Abstract:
A system for pumping fluid (e.g., but not limited to, drilling fluid), the system having pump apparatus; including a plurality of removable pump modules; and, in certain aspects, removable valve cartridges for such modules. This abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims, 37 C.F.R. 1.72(b).

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field Of The Invention 
         [0002]    This present invention is directed to drilling wellbores in the earth, to systems for pumping drilling fluid (“mud”) for such operations, to pump modules for such systems, and methods of their use. 
         [0003]    2. Description of Related Art 
         [0004]    The prior art discloses a wide variety of drilling systems, apparatuses, and methods including, but not limited to, the disclosures in U.S. Pat. Nos. 6,944,547; 6,918,453; 6,802,378; 6,050,348; 5,465,799; 4,995,465; 4,854,397; and 3,658,138, all incorporated fully herein for all purposes. The prior art discloses a wide variety of drilling fluid pumps (“mud pumps”) used in drilling operations and pump systems; for example, and not by way of limitation, those pumps and systems disclosed in U.S. Pat. Nos. 6,257,354; 4,295,366; 4,527,959; 5,616,009; 4,242,057; 4,676,724; 5,823,093; 5,960,700; 5,059,101; 5,253,987; 6,718,955; and in U.S. application Ser. No. 10/833,921 filed Apr. 28, 2004 (all said U.S. references incorporated fully herein for all purposes). 
         [0005]    By rotating a drill bit carried at an end of a drillstring wellbores are formed in the earth. Certain drillstrings include tubulars which may be drill pipe made of jointed sections or a continuous coiled tubing and a drilling assembly that has a drill bit at its bottom end. The drilling assembly is attached to the bottom end of the tubing or drillstring. In certain systems, to drill a wellbore, the drill bit is rotated by a downhole mud motor carried by the drilling assembly and/or by rotating the drill pipe (e.g. with a rotary system, power swivel, or with a top drive system). A drilling fluid, also referred to as “mud,” is pumped under pressure from a pit or container at the surface by a pumping system at the surface. 
         [0006]    Drilling fluid or mud can serve a variety of purposes. It can provide downhole hydrostatic pressure that is greater than the formation pressure to control the pressure of fluid in the earth formation being drilled and to avoid blow outs. The mud drives a downhole drilling motor (when used) and it also provides lubrication to various elements of the drill string. Commonly used drilling fluids are either water-based or oil-based fluids. They can also contain a variety of additives which provide desired viscosity, lubricating characteristics, heat, anti-corrosion and other performance characteristics. 
         [0007]    During drilling, the mud that is pumped downhole by the mud pump system is discharged at the bottom of the drill bit and returns to the surface via the annular space between the tubulars of the drillstring and the wellbore inside (also referred to as the “annulus”). 
         [0008]    Certain prior, known mud pumps and mud pump systems have relatively complex and relatively heavy drive systems with typical connecting rods, eccentric shafts, and multiple rotating bearings, and many of these parts require constant lubrication. Certain prior “triplex” systems have a relatively large footprint. 
         [0009]    Pending U.S. patent application Ser. No. 11/796,623 filed Apr. 27, 2007, co-owned with the present invention and incorporated fully herein for all purposes, discloses systems for pumping drilling fluid which include: a pump apparatus including a pumping section and a motor section; the pumping section having at least one pump, at least one inlet, and at least one outlet, and a main pinion shaft for operating the at least one pump; motor apparatus which is at least one AC motor; and the at least one AC motor directly connected to the main pinion shaft. In particular aspects, system for pumping drilling fluid are disclosed that include a pump apparatus including a pumping section and a motor section, the pumping section having at least one pump, at least one inlet, and at least one outlet, and a main pinion shaft for operating the at least one pump, motor apparatus comprising at least one AC motor, and the at least one AC motor directly connected to the main pinion shaft. 
         [0010]    Pending U.S. patent application Ser. No. 11/414,163 filed Apr. 29, 2006, co-owned with the present invention and incorporated fully herein for all purposes, discloses drilling fluid pumping systems, also known as a mud pump systems, for pumping drilling fluid or mud used in wellbore operations in which a permanent magnet linear motor operates a pump apparatus to pump the fluid and the linear motor applies power directly. Such systems may have one, two-ten, or more mud pump apparatuses, each with a permanent magnet linear motor. In one aspect, a system is disclosed with pump apparatus with a pumping section and a motor section, the pumping section having an inlet and an outlet, the motor section having a shaft for reciprocating in and out of the pumping section to alternately suck fluid into the inlet and pump fluid out the outlet, and the motor being a permanent magnet linear motor for moving the shaft in a reciprocating motion, e.g., but not limited to, vertically or horizontally; and methods for using such a system. 
         [0011]      FIG. 1  illustrates a prior art drilling fluid pump system S with internal pumping cylinders for pumping fluid through pump V with suction and discharge valves in a removable cartridge C. A service crane r with a pedestal P rotatably mounted on a bearing assembly B of the system S has a lift apparatus L movable on a beam E for lifting and moving system parts (e.g. pump modules, piston assemblies, roller forks). Motors T rotate pinion drives I to move a drive gear that in turn drives internal piston assemblies which drive the pumps V. In one particular aspect, the system S is a HEX 150 (Trademark) or a HEX 240 (Trademark) Pump System commercially available from National Oilwell Varco (owner of the present invention). The upper portion of the system S is like the upper portion of a system according to the present invention as shown in  FIG. 3C . 
