swabs to bring it up to snuff, but often, tearing it down and inspecting the parts may reveal that other things need attention. For instance, liners. I can usually run three sets of swabs before it is time to change the liner. New liners and swabs last a good long time. The second set of swabs lasts less, and by the time you put in your third set of swabs, it’s time to order new liners. Probably rods too. It’s not always necessary to change pistons when you change swabs. Sometimes just the rubber needs to be changed, saving money. How do you tell? There is a small groove around the outside of the piston. As it wears, the groove will disappear and it’s time for a new piston.

The wear groove on a piston can be a good indicator of the general health of your pump. If the wear is pretty even all around, chances are the pump is in pretty good shape. But if you see wear on one side only, that is a clue to dig deeper. Uneven wear is a sign that the rods are not stroking at the exact angle that they were designed to, which is parallel to the liner. So, it’s time to look at the gear end. Or as some folks call it, “the expensive end.”

The wear groove on a piston can be a good indicator of the general health of your pump. If the wear is pretty even all around, chances are the pump is in pretty good shape. But if you see wear on one side only, that is a clue to dig deeper.

After you get the cover off the gear end, the first thing to look at will be the oil. It needs to be fairly clean, with no drill mud in it. Also look for metal. Some brass is to be expected, but if you put a magnet in the oil and come back later and it has more than a little metal on it, it gets more serious. The brass in the big end of the connecting rod is a wearable part. It is made to be replaced at intervals — usually years. The most common source of metal is from the bull and pinion gears. They transmit the power to the mud. If you look at the pinion gear closely, you will find that it wears faster than the bull gear. This is for two reasons. First, it is at the top of the pump and may not receive adequate lubrication. The second reason is wear. All the teeth on both the bull and pinion gears receive the same amount of wear, but the bull gear has many more teeth to spread the wear. That is why, with a well maintained pump, the bull gear will outlast the pinion gear three, four or even five times. Pinion gears aren’t too expensive and are fairly easy to change.

This process is fairly straightforward machine work, but over the years, I have discovered a trick that will bring a rebuild up to “better than new.” When you tear a pump down, did you ever notice that there is about 1-inch of liner on each end that has no wear? This is because the swab never gets to it. If it has wear closer to one end than the other, your rods are out of adjustment. The trick is to offset grind the journals. I usually offset mine about ¼-inch. This gives me a ½-inch increase in the stroke without weakening the gear end. This turns a 5x6 pump into a 5½x6 pump. More fluid equals better holes. I adjust the rods to the right length to keep from running out the end of the liner, and enjoy the benefits.

Other than age, the problem I have seen with journal wear is improper lubrication. Smaller pumps rely on splash lubrication. This means that as the crank strokes, the rods pick up oil and it lubricates the crank journals. If your gear end is full of drill mud due to bad packing, it’s going to eat your pump. If the oil is clean, but still shows crank wear, you need to look at the oil you are using.

Oil that is too thick will not be very well picked up and won’t find its way into the oil holes in the brass to lubricate the journals. I’ve seen drillers that, when their pump starts knocking, they switch to a heavier weight oil. This actually makes the problem worse. In my experience, factory specified gear end oil is designed for warmer climates. As you move north, it needs to be lighter to do its job. Several drillers I know in the Northern Tier and Canada run 30 weight in their pumps. In Georgia, I run 40W90. Seems to work well.

The joints between drywall sheets are typically filled and sealed with strips of paper or fiberglass mat and drywall joint compound, also called “joint compound”, “drywall mud”, or just “mud”. Joint compound may be made, for example, of water, limestone, expanded perlite, ethylene-vinyl acetate polymer and attapulgite. Joint compound is applied as a viscous fluid that is thick enough to maintain its shape while it hardens. In addition to forming joints, drywall mud is used to cover nail or screw heads, form a smooth or flat surface, and provide a texture over the surface. Paint or wall paper is typically applied over the drywall and joint compound.

Workers often specialize in the installation of drywall, and in large projects different crews install the drywall panels (drywall hangers) from those who finish the joints and apply the joint compound (tapers or mudmen). Workers who specialize in drywall installation often use specialized tools to increase their productivity including flat boxes that are tools used to hold joint compound and apply it to drywall joints. Joint compound is often mixed (e.g., with water) or stored in buckets, and drywall mud pumps have been used to pump the mud from the buckets into flat boxes or other tools or containers.

U.S. patent application Ser. No. 11/292,238, publication 2007/0122301 (also by Werner Schlecht) describes a drywall mud pump. However, it was found that in operation pumping drywall joint compound that friction developed within the pump making it difficult to use. Thus, needs or potential for benefit exist for drywall mud pumps that have less internal friction. In addition, needs and potential for benefit exist for drywall mud pumps that are inexpensive to manufacture, reliable, easy to use, that have a long life, that are easy to service and clean, and that are simple in operation so that typical operators can effectively maintain them. Room for improvement exists over the prior art in these and other areas that may be apparent to a person of ordinary skill in the art having studied this document.