         [0012]    The system S has a discharge ring D interconnected between and in communication with all the pump systems V. In some cases, such a discharge ring requires a relatively large space, has a relatively high weight and is relatively difficult to assemble. Also, due to internal flow direction changes, such a ring can shake during operation. In certain types of systems S, seats for the pump/valve system V are installed individually, e.g. press fit in place, and, therefore are destroyed when removed, e.g. as the result of an inspection of the inner valve. A cartridge C that has been removed is disassembled to inspect various parts, including the valve seats. In certain aspects in such prior systems expensive materials (e.g. S165M stainless steel) are used for parts and areas, e.g. standard known modules, which are subjected to high stress. 
       BRIEF SUMMARY OF THE INVENTION 
       [0013]    The present invention discloses, in certain aspects, a drilling fluid pumping system, also known as a mud pump system, for pumping drilling fluid or mud used in wellbore operations. 
         [0014]    In certain embodiments of modules in systems according to the present invention, the modules are made of relatively expensive material, e.g. S165M stainless steel e.g. with a thickness of about 2.36″ (as has been done in the past with prior modules). In other aspects, modules according to the present invention are made with a relatively thicker wall thickness, e.g. at least 25% thicker, and, in certain aspects, 50% thicker, or more, e.g. also using relatively cheaper material, e.g. 8630M alloy steel. By using thicker-walled modules, deflection (“breathing”) of the module wall near seal surfaces of the valve cartridge is reduced. Such deflection is the result of fluctuating internal pressure due to pump operation and can cause the premature failure of seals. 
         [0015]    The present invention discloses, in certain aspects, a system for pumping drilling fluid, the system including a base; a plurality of pumping apparatuses connected to the base, including a first pumping apparatus, each pumping apparatus including a pumping module with a module body; pumping structure for pumping fluid to and from each module; a conduit apparatus between each pair of adjacent modules so that fluid discharged from each module is flowable to the first pumping apparatus and into the module of the first pumping apparatus for discharge; and a main outlet for receiving fluid pumped by all the pumping apparatuses. Such a system may be used to pump drilling fliud through a wellbore in the earth (as may any system according to the present invention be used). Also, any system described herein according to the present invention for pumping fluid through a wellbore may be used to pump drilling fluid above the earth. 
         [0016]    It is, therefore, an object of at least certain preferred embodiments of the present invention to provide new, useful, unique, efficient, nonobvious drilling fluid pumping systems, methods of their use, drilling systems and methods, and mud pump systems for use in drilling operations. 
         [0017]    Accordingly, the present invention includes features and advantages which are believed to enable it to advance drilling fluid pumping technology. Characteristics and advantages of the present invention described above and additional features and benefits will be readily apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments and referring to the accompanying drawings. 
         [0018]    Certain embodiments of this invention are not limited to any particular individual feature disclosed here, but include combinations of them distinguished from the prior art in their structures, functions, and/or results achieved. Features of the invention have been broadly described so that the detailed descriptions that follow may be better understood, and in order that the contributions of this invention to the arts may be better appreciated. There are, of course, additional aspects of the invention described below and which may be included in the subject matter of the claims to this invention. Those skilled in the art who have the benefit of this invention, its teachings, and suggestions will appreciate that the conceptions of this disclosure may be used as a creative basis for designing other structures, methods and systems for carrying out and practicing the present invention. The claims of this invention are to be read to include any legally equivalent devices or methods which do not depart from the spirit and scope of the present invention. 
         [0019]    What follows are some of, but not all, the objects of this invention. In addition to the specific objects stated below for at least certain preferred embodiments of the invention, there are other objects and purposes which will be readily apparent to one of skill in this art who has the benefit of this invention&#39;s teachings and disclosures. It is, therefore, an object of at least certain preferred embodiments of the present invention to provide new, useful, unique, efficient, nonobvious fluid pumping systems., methods of their use, drilling systems and methods, and mud pump systems for use in drilling operations. 
         [0020]    The present invention recognizes and addresses the problems and needs in this area and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one of skill in this art who has the benefits of this invention&#39;s realizations, teachings, disclosures, and suggestions, other purposes and advantages will be appreciated from the following description of certain preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent&#39;s object to claim this invention no matter how others may later attempt to disguise it by variations in form, changes, or additions of further improvements. 
         [0021]    The Abstract that is part hereof is to enable the U.S. Patent and Trademark Office and the public generally, and scientists, engineers, researchers, and practitioners in the art who are not familiar with patent terms or legal terms of phraseology to determine quickly from a cursory inspection or review the nature and general area of the disclosure of this invention. The Abstract is neither intended to define the invention, which is done by the claims, nor is it intended to be limiting of the scope of the invention or of the claims in any way. 
         [0022]    It will be understood that the various embodiments of the present invention may include one, some, or all of the disclosed, described, and/or enumerated improvements and/or technical advantages and/or elements in claims to this invention. 
         [0023]    Certain aspects, certain embodiments, and certain preferable features of the invention are set out herein. Any combination of aspects or features shown in any aspect or embodiment can be used except where such aspects or features are mutually exclusive. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0024]    A more particular description of embodiments of the invention briefly summarized above may be had by references to the embodiments which are shown in the drawings which form a part of this specification. These drawings illustrate certain preferred embodiments and are not to be used to improperly limit the scope of the invention which may have other equally effective or legally equivalent embodiments. 
           [0025]      FIG. 1  is a front view of a prior art pumping system. 
           [0026]      FIG. 2  is a schematic view, partially cutaway, of a system according to the present invention. 
           [0027]      FIG. 3A  is a perspective view of a system according to the present invention. 
           [0028]      FIG. 3B  is a side view of the system of  FIG. 3A . 
           [0029]      FIG. 3C  is a partial cross-section view of the system of  FIG. 3A . 
           [0030]      FIG. 3D  is a side view of a system according to the present invention. 
           [0031]      FIG. 4A  is a perspective view of part of the system of  FIG. 3A . 
           [0032]      FIG. 4B  is a perspective view of a portion of the part of the system as shown in  FIG. 4A . 
           [0033]      FIG. 4C  is a perspective view of a portion of the part of the system as shown in  FIG. 4A . 
           [0034]      FIG. 4D  is a partial cross-section view of the system of  FIG. 3A . 
           [0035]      FIG. 5  is a perspective view of part of the system of  FIG. 3A . 
           [0036]      FIG. 6A  is a front top perspective view of a module of the system of  FIG. 3A . 
           [0037]      FIG. 6B  is a rear top perspective view of the module of  FIG. 6A . 
           [0038]      FIG. 6C  is a right (as viewed in  FIG. 6A ) side view of the module of  FIG. 6A . 
           [0039]      FIG. 6D  is a top view of the module of  FIG. 6A . 
           [0040]      FIG. 6E  is left (as viewed in  FIG. 6A ) side view of the module of  FIG. 6A . 
           [0041]      FIG. 6F  is a front view of the module of  FIG. 6A . 
           [0042]      FIG. 6G  is a front view of the module of  FIG. 6A . 
           [0043]      FIG. 6H  is a front view of the module of  FIG. 6A . 
           [0044]      FIG. 7A  is a front top perspective view of a module of the system of  FIG. 3A . 
           [0045]      FIG. 7B  is a rear top perspective view of the module of  FIG. 7A . 
           [0046]      FIG. 7C  is a left (as viewed in  FIG. 7A ) side view of the module of  FIG. 7A . 
           [0047]      FIG. 7D  is a top view of the module of  FIG. 7A . 
           [0048]      FIG. 7E  is a right (as viewed in  FIG. 7A ) side view of the module of  FIG. 7A . 
           [0049]      FIG. 7F  is a front view of the module of  FIG. 7A . 
           [0050]      FIG. 7G  is a front view of the module of  FIG. 7A . 
           [0051]      FIG. 7H  is a front view of the module of  FIG. 7A . 
           [0052]      FIG. 8A  is a front top perspective view of a module body according to the present invention. 
           [0053]      FIG. 8B  is a rear top perspective view of the module body of  FIG. 8A . 
           [0054]      FIG. 8C  is a left (as viewed in  FIG. 8A ) side view of the module body of  FIG. 8A . 
           [0055]      FIG. 8D  is a top view of the module body of  FIG. 8A . 
           [0056]      FIG. 8E  is a right (as viewed in  FIG. 8A ) side view of the module body of  FIG. 8A . 
           [0057]      FIG. 8F  is a front view of the module body of  FIG. 8A . 
           [0058]      FIG. 8G  is a front view of the module body of  FIG. 8A . 
           [0059]      FIG. 8H  is a front view of the module body of  FIG. 8A . 
           [0060]      FIG. 9A  is a cross-section view of a module according to the present invention of the system of  FIG. 3A . 
           [0061]      FIG. 9B  is a cross-section view of a module according to the present invention of the system of  FIG. 3A . 
           [0062]      FIG. 9C  is a perspective view of a sleeve of the module of  FIG. 9A . 
           [0063]      FIG. 9D  is a side view of the sleeve of  FIG. 9C . 
           [0064]      FIG. 9E  is a perspective view of a valve seat of the module of  FIG. 9A . 
           [0065]      FIG. 9F  is a rear view of a valve seat of the module of  FIG. 9E . 
           [0066]      FIG. 9G  is a side view of a valve seat of the module of  FIG. 9E . 
           [0067]      FIG. 10A  is a top view of a module according to the present invention of the system of  FIG. 3A . 
           [0068]      FIG. 10B  is side cross-section view of a portion of the system of  FIG. 3A . 
           [0069]      FIG. 10C  is a top cross-section view of the module of  FIG. 10A . 
           [0070]      FIG. 11A  is a top view of a module according to the present invention of the system of  FIG. 3A . 
           [0071]      FIG. 11B  is side cross-section view of a portion of the system of  FIG. 3A . 
           [0072]      FIG. 11C  is a top cross-section view of the module of  FIG. 10A . 
           [0073]      FIG. 12A  is a perspective view of a system according to the present invention. 
           [0074]      FIG. 12B  is front view of the system of  FIG. 12A . 
           [0075]      FIG. 13A  is a perspective view of part of the system of  FIG. 12A . 
           [0076]      FIG. 13B  is a perspective view of a portion of the part of the system as shown in  FIG. 12A . 
           [0077]      FIG. 13C  is a partial cutaway view of the system of  FIG. 12A . 
           [0078]      FIG. 14A  is a front top perspective view of a module of the system of  FIG. 3A . 
           [0079]      FIG. 14B  is a rear top perspective view of the module of  FIG. 14A . 
           [0080]      FIG. 14C  is a left (as viewed in  FIG. 14A ) side view of the module of  FIG. 14A . 
           [0081]      FIG. 14D  is a top view of the module of  FIG. 14A . 
           [0082]      FIG. 14E  is a right (as viewed in  FIG. 14A ) side view of the module of  FIG. 14A . 