This invention provides, among other things, certain drywall mud (drywall joint compound) pumps with particular features or capabilities. Various embodiments provide, as objects or benefits, for example, that they have less internal friction than certain prior art pumps. In addition, particular embodiments provide, for instance, as objects or benefits, drywall mud pumps that are inexpensive to manufacture, reliable, easy to use, that have a long life, that are easy to service and clean, that are simple in operation, or a combination thereof. Other benefits of certain embodiments may be apparent to a person of ordinary skill in the art.

In specific embodiments, this invention provides certain drywall mud pumps that include a main cylinder and a rod having two ends, a first end and a second end. In many embodiments, when the drywall mud pump is assembled, the second end of the rod is located within the main cylinder, for example. Various embodiments also include a piston which, when the drywall mud pump is assembled, is also located within the main cylinder and is attached to the second end of the rod. In some embodiments, there is a connection structure between the piston and the second end of the rod, which is configured to allow the second end of the rod to move relative to the piston in a direction that is substantially perpendicular to the axis of the rod. A number of embodiments include a means for allowing the second end of the rod to move laterally relative to the piston within the main cylinder. Further, in some embodiments the piston specifically includes an elongated hole that receives the second end of the rod, and the elongated hole allows the second end of the rod to move laterally relative to the piston.

Various such embodiments further include a pump head, which may have an output aperture, and when the drywall mud pump is assembled, the pump head may be connected to the main cylinder and the rod may pass through the pump head. In some embodiments, the drywall mud pump further includes a handle and a linkage, and when the drywall mud pump is assembled, the handle may be pivotably connected to the first end of the rod, and the linkage may be pivotably connected to the pump head and pivotably connected to the handle, as examples. Moreover, some embodiments may include (e.g., in the pump head) a means for guiding the rod, a means for allowing the rod to pivot as the second end of the rod moves laterally relative to the piston, or both. Further, particular embodiments include a guide having a hole through which the rod slidably passes. Some embodiments include just one guide in the pump head, which may serve as both a guide and as a pivot point for the rod, and in some embodiments, the guide may be shortened to provide for pivoting.

In a number of embodiments, the piston includes an elastomeric piston cup having a first hole, which may be elongated, a top rigid support having a second elongated hole, a bottom rigid support having a third elongated hole, and a flapper having a fourth elongated hole. In some embodiments, when the drywall mud pump is assembled, the second end of the rod passes through each of the first, second, third, and fourth holes, for example. Further, certain embodiments include a means for preventing the piston from rotating about the rod. In some embodiments, as an example, the second end of the rod has a flattened portion, at least the second and third elongated holes are substantially the same size and have substantially the same shape, and, when the drywall mud pump is assembled, are held in a particular orientation by the flattened portion of the second end of the rod.

Even further, in some embodiments, when the drywall mud pump is assembled, the second end of the rod is attached to the piston with a nut (e.g., a lock nut), an elongated washer, or both. Moreover, in some embodiments, the piston cup, the top rigid support, and the bottom rigid support each have at least one passageway therethrough for passage of the drywall mud, and when the drywall mud pump is assembled, the flapper covers the (at least one) passageway substantially blocking passage of the drywall mud when the piston is moving in the main cylinder toward the pump head.

In various embodiments, the piston cup, the top rigid support, and the bottom rigid support each have multiple passageways therethrough for passage of the drywall mud, and the multiple passageways substantially surround the first, second, and third elongated holes. In addition, in some such embodiments, a plurality of the multiple passageways for passage of the drywall mud have at least one curved side and at least one straight side. Additionally, in particular embodiments wherein an elongated washer is provided, when the drywall mud pump is assembled, the washer substantially blocks the elongated hole in the piston to prevent drywall mud from passing through the elongated hole in the piston. In a number of such embodiments, the drywall mud pump may also include a means for controlling the rotational position of the washer.

Further, in some embodiments, the second end of the rod includes a first reduced diameter flattened section and a second reduced diameter flattened section. In some such embodiments, for example, the second reduced diameter flattened section has a smaller diameter, thickness between flats, or both, than the first reduced diameter flattened section. Further, in some embodiments, the second end of the rod also includes a threaded section. Further still, in some embodiments, when the drywall mud pump is assembled, the second end of the rod passes through each of the first, second, third, and fourth elongated holes such that the fourth elongated hole is located at the first reduced diameter flattened section, and the first, second and third elongated holes are located at the second reduced diameter flattened section. In addition, various other embodiments of the invention are also described herein.