           [0083]      FIG. 14F  is a front view of the module of  FIG. 14A . 
           [0084]      FIG. 14G  is a front view of the module of  FIG. 14A . 
           [0085]      FIG. 14H  is a front view of the module of  FIG. 14A . 
           [0086]      FIG. 15A  is a front top perspective view of a module according to the present invention. 
           [0087]      FIG. 15B  is a rear top perspective view of the module of  FIG. 15A . 
           [0088]      FIG. 15C  is a left (as viewed in  FIG. 15A ) side view of the module of  FIG. 15A . 
           [0089]      FIG. 15D  is a top view of the module of  FIG. 15A . 
           [0090]      FIG. 15E  is a right (as viewed in  FIG. 15A ) side view of the module of  FIG. 15A . 
           [0091]      FIG. 15F  is a front view of the module of  FIG. 15A . 
           [0092]      FIG. 15G  is a front view of the module of  FIG. 15A . 
           [0093]      FIG. 15H  is a front view of the module of  FIG. 15A . 
           [0094]      FIG. 16A  is a front top perspective view of a module body according to the present invention. 
           [0095]      FIG. 16B  is a rear top perspective view of the module body of  FIG. 16A . 
           [0096]      FIG. 16C  is a top view of the module body of  FIG. 16A . 
           [0097]      FIG. 16D  is a bottom view of the module body of  FIG. 16A . 
           [0098]      FIG. 16E  is a front view of the module body of  FIG. 16A . 
           [0099]      FIG. 16F  is a rear view of the module body of  FIG. 16A . 
           [0100]      FIG. 16G  is a left (as viewed in  FIG. 16A ) side view of the module body of  FIG. 16A . 
           [0101]      FIG. 16H  is a right (as viewed in  FIG. 16A ) side view of the module body of  FIG. 16A . 
           [0102]      FIG. 17A  is a cross-section view of a module according to the present invention of the system of  FIG. 12A . 
           [0103]      FIG. 17B  is a cross-section view of part of the system of  FIG. 13A . 
           [0104]      FIG. 18A  is a top view of a module according to the present invention of the system of  FIG. 3A . 
           [0105]      FIG. 18B  is side cross-section view of a portion of the system of  FIG. 3A . 
           [0106]      FIG. 18C  is a top cross-section view of the module of  FIG. 18A . 
           [0107]      FIG. 19A  is a top view of a module according to the present invention of the system of  FIG. 3A . 
           [0108]      FIG. 19B  is side cross-section view of a portion of the system of  FIG. 3A . 
           [0109]      FIG. 19C  is a top cross-section view of the module of  FIG. 19A . 
           [0110]      FIG. 20  is a cross-section view of a module according to the present invention. 
           [0111]      FIG. 21A  is a perspective view of a system according to the present invention. 
           [0112]      FIG. 21B  is a perspective view of a portion of the part of the system as shown in  FIG. 21A . 
           [0113]      FIG. 21C  is a top perspective view of part of the system of  FIG. 21A . 
           [0114]      FIG. 21D  is a perspective view of a module of the system of  FIG. 21A . 
           [0115]      FIG. 21E  is a cross-section view of the module of  FIG. 21D  along line E-E of  FIG. 21I . 
           [0116]      FIG. 21F  is a cross-section view along line F-F of  FIG. 21H . 
           [0117]      FIG. 21G  is a top view of the module of  FIG. 21D . 
           [0118]      FIG. 21H  is a side view of the module of  FIG. 21D . 
           [0119]      FIG. 21I  is a front view of the module of  FIG. 21D . 
           [0120]      FIG. 21J  is a cross-section view along line J-J of  FIG. 21G . 
           [0121]      FIG. 22A  is a front top perspective view of a module according to the present invention. 
           [0122]      FIG. 22B  is a rear top perspective view of the module of  FIG. 22A . 
           [0123]      FIG. 22C  is a left (as viewed in  FIG. 22A ) side view of the module of  FIG. 22A . 
           [0124]      FIG. 22D  is a top view of the module of  FIG. 22A . 
           [0125]      FIG. 22E  is a right (as viewed in  FIG. 22A ) side view of the module of  FIG. 22A . 
           [0126]      FIG. 22F  is a front view of the module of  FIG. 22A . 
           [0127]      FIG. 22G  is a front view of the module of  FIG. 22A . 
           [0128]      FIG. 22H  is a front view of the module of  FIG. 22A . 
           [0129]      FIG. 23A  is a front top perspective view of a module according to the present invention. 
           [0130]      FIG. 23B  is a rear top perspective view of the module of  FIG. 23A . 
           [0131]      FIG. 23C  is a left (as viewed in  FIG. 23A ) side view of the module of  FIG. 23A . 
           [0132]      FIG. 23D  is a top view of the module of  FIG. 23A . 
           [0133]      FIG. 23E  is a right (as viewed in  FIG. 23A ) side view of the module of  FIG. 23A . 
           [0134]      FIG. 23F  is a front view of the module of  FIG. 23A . 
           [0135]      FIG. 23G  is a front view of the module of  FIG. 23A . 
           [0136]      FIG. 23H  is a front view of the module of  FIG. 23A . 
           [0137]      FIG. 24A  is a front top perspective view of a module according to the present invention. 
           [0138]      FIG. 24B  is a cross-section perspective view of the module of  FIG. 24A  along line B-B of  FIG. 24D . 
           [0139]      FIG. 24C  is a cross-section view of the module of  FIG. 24A  along line C-C of  FIG. 24E . 