FIG. 7 is an isometric exploded view of the piston, rod, and pump head of the example of a mud pump of the previous figures, except that the piston in FIG. 7 is not shown exploded;

FIG. 1 illustrates an example of an assembled drywall mud pump, pump 10. Parts and features that are visible from the outside in this view include output aperture 11 in pump head 14 where drywall mud emerges from pump 10 when handle 12 is moved, for example, by an operator of drywall mud pump 10. In some embodiments, a detachable high filler (not shown) may attach to aperture 11 (e.g., with the nuts 11nshown) and may extend the location where the mud emerges to a higher elevation to enhance ergonomics. FIG. 2 is an exploded view of the same embodiment of drywall mud pump 10 shown in FIG. 1.

In the embodiment illustrated, rod 13 passes through pump head 14 (visible in FIG. 1 through aperture 11) into main cylinder 15. Pump head 14 is mounted on or connected to main cylinder 15, in this embodiment, with clips 25. Also in this embodiment, handle 12 is pivotably connected to the top or first end 21 of rod 13 with pin 23, and linkage 16 is pivotably connected at the top (of linkage 16) to handle 12 and at the bottom (of handle 16) to pump head 14 with bolts 26.

Other visible parts of pump 10 include foot plate 18, which is connected to pump head 14 with bolts 28, in this embodiment, and foot valve 19, which is connected to the bottom end of cylinder 15 with pin 29. When in use, main cylinder 15 may extend into a bucket of drywall joint compound or mud while foot plate 18 may extend outside of the bucket to the floor. The operator may place his foot on foot plate 18 to steady pump 10 while moving handle 12. Foot valve 19, in the bottom of the bucket, may form or include a check valve that may allow mud to flow upward into cylinder 15, but may substantially prevent mud from flowing downward out of cylinder 15 through foot valve 19. Rod 13 also passes through shortened guide 17, in this embodiment, and guide 17 is attached to pump head 14 with bolts 27. Thus, guide 17 is easily removable and replaceable.

FIG. 2 also introduces piston 20, which, in this embodiment, includes several different components that will be discussed in more detail with reference to other figures. In this embodiment, when drywall mud pump 10 is assembled, piston 20 is located within main cylinder 15 and is attached to the bottom or second end 22 of rod 13. In addition, when drywall mud pump 10 is assembled, second end 22 of rod 13 is also located within main cylinder 15. When an operator pushes handle 12 down, piston 20 goes up toward pump head 14, pushing drywall mud that is in cylinder 15 out through aperture 11. During this process, a vacuum is created below piston 20, which draws more drywall mud into cylinder 15 through foot valve 19. When the operator pulls handle 12 up, piston 20 goes down, away from pump head 14, foot valve 19 prevents the drywall mud below piston 20 from exiting cylinder 15 through the bottom, and drywall mud flows through piston 20, as will be described in more detail below.

During the operation of mud pump 10, horizontal or lateral forces are exerted on rod 13. Even if the operator only exerts vertical forces on handle 12, since linkage 16 is not vertical during most of the stroke of piston 20, linkage 16 exerts lateral forces on handle 12, which are carried by handle 12 to rod 13. These horizontal or lateral forces on rod 13 are believed to cause increased friction or binding within prior art drywall mud pumps. In a number of embodiments, drywall mud pump 10, and various other drywall mud pumps in accordance with this invention, allow rod 13 to move laterally without binding (or with reduced binding) and in a manner that reduces friction (e.g., within mud pump 10). In different embodiments, such a reduction in friction makes the drywall mud pump (e.g., 10) easier to use. In addition, in many embodiments, reduced friction reduces wear, thus increasing pump life, maintaining a level of pump performance for a longer time, reducing the need for replacement of parts, reducing the need for servicing of the pump, or the like.

In a number of embodiments, piston cup 44 may be an elastomeric material such as rubber or a synthetic equivalent thereof. Other components shown in FIGS. 3 and 4 may be metal, such as steel, stainless steel, brass, bronze, aluminum, or the like, or may be made of a plastic, a polymer, or nylon, for example. In the embodiment illustrated, piston cup 44 has an outside diameter that is slightly larger than the inside diameter of main cylinder 15. Thus, an interference fit may exist between piston cup 44 and main cylinder 15, and when piston 20 is inside main cylinder 15 (e.g., when drywall mud pump 10 is assembled), the outside diameter of piston cup 44 may contact the inside surface of main cylinder 15.

Flapper 46, in this embodiment, has an outside diameter that is less than the outside diameter of piston cup 44, less than the inside diameter of main cylinder 15, and may be less than the outside diameter of bottom wiper support 43, top wiper support 45, or both. In this embodiment, Flapper 46 has a diameter that is sufficiently small to allow drywall mud to flow between flapper 46 and the inside surface of main cylinder 15, for example, when piston 20 is traveling downward (e.g., away from pump head 14). In the embodiment illustrated, flapper 46 is rigid. In other embodiments, flapper 46 may be flexible. In some embodiments, flapper 46 (or an alternative flapper) may bend or pivot out of the way of the flow of drywall mud when piston 20 is traveling downward, for example. In some embodiments, a flapper or component analogous to flapper 46 may be made of two or more pieces, which may be different materials and may have different stiffnesses.