           [0140]      FIG. 24D  is a front view of the module of  FIG. 24A . 
           [0141]      FIG. 24E  is a top view of the module of  FIG. 24A . 
           [0142]      FIG. 24F  is a side view of the module of  FIG. 24A . 
           [0143]      FIG. 24G  is a bottom cross-section view of the module of  FIG. 24A  along line G-G of  FIG. 24F . 
           [0144]      FIG. 24H  is a rear view of the module of  FIG. 24A . 
           [0145]      FIG. 24I  is a top view of the module of  FIG. 24A . 
           [0146]      FIG. 24J  is a side view (opposite the side of  FIG. 24F ) of the module of  FIG. 24A . 
           [0147]      FIG. 25A  is a front top perspective view of a module body according to the present invention. 
           [0148]      FIG. 25B  is a top perspective view of the module body of  FIG. 25A . 
           [0149]      FIG. 25C  is a front view of the module body of  FIG. 25A . 
           [0150]      FIG. 25D  is a bottom view of the module body of  FIG. 16A . 
           [0151]      FIG. 25E  is a rear view of the module body of  FIG. 25A . 
           [0152]      FIG. 25F  is a side view of the module body of  FIG. 25A . 
           [0153]      FIG. 25G  is a side view of the module body of  FIG. 25A  (opposite the side of  FIG. 25F ). 
       
    
    
       [0154]    Presently preferred embodiments of the invention are shown in the above-identified figures and described in detail below. Various aspects and features of embodiments of the invention are described below and some are set out in the dependent claims. Any combination of aspects and/or features described below or shown in the dependent claims can be used except where such aspects and/or features are mutually exclusive. It should be understood that the appended drawings and description herein are of preferred embodiments and are not intended to limit the invention or the appended claims. On the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims. In showing and describing the preferred embodiments, like or identical reference numerals are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness. 
         [0155]    As used herein and throughout all the various portions (and headings) of this patent, the terms “invention”, “present invention” and variations thereof mean one or more embodiment, and are not intended to mean the claimed invention of any particular appended claim(s) or all of the appended claims. Accordingly, the subject or topic of each such reference is not automatically or necessarily part of, or required by, any particular claim(s) merely because of such reference. So long as they are not mutually exclusive or contradictory any aspect or feature or combination of aspects or features of any embodiment disclosed herein may be used in any other embodiment disclosed herein. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0156]    The system  500  shown in  FIG. 2  includes a derrick  502  from which extends a drillstring  504  into the earth  506 . The drillstring  504 , as is well known, can include drill pipes and drill collars. A drill bit  512  is at the end of the drillstring. A rotary system  514 , top drive system  526 , and/or a downhole motor  532  (“fluid motor”, “mud motor”) may be used to rotate the drillstring  504  and the drill bit  512 . A typical drawworks  516  has a cable or rope apparatus  518  for supporting items in the derrick  502 . A system  522  with one, two, or more mud pump systems  521  according to the present invention supplies drilling fluid  524  to the drillstring  504 . Drilling forms a wellbore  530  extending down into the earth  506 . 
         [0157]    During drilling, the drilling fluid  524  is pumped by pump(s)  521  of the system  522  into the drillstring  504  (thereby operating a downhole motor  532  if such an optional motor is used). Drilling fluid  524  flows to the drill bit  512 , and then flows into the wellbore  530  through passages in the drill bit  512 . Circulation of the drilling fluid  524  transports earth and/or rock cuttings, debris, etc. from the bottom of the wellbore  530  to the surface through an annulus  527  between a well wall of the wellbore  530  and the drillstring  504 . The cuttings are removed from the drilling fluid  524  so that it may be re-circulated from a mud pit or container  528  by the pump(s) of the system  522  back to the drillstring  506 . 
         [0158]    A system  10  according to the present invention as shown in  FIGS. 3A and 3B  has a main housing  12  mounted on a base  8  with an optional crane system  20  for lifting and moving system parts. A pedestal  21  of the crane system  20  is rotatably mounted on a bearing assembly  22  on the housing  12 . A lift apparatus  23  is movably mounted on a beam  24  and a support  25  extends down from the lift apparatus  23 . A chain hoist lift may be used with the structure shown which is attached to the support  25 . Motors  14  each drive pinions  16  which in turn drive a drive gear  18  (see  FIG. 3C ) to move pistons  19  for six removable pump modules  50  (as described below). A pressure relief apparatus (e.g. one or more relief valves) is provided for the modules  50  and, as shown, in one aspect, for each of the six modules  50  there is a pressure relief valve  13 . Optional rails  15  project up from the housing  12 . 
         [0159]    An oil pump  2  pumps lubricating oil to various parts of the system. A water pump  4  pumps water to a filtration system (not shown) and a cooler (not shown). The pumps are mounted on pump mounts  8   b  connected to the base  8 . Doors  3  and  5  (one each for each pump system  30 ) provide access to various internal parts of the system  10 . Drilling fluid enters the system  10  through an inlet  7  and is pumped out via the modules  50  to a main outlet  9 . 
         [0160]      FIG. 3C  shows the drive gear  18  with profiled cam structures  18   a  (driven by the pinions  16 ,  FIG. 3A ) which are cammed to sequentially move pump drive pistons  19  up and down sequentially in the modules  50  for pumping fluid. Each piston rod  19  is connected to a translation assembly  19   a.  The hydraulic lift cylinders  18   c  provide a constant force to maintain contact with the cam structures  18   a  and the assemblies  19   a.  The oil pump  2  pumps lubricating oil into an interior space  12   a  of the housing  12  to lubricate parts therein. Each piston  19  includes (e.g. see  FIG. 10B ) an extension rod  19   e,  a piston seal  19   s,  and a piston member  19   m  (often referred to as “the piston”). 