In the embodiment illustrated, piston cup 44 of piston 20 has a first elongated hole 44h, top support 45 has a second elongated hole 45h, bottom support 43 has a third elongated hole 43h, and flapper 46 has a fourth elongated hole 46h. In the embodiment shown, when drywall mud pump 10 is assembled, second end 22 of rod 13 passes through each of the first, second, third, and fourth elongated holes (i.e., 43h, 44h, 45h, and 46h). Further, the embodiment illustrated includes a means for preventing piston 20 from rotating about rod 13. Specifically, in the embodiment illustrated, second end 22 of rod 13 has first and second flattened portions 49 and 48, which, in this embodiment, each have a reduced diameter from the remainder of rod 13. In this embodiment, the second and third elongated holes (i.e., holes 45hand 43hin top and bottom supports 45 and 43) are substantially the same size and have substantially same shape, and, when drywall mud pump 10 is assembled, are held in a particular orientation by second flattened portion 48 of second end 22 of rod 13.

In the embodiment illustrated, second reduced diameter flattened section 48 has a smaller diameter and thickness between flats than first reduced diameter flattened section 49. Other embodiments may have different sections that just have different diameters or different thicknesses between flats. Further, in the embodiment shown, second end 22 of rod 13 also includes threaded section 47, which in this embodiment, receives nut 41. Further still, when drywall mud pump 10 is assembled, second end 22 of rod 13 passes through each of first, second, third, and fourth elongated holes 43h-46hsuch that fourth elongated hole 46his located at first reduced diameter flattened section 49, and first, second and third elongated holes 43h-45hare located at second reduced diameter flattened section 48.

In the embodiment shown, flattened portion 49 has a sufficient dimension in the axial direction (i.e., of the longitudinal axis of rod 13) to allow flapper 46 to move away from top support 45 when piston 20 is traveling downward away from pump head 14. This allows room for the drywall mud to flow outward between flapper 46 and top support 45 before flowing around the outside of flapper 46. When piston 20 travels in upward, toward pump head 14, flapper 46 moves in the axial direction to the other end of flattened portion 49 until flapper 46 makes contact with top support 45.

As used herein, a means for allowing an end of a rod to move laterally relative to a piston does not include motion resulting from prior art magnitude clearance between the rod and the piston in a drywall mud pump, movement resulting from deformation of an elastomeric piston cup, or deformation of the rod or other components resulting from stress imposed thereon. Rather, a means for allowing an end of a rod to move laterally relative to a piston requires a structure that provides for substantially more lateral movement of the rod under substantially less force than prior art mud pump technology provided. In this context, as used herein, “substantially” means by a factor of at least two.

In different embodiments, the second end 22 of rod 13 may be able to move laterally relative to piston 20 by at least or about 1/16, ⅛, 3/16, ¼, 5/16, ⅜, 7/16, ½, 9/16, ⅝, ¼, ⅞, 1, 1⅛, 1¼, or 1½, inch, or 2 inches, for example, under lateral forces normally present within such a drywall mud pump. In the embodiment illustrated, the elongated hole (e.g., 43h) in piston 20 is centered within piston 20. But in other embodiments, the elongated hole may extend from the center of piston 20 in one direction, or may extend farther on one side of center than the other, as examples.

Bottom support 43 also includes multiple passageways 53, 54, 55, and 56 therethrough for passage of drywall mud. These passageways 53, 54, 55, and 56 substantially surround (third) elongated hole 43h. As shown in FIG. 4, in the embodiment illustrated, corresponding passageways having substantially the same shape extend through piston cup 44 and top support 45 and substantially surround (first and second) holes 44hand 45h, as well. Drywall mud flows through these passageways (e.g., 53-56), between top support 45 and flapper 46, and around the outside of flapper 46 (i.e., between flapper 46 and the inside of main cylinder 15) when piston 20 is moving downward (i.e., away from pump head 14).

Still referring to FIG. 5, in the embodiment illustrated, all four of the multiple passageways 53, 54, 55, and 56 for passage of drywall mud have at least one curved side 57 and at least one straight side 58, as labeled, for example, for passageway 56. In the embodiment illustrated, the shape of passageways 53, 54, 55, and 56 provides for essentially as much area for the flow of drywall mud therethrough as possible, while maintaining adequate structural strength of the components (e.g., bottom support 43, piston cup 44, etc.).