         [0161]      FIG. 3D  illustrates a system  10   a;  like the system  10  (like numerals indicate like parts) which has a housing  12   s  which is not tapered or conical as is the housing  12 ,  FIG. 3A , but rather is generally cylindrical (less complex than some other shapes and relatively easy to manufacture) and, which provides increased strength and rigidity. 
         [0162]      FIGS. 4A and 4B  show a holding structure  40  holding six pump modules  50  according to the present invention each with a valve assembly  100  removably disposed therein. Each module  50  fits between two arms  42  and rests on a shelf  44  of the holding structure  40 . The shelves  44  are connected to the base  8  and the arms  42  are centered around a center portion  43  and are connected to projections  8   a  of the base  8 . Fluid enters the modules  50  through inlets  62  of a central channel member  60 , flows into inlets  36  of each module  50 , and is pumped from each module  50  in a discharge outlet  32  (described below), into a discharge line  34 , and then to the main outlet  9 . An intersection  32   s  of the two flow channels,  32  and  34 , is shown, e.g. in  FIG. 11B . Each module  50  has an opening or chamber  52  down into which projects a drive piston  19 . Fluid is moved into a pump module  50  when the piston  19  moves up and is moved to the discharge outlet  32  when the piston  19  moves down. The channel member  60  includes a bowl  67  with a lower entry port  67   a.  Use of an entry port below the inlets  62  reduces or eliminates the settling of solids on the bottom of the bowl  67 . Blind flanges  32   f  close off lower bores of the modules. 
         [0163]    Optionally, a suction dampener  66  can be used at the inlet  7  to absorb shock waves in incoming fluid. In one aspect the suction dampener  66 , which has a generally cylindrical hollow shape lining an enlarged portion  7   a  of the inlet  7 , is made from a compressible material such as sponge or compressible closed cell foam. In certain aspects, fluid entering the inlet  7  at a pressure of, e.g., 50 psi can have pressure fluctuations or spikes, e.g. up to 150 psi. The suction dampener  66  absorbs some or substantially all of these pressure spikes to reduce or eliminate cavitation and so that a fluid at substantially constant pressure flows to an inlet portion  76  and to the inlets  62 . 
         [0164]      FIGS. 6A-6H  show a module  50  with a valve assembly  100 . Discharge pipes  34  connect to openings  34   a,    34   b,  on each module  50 . The discharge pipes  34  provide a common discharge conduit for the drilling fluid via channels in the modules and this allows the discharge outlet to be located on any of the modules. 
         [0165]      FIGS. 7A-7H  illustrate a module  300  according to the present invention, like the module  50 , with no side or top openings other than an opening  302  of an interior channel for a valve assembly  100 . Side and top openings, are to be added as needed. 
         [0166]      FIGS. 8A-8H  show a design for a module body  310  according to the present invention for use as a module in fluid pumping systems. 
         [0167]      FIGS. 9A and 9B  illustrate inner parts of a valve assembly  100 . Drilling fluid or mud is forced to the discharge outlet  32  when the piston  19  moves downward. Each piston  19  moves mud to the discharge outlet  32  in the same way. The mud then travels to the main outlet (e.g. outlet  9 ,  FIG. 4A ). The main outlet can be on any of the modules. A blind flange is bolted over an opening  32   p  of each modules which is not chosen as a location for the main outlet. The location of the main outlet is chosen during installation to ease installation of the pump. The main outlet is designed so that the pressure generated force acting at both ends of the outlet equal in magnitude and opposite in direction so that the net unbalanced force is zero. This is advantageous because the components of a discharge conduit do not have to be designed to prevent the pressure force from separating the conduit from the module. The result is a module that is lighter, less costly and easier to assemble. Also, in certain aspects, structures according to the present invention eliminate O-ring seals used in certain existing designs to attempt to help with the alignment of a discharge ring and modules. Each module has a discharge outlet. Any discharge outlet can be chosen as the main outlet. The other discharge outlets are secured with a blind flange. 
         [0168]    The valve assembly  100  is within a module  50  that has a body  502  with a multi-part bore  504  therethrough from an exterior end  506  of the body  502  to an interior end  508 . The valve assembly  100  has a cap  104  whose exterior threads threadedly mate with interior threads of a sleeve  170  with slots  170 s in the valve body  102 . A plate  106  is bolted with a bolt  107  to the cap  104 . A tool (not shown; e.g. an hydraulic tool) pushing against the plate forces the body  102  into the bore  504 . This makes it possible to remove the bolt  107  and thread an adapter into the cap  104  and pull the entire valve assembly (seats, valves, sleeve and all) out of the housing. Additionally, a grease port  100   g  (see  FIG. 11C ) that is positioned at the suction end of the sleeve allow a grease gun to be attached to the grease zerk at the grease port. The grease exerts a pressure on the back side of the sleeve which dislodges the sleeve from the housing, making it easier to remove the entire valve assembly. Thus, in one aspect, a valve assembly according to the present invention can be built ahead of time (e.g. at a remote site and/or on a rig, e.g. in a tool room) and therefore quickly change the valve assembly when it becomes necessary. 