As mentioned, when piston 20 is traveling upward (i.e., toward pump head 14) in cylinder 15, flapper 46 makes contact with top support 45, blocking or substantially blocking passageways 53, 54, 55, and 56, thus preventing significant quantities of the drywall mud from flowing back through passageways 53, 54, 55, and 56. As used herein, in the context of blocking the flow of drywall mud, “substantially blocking” means blocking more than 90 percent of the cross sectional area (e.g., of passageways 53, 54, 55, and 56), and “blocking” (i.e., without being preceded by “substantially”) means blocking more than 99 percent of the cross sectional area (e.g., of passageways 53, 54, 55, and 56). Blocking or substantially blocking of passageways 53, 54, 55, and 56, in the embodiment illustrated, causes the drywall mud within cylinder 15 to exit through pump head 14 and orifice 11 when piston 20 travels upward (i.e., toward pump head 14).

Further, as shown for example in FIG. 3, in the embodiment illustrated, when drywall mud pump 10 is assembled, washer 42 blocks or substantially blocks the elongated hole (e.g., 43h, 44h, 45h, and 46h) in piston 20 to prevent drywall mud from passing through the elongated hole in piston 20 (e.g., when piston 20 is moving upward toward pump head 14). In a number of such embodiments, the drywall mud pump (e.g., 10), piston (e.g., 20), or rod (e.g., 13) may also include a means for controlling the orientation or rotational position (i.e., about the longitudinal axis of rod 13) of the washer (e.g., 42). This may facilitate washer 42 blocking or substantially blocking the elongated hole (e.g., 43h).

FIG. 6 illustrates piston 20, rod 13, pump head 14, and shortened guide 17, all assembled. In this view, flapper 46 is shown against upper guide 45 (not visible) blocking or substantially blocking passageways 53, 54, 55, and 56, as would be the case when piston 20 is moving toward pump head 14. FIG. 7 shows these same components of drywall mud pump 10 in an exploded view, except that piston 20 is not separated into components or separated from rod 13. FIG. 7 shows, among other things, that below guide 17 is a wiper or rod seal 77, which may be made of an elastomeric material or synthetic rubber, for example, and may serve to prevent or substantially prevent drywall mud from within main cylinder or pump head 14 from traveling up along rod 13 through guide 17. Rod seal 77 may have a U-shaped cross section, for example, with the opening of the U pointed downward (i.e., toward piston 20). In other embodiments, rod seal 77 may have a cross section that is square, rectangular, triangular, trapezoidal, a parallelogram, or round, as examples, and may be solid or hollow.

FIGS. 8 and 9 illustrate more detail of the example of guide 17 of the embodiment illustrated. Guide 17, in this embodiment, includes hole 80hthrough which rod 13 passes when drywall mud pump 10 is assembled. Some embodiments may include (e.g., in pump head 14) a means for guiding rod 13, a means for allowing rod 13 to pivot (e.g., without binding) as second end 22 of rod 13 moves laterally relative to piston 20, or both. In the embodiment illustrated, guide 17 is a shortened guide, and rod 13 slidably passes through hole 80hwhen pump 10 is assembled. Prior art guides for drywall mud pumps typically have a gland nut with a dimension 90t(shown in FIG. 9) in the direction of the longitudinal axis of rod 13 that is ¾ inch or more. In the embodiment illustrated, guide 17 has a dimension 90tof 0.300 inches. Other embodiments may have a dimension 90tthat is more than ⅛, 3/16, or ¼ inch, and less than ½, ⅜ or 5/16 inch, or the like, as examples. As used herein, a “shortened guide” has a dimension 90tthat is less than ½ inch.

In some embodiments, guide 17 serves both as a guide and as a pivot point for rod 13. In some such embodiments, the outside diameter of rod 13 and the inside diameter of hole 80hare selected to provide sufficient clearance between rod 13 and hole 80hto allow second end 22 of rod 13 to move laterally over, for instance, the full range of the elongated hole (e.g., 43h, 44h, 45h, 46h, or a combination thereof) in piston 20 without causing binding between rod 13 and hole 80h, for example, within guide 17. Further, in the prior art, upper and lower guides were used at the top and bottom of the pump head (e.g., otherwise similar to pump head 14). This provided little opportunity for the rod (e.g., similar to rod 13) to pivot in the pump head, and (as used herein) no means for allowing the rod to pivot as the second end of the rod moves laterally relative to the piston. In the embodiment shown, only one (i.e., a single) guide (17) is provided, and guide 17 is shortened, which (as used herein), if sized or shaped in certain ways, may provide a means for allowing rod 13 to pivot without binding as second end 22 of rod 13 moves laterally relative to piston 20.

In some embodiments, hole 80his manufactured as a right circular cylinder (e.g., a drilled hole), but quickly “wears in” when in use, to a shape that is elongated, for instance, with the most pronounced elongation at the top or bottom surface (or both) of guide 17. In some such embodiments, guide 17 is made of a relatively soft material, such as brass, and rod 13 is made of a harder material, such as stainless steel, which may be grade 420 stainless steel, and may be hardened to 35 Rockwell C (HRC), for example. In particular embodiments, rod 13 has an outside diameter of 0.626±0.005 inches, and hole 80hin guide 17 has an inside diameter of 0.640±0.003 inches, for instance. In various such embodiments, friction in the operation of pump 10 may be greater when pump 10 is new, but may decrease once guide 17 wears in and binding between guide 17 and rod 13 declines or ceases. Such a shortened guide 17 that is configured to “wear in” to a shape that does not bind against rod 13, as used herein, is another example of a means for allowing rod 13 to pivot as second end 22 of rod 13 moves laterally relative to piston 20.

In the embodiment illustrated, once guide 17 wears in, and binding between guide 17 and rod 13 declines or ceases, the rate at which guide 17 wears may decrease substantially. However, in cases of frequent use of pump 10, guide 17 may continue to wear over time with continued use. At some point, guide 17 may be replaced. In the embodiment shown, guide 17 and seal 77 are easily replaceable by removing pin 23 and bolts 27.

Triplex mud pumps pump drilling mud during well operations. An example of a typical triplex mud pump 10 shown in FIG. 1A has a power assembly 12, a crosshead assembly 14, and a fluid assembly 16. Electric motors (not shown) connect to a pinion shaft 30 that drives the power assembly 12. The crosshead assembly 14 converts the rotational movement of the power assembly 12 into reciprocating movement to actuate internal pistons or plungers of the fluid assembly 16. Being triplex, the pump"s fluid assembly 16 has three internal pistons to pump the mud.

As shown in FIG. 1B, the pump"s power assembly 14 has a crankshaft 20 supported at its ends by double roller bearings 22. Positioned along its intermediate extent, the crankshaft 20 has three eccentric sheaves 24-1 . . . 24-3, and three connecting rods 40 mount onto these sheaves 24 with cylindrical roller bearings 26. These connecting rods 40 connect by extension rods (not shown) and the crosshead assembly (14) to the pistons of the pump"s fluid assembly 16.

In addition to the sheaves, the crankshaft 20 also has a bull gear 28 positioned between the second and third sheaves 24-2 and 24-3. The bull gear 28 interfaces with the pinion shaft (30) and drives the crankshaft 20"s rotation. As shown particularly in FIG. 1C, the pinion shaft 30 also mounts in the power assembly 14 with roller bearings 32 supporting its ends. When electric motors couple to the pinion shaft"s ends 34 and rotate the pinion shaft 30, a pinion gear 38 interfacing with the crankshaft"s bull gear 28 drives the crankshaft (20), thereby operating the pistons of the pump"s fluid assembly 16.

When used to pump mud, the triplex mud pump 10 produces flow that varies by approximately 23%. For example, the pump 10 produces a maximum flow level of about 106% during certain crankshaft angles and produces a minimum flow level of 83% during other crankshaft angles, resulting in a total flow variation of 23% as the pump"s pistons are moved in differing exhaust strokes during the crankshaft"s rotation. Because the total flow varies, the pump 10 tends to produce undesirable pressure changes or “noise” in the pumped mud. In turn, this noise interferes with downhole telemetry and other techniques used during measurement-while-drilling (MWD) and logging-while-drilling (LWD) operations.

In contrast to mud pumps, well-service pumps (WSP) are also used during well operations. A well service pump is used to pump fluid at higher pressures than those used to pump mud. Therefore, the well service pumps are typically used to pump high pressure fluid into a well during frac operations or the like. An example of a well-service pump 50 is shown in FIG. 2. Here, the well service pump 50 is a quintuplex well service pump, although triplex well service pumps are also used. The pump 50 has a power assembly 52, a crosshead assembly 54, and a fluid assembly 56. A gear reducer 53 on one side of the pump 50 connects a drive (not shown) to the power assembly 52 to drive the pump 50.

As shown in FIG. 3, the pump"s power assembly 52 has a crankshaft 60 with five crankpins 62 and an internal main bearing sheave 64. The crankpins 62 are offset from the crankshaft 60"s axis of rotation and convert the rotation of the crankshaft 60 in to a reciprocating motion for operating pistons (not shown) in the pump"s fluid assembly 56. Double roller bearings 66 support the crankshaft 60 at both ends of the power assembly 52, and an internal double roller bearing 68 supports the crankshaft 60 at its main bearing sheave 64. One end 61 of the crankshaft 60 extends outside the power assembly 52 for coupling to the gear reducer (53; FIG. 2) and other drive components.