         [0169]    A lug ring  112  connected to the body  102  has interior threading that threadedly mates with exterior threading on an end nut  114 . The end nut  114  holds the cap  104  and the body  102  in position in the bore  104 . The plate  106  abuts a shoulder  116  of the end nut  114 . Holes  118  in the end nut  114  facilitate its rotation. 
         [0170]    The valve assembly  100  includes a discharge valve  130  and a suction valve  150 . The discharge valve  130  has a valve member  135  that seats against a seat  132  in the bore  101  of the valve body  102  and the valve  150  has a valve member  137  that seats against a seat  134  in the bore  101  of the valve body  102 . 
         [0171]    The valve body  102  is slightly tapered (see, e.g.  FIGS. 9A and 9C ) and, in one aspect, the taper is on a section radially outboard of a discharge seat, e.g. about half way down the length of the sleeve OD; e.g. from a first diameter at the end with the cap  104  to a second smaller diameter at the end with the discharge valve  130 . In one aspect, the sleeve taper is radially outboard of the discharge valve seat taper. A bore  170   a  of the sleeve  170  has a corresponding taper. The bore  504  of the module body  502  also has a corresponding taper. An O-ring seal  175   e  is on the OD of the sleeve  170  and the body  102  has the portion  105  which sealingly abuts the seal surface  175  to provide a primary seal (sealed preventing fluid in the discharge chamber from leaking back around the discharge valve and into the pump chamber when the piston is on the suction stroke). In one aspect the taper on the OD of the sleeve  170  provides a robust seal between a pump chamber (e.g. chamber  52 ,  FIG. 4D ) and a discharge chamber. This taper is a primary seal and seals against the O-ring  175 . 
         [0172]    An O-ring  136  in a recess  138  in the body  102  sealingly abuts the seal surface  175  providing an optional secondary seal. A guide shaft  137   a  connected to the valve member  137  moves in a corresponding guide channel  102   b  in the body  102 . A guide shaft  130   a  connected to the valve member  130  moves in a corresponding guide channel  102   c  in the body  102 . The OD of the sleeve  170  is cylindrical except for the section radially outboard of portion  105 ; and the ID of the sleeve  170  is cylindrical except for the two tapers that accept the valve seats. Seals  175   a - 175   f  provide seals at their locations. 
         [0173]    A spring  142  with an end in contact with a retainer  147  urges the valve  135  of the discharge valve  130  in a closed position against the seat  132 . A spring  144  with an end against a retainer  146  urges the valve member  137  of the suction valve in a closed position against the seat  134 . Both retainers  146 ,  147  are bolted with bolts  149  to the body  102 . 
         [0174]    The sleeve  170  is interiorly tapered to correspond to the exterior taper of the valve seat  102 . Blind flanges  650   b  (see  FIG. 13B ) close off the bores  32   p.    
         [0175]      FIGS. 10A-10C  illustrate a suction stroke of a pump assembly  100 . The piston  19  is moved up (see  FIG. 10B ) by action of the hydraulic lift cylinders (see  FIG. 3C ) reducing the pressure on the piston side of the suction valve  150 , overcoming the force (e.g. about 25 psi) of the spring  144 , and resulting in unseating of the valve member  137  so that fluid is pumped into the module  50  through the inlet  36 . Initially, the pressure on both sides of the valve member  137  is equal (e.g. about 100 psi) until the piston moves. The discharge valve  130  remains closed and the interior space of the module, a pump chamber  141 , around the suction valve  150  is filled with fluid. 
         [0176]      FIGS. 11A-11c  illustrate a discharge stroke of the pump assembly  100 . The piston  19  moves down forcing the discharge valve member  135  to unseat opening the discharge valve  130 . The piston  19  moves down to force the fluid from the module  50  and out the discharge outlet  32  (see  FIG. 11B ). 
         [0177]    Due to the tapers of the body  102  and the sleeve  170 , by removing the nut  114 , the plate  116  and the cap  104 , the body  102  with the valves therein is removable from the body  502  of the module  50  and the sleeve  170  is removable from the body  502 . In a typical embodiment, the pump assembly&#39;s discharge pressure is e.g. about 7500 psi, e.g. 7526 psi. Tapered sleeve  170  is force fit into the module to seal the sleeve against the interior of the module. Such a force fit pre-expands the module  50 , e.g. 0.03 to 0.04 inches, thereby pre-stress an area around the O-ring  136  so the O-ring cannot move and, when under stress, does not scuff against the body  502 . During installation lubricant is used to prevent galling. The sleeve  170  and its internal components (including the seats  102  and  134 ) are removed and installed as a complete assembly. Optionally a discharge valve alone can be removed with the complete assembly removed, the inner parts of valves and seats can be inspected without disassembling the entire assembly. 
         [0178]    In one aspect a sleeve  170  is about ¾ inches thick and is made from alloy steel. 
         [0179]      FIGS. 12A and 12B  show a system  600  like the system  10  (like numerals indicate like parts). The system  600  has modules  650  (see also  FIG. 17A ,  FIG. 17B ) which are different from the modules  50 . 