As shown in FIG. 4A, connecting rods 70 connect from the crankpins 62 to pistons or plungers 80 via the crosshead assembly 54. FIG. 4B shows a typical connection of a connecting rod 70 to a crankpin 62 in the well service pump 50. As shown, a bearing cap 74 fits on one side of the crankpin 62 and couples to the profiled end of the connecting rod 70. To reduce friction, the connection uses a sleeve bearing 76 between the rod 70, bearing cap 74, and crankpin 62. From the crankpin 62, the connecting rod 70 connects to a crosshead 55 using a wrist pin 72 as shown in FIG. 4A. The wrist pin 72 allows the connecting rod 70 to pivot with respect to the crosshead 55, which in turn is connected to the plunger 80.

In use, an electric motor or an internal combustion engine (such as a diesel engine) drives the pump 50 by the gear reducer 53. As the crankshaft 60 turns, the crankpins 62 reciprocate the connecting rods 70. Moved by the rods 70, the crossheads 55 reciprocate inside fixed cylinders. In turn, the plunger 80 coupled to the crosshead 55 also reciprocates between suction and power strokes in the fluid assembly 56. Withdrawal of a plunger 80 during a suction stroke pulls fluid into the assembly 56 through the input valve 82 connected to an inlet hose or pipe (not shown). Subsequently pushed during the power stroke, the plunger 80 then forces the fluid under pressure out through the output valve 84 connected to an outlet hose or pipe (not shown).

In contrast to using a crankshaft for a quintuplex well-service pump that has crankpins 62 as discussed above, another type of quintuplex well-service pump uses eccentric sheaves on a direct drive crankshaft. FIG. 4C is an isolated view of such a crankshaft 90 having eccentric sheaves 92-1 . . . 92-5 for use in a quintuplex well-service pump. External main bearings (not shown) support the crankshaft 90 at its ends 96 in the well-service pumps housing (not shown). To drive the crankshaft 90, one end 91 extends beyond the pumps housing for coupling to drive components, such as a gear box. The crankshaft 90 has five eccentric sheaves 92-1 . . . 92-5 for coupling to connecting rods (not shown) with roller bearings. The crankshaft 90 also has two internal main bearing sheaves 94-1, 94-2 for internal main bearings used to support the crankshaft 90 in the pump"s housing.

In the past, quintuplex well-service pumps used for pumping frac fluid or the like have been substituted for mud pumps during drilling operations to pump mud. Unfortunately, the well-service pump has a shorter service life compared to the conventional triplex mud pumps, making use of the well-service pump as a mud pump less desirable in most situations. In addition, a quintuplex well-service pump produces a great deal of white noise that interferes with MWD and LWD operations, further making the pump"s use to pump mud less desirable in most situations. Furthermore, the well-service pump is configured for direct drive by a motor and gear box directly coupling on one end of the crankshaft. This direct coupling limits what drives can be used with the pump. Moreover, the direct drive to the crankshaft can produce various issues with noise, balance, wear, and other associated problems that make use of the well-service pump to pump mud less desirable.

One might expect to provide a quintuplex mud pump by extending the conventional arrangement of a triplex mud pump (e.g., as shown in FIG. 1B) to include components for two additional pistons or plungers. However, the actual design for a quintuplex mud pump is not as easy as extending the conventional arrangement, especially in light of the requirements for a mud pump"s operation such as service life, noise levels, crankshaft deflection, balance, and other considerations. As a result, acceptable implementation of a quintuplex mud pump has not been achieved in the art during the long history of mud pump design.

What is needed is an efficient mud pump that has a long service life and that produces low levels of white noise during operation so as not to interfere with MWD and LWD operations while pumping mud in a well.

A quintuplex mud pump is a continuous duty, reciprocating plunger/piston pump. The mud pump has a crankshaft supported in the pump by external main bearings and uses internal gearing and a pinion shaft to drive the crankshaft. Five eccentric sheaves and two internal main bearing sheaves are provided on the crankshaft. Each of the main bearing sheaves supports the intermediate extent of crankshaft using bearings. One main bearing sheave is disposed between the second and third eccentric sheaves, while the other main bearing sheave is disposed between the third and fourth eccentric sheaves.

One or more bull gears are also provided on the crankshaft, and the pump"s pinion shaft has one or more pinion gears that interface with the one or more bull gears. If one bull gear is used, the interface between the bull and pinion gears can use herringbone or double helical gearing of opposite hand to avoid axial thrust. If two bull gears are used, the interface between the bull and pinion gears can use helical gearing with each having opposite hand to avoid axial thrust. For example, one of two bull gears can be disposed between the first and second eccentric sheaves, while the second bull gear can be disposed between fourth and fifth eccentric sheaves. These bull gears can have opposite hand. The pump"s internal gearing allows the pump to be driven conventionally and packaged in any standard mud pump packaging arrangement. Electric motors (for example, twin motors made by GE) may be used to drive the pump, although the pump"s rated input horsepower may be a factor used to determine the type of motor.

Connecting rods connect to the eccentric sheaves and use roller bearings. During rotation of the crankshaft, these connecting rods transfer the crankshaft"s rotational movement to reciprocating motion of the pistons or plungers in the pump"s fluid assembly. As such, the quintuplex mud pump uses all roller bearings to support its crankshaft and to transfer crankshaft motion to the connecting rods. In this way, the quintuplex mud pump can reduce the white noise typically produced by conventional triplex mud pumps and well service pumps that can interfere with MWD and LWD operations.

Turning to the drawings, a quintuplex mud pump 100 shown in FIGS. 5 and 6A-6B has a power assembly 110, a crosshead assembly 150, and a fluid assembly 170. Twin drives (e.g., electric motors, etc.) couple to ends of the power assembly"s pinion shaft 130 to drive the pump"s power assembly 110. As shown in FIGS. 6A-6B, internal gearing within the power assembly 110 converts the rotation of the pinion shaft 130 to rotation of a crankshaft 120. The gearing uses pinion gears 138 on the pinion shaft 130 that couple to bull gears 128 on the crankshaft 120 and transfer rotation of the pinion shaft 130 to the crankshaft 120.

For support, the crankshaft 120 has external main bearings 122 supporting its ends and two internal main bearings 127 supporting its intermediate extent in the assembly 110. As best shown in FIG. 6A, rotation of the crankshaft 120 reciprocates five independent connecting rods 140. Each of the connecting rods 140 couples to a crosshead 160 of the crosshead assembly 150. In turn, each of the crossheads 160 converts the connecting rod 40"s movement into a reciprocating movement of an intermediate pony rod 166. As it reciprocates, the pony rod 166 drives a coupled piston or plunger (not shown) in the fluid assembly 170 that pumps mud from an intake manifold 192 to an output manifold 198. Being quintuplex, the mud pump 100 has five such pistons movable in the fluid assembly 170 for pumping the mud.

The cross-section in FIG. 10A shows a crosshead 160 for the quintuplex mud pump. The end of the connecting rod 140 couples by a wrist pin 142 and bearing 144 to a crosshead body 162 that is movable in a crosshead guide 164. A pony rod 166 coupled to the crosshead body 162 extends through a stuffing box gasket 168 on a diaphragm plate 169. An end of this pony rod 166 in turn couples to additional components of the fluid assembly (170) as discussed below.

The cross-section in FIG. 10B shows portion of the fluid assembly 170 for the quintuplex mud pump. An intermediate rod 172 has a clamp 174 that couples to the pony rod (166; FIG. 10A) from the crosshead assembly 160 of FIG. 10A. The opposite end of the rod 172 couples by another clamp to a piston rod 180 having a piston head 182 on its end. Although a piston arrangement is shown, the fluid assembly 170 can use a plunger or any other equivalent arrangement so that the terms piston and plunger can be used interchangeably herein. Moved by the pony rod (166), the piston head 182 moves in a liner 184 communicating with a fluid passage 190. As the piston 182 moves, it pulls mud from a suction manifold 192 through a suction valve 194 into the passage 190 and pushes the mud in the passage 190 to a discharge manifold 198 through a discharge valve 196.

As noted previously, a triplex mud pump produces a total flow variation of about 23%. Because the present mud pump 100 is quintuplex, the pump 100 offers a lower variation in total flow, making the pump 100 better suited for pumping mud and producing less noise that can interfere with MWD and LWD operations. In particular, the quintuplex mud pump 100 can produce a total flow variation as low as about 7%. For example, the quintuplex mud pump 100 can produce a maximum flow level of about 102% during certain crankshaft angles and can produce a minimum flow level of 95% during other crankshaft angles as the pump"s five pistons move in their differing strokes during the crankshaft"s rotation. Being smoother and closer to ideal, the lower total flow variation of 7% produces less pressure changes or “noise” in the pumped mud that can interfere with MWD and LWD operations.

Although a quintuplex mud pump is described above, it will be appreciated that the teachings of the present disclosure can be applied to multiplex mud pumps having at least more than three eccentric sheaves, connecting rods, and fluid assembly pistons. Preferably, the arrangement involves an odd number of these components so such mud pumps may be septuplex, nonuplex, etc. For example, a septuplex mud pump according to the present disclosure may have seven eccentric sheaves, connecting rods, and fluid assembly pistons with at least two bull gears and at least two bearing sheaves on the crankshaft. The bull gears can be arranged between first and second eccentric sheaves and sixth and seventh eccentric sheaves on the crankshaft. The internal main bearings supporting the crankshaft can be positioned between third and fourth eccentric sheaves and the fourth and fifth eccentric sheaves on the crankshaft.