         [0180]    The modules  650  have a body  602  with a multi-part bore  604  therethrough from an exterior end of the body  602  to an interior end. The body  602  has a first bore  602   a  and a second bore  602   b.  Optional bleed ports  650 p are provided. A discharge valve assembly  630  is in the bore  602   a  and a suction valve assembly  680  is in the bore  602   b.  The bore  602   a  is at an angle to the bore  602   b  (e.g. an acute angle ranging between 20 degrees and 45 degrees and, in one aspect, about 30 degrees). With a piston (like the piston  19 ,  FIG. 3C ) fluid is pumped into a chamber  652  of the module  650  via an inlet port  604  and is discharged from the module  650  into a discharge conduit  634  via an outlet port  606 . The outlet ports  606  are in fluid communication with side ports  612  which are in fluid communication with the discharge conduits  634 . The discharge conduits  634  are in fluid communication with a main outlet  609  providing a fluid communication path between all the modules on the discharge side of the pump. All the modules have their discharge outlets located so that they collect fluid after it passes their discharge valves and passes through their discharge conduits on the way to the discharge outlet  609  ( FIG. 13A ). A backside B of a suction valve seat is visible in  FIG. 14G . Part P of the valve case of the valve assembly is visible in  FIG. 14D . One module is selected at installation time as the best location for a discharge outlet. The other modules then have a blind flange  650   b  installed at the outlet port to secure the port. 
         [0181]    Optionally, lug rings  614 , like the lug ring  112 ,  FIG. 9A ; nuts  616 , like the nut  114 ,  FIG. 9A ; and caps  618 , like the cap  104 ,  FIG. 9A , are used to hold the valve assemblies in their bores. The valve assemblies  630 ,  680  are removable from the bores  602   a,    602   b,  respectively. 
         [0182]    A spring  642  with an end in contact with a retainer  647  urges a valve member  635  of the discharge valve assembly  630  in a closed position against a seat  632 . A spring  644  with an end against a retainer  646  urges a valve member  687  of the suction valve assembly  680  in a closed position against a seat  634 . The retainers  646 ,  647  abut shoulders  641 ,  643 , respectively. A guide shaft  657  of the discharge valve assembly  630  connected to the valve member  635  moves in a corresponding channel  658  in a valve body  692  to guide the valve member  635 . A guide shaft  655  of the suction valve assembly  680  connected to the valve member  687  moves in a corresponding channel  656  in a valve body  690  to guide the valve member  687 . A spacer  608  makes it possible for a variety of assembly cartridges to be interchangeable in the modules  650  as either suction valves or discharge valves. 
         [0183]    Seals  671 ,  672 ,  673 ,  674  seal the interfaces indicated between the valve body  692  and an interior surface of the bore  602   a.  Seals  675 ,  676 ,  677  seal the indicated interfaces between the valve body  690  and an interior surface of the bore  602   b.  A flange  650 f is used to bolt the fluid end of the pump to the deck. 
         [0184]      FIGS. 18A-18C  illustrate a suction stroke of a pump system with modules  650 . 
         [0185]    The piston  19  (e.g. as in a system like that of  FIG. 3C ) is moved up by action of a drive gear reducing the pressure on the piston side of the suction valve assembly  680 , overcoming the force (e.g. about 25 psi) of the spring  644 , and resulting in unseating of the valve member  687  so that fluid is pumped into the module  650  through the inlet  604 . Initially, the pressure on both sides of the valve member  687  is equal (e.g. about 100 psi). The discharge valve  630  remains closed and the interior pump chamber of the module around the suction valve assembly  680  is filled with fluid. 
         [0186]      FIGS. 19A-19C  illustrate a discharge stroke of the system  600 . The piston  19  moves down forcing the discharge valve member  635  to unseat opening the discharge valve  630 . The piston  19  moves down to force the fluid from the module  50  and out the discharge outlet  606 . 
         [0187]      FIGS. 15A-15H  illustrate a module  650   a  according to the present invention, like the module  650 , with no side or top openings other than openings of interior channels for two valve assemblies  630   a  and  680   a.  Side and top openings, are to be added as needed. 
         [0188]      FIGS. 16A-16H  show a design for a module body  650   b  according to the present invention for use as a module in fluid pumping systems. In certain aspects of the systems of the present invention, relatively thicker module housings are used which allow for the modules to be manufactured from less expensive, more readily available material (e.g. AISI8630M alloy steel instead of, e.g. S165M stainless steel). Thicker modules reduce the deflection of a module due to pressure variation. Reduced lower deflection of the housings improves cartridge seal life. 
         [0189]    In many prior systems, the discharge leaves each module separately and is transferred by an S-pipe to a discharge ring. Designs, according to the present invention, eliminate the discharge ring and S-pipe by incorporating a discharge conduit which provides a common communication of mud through the modules. 
         [0190]    In various systems according to the present invention described above, positioning the liner wash water transfer pump under the fluid modules removes the pump as a tripping hazard while consolidating liner wash drain lines within the pump support. On an upgrade power end design, in certain aspects, the drain line comes through the bottom of the chamber further reducing clutter. With the drains for the individual liner wash chambers positioned inboard so that they pass through the bottom plate rather than around it, the liner wash drain lines are positioned so that other components are more readily accessible. 
         [0191]    In certain aspects, placing the lube oil pump under the fluid modules reduces the suction line (item  2 ,  FIG. 3A ) length to the lube oil pump. 
         [0192]      FIG. 20  (a cross-section view) illustrates a module  800  according to the present invention for a drilling fluid pumping system with a valve assembly  820  according to the present invention in a body or “cage”  801 . The module  800 , in one aspect, has a body  802  with a wall thickness of at least two inches and a bore  804 . The body (or “cage”)  801  has slots  803 . The valve assembly  820  includes cartridges  821 ,  822  removably positioned in the bore  804  and held in place with a cap  805 , a nut  606 , and a lug ring  807 . The valve cartridges  821 ,  822  as shown are, but need not be, the same. In certain aspects, as is true with any module according to the present invention, the wall thickness of the modules  800  is greater than 2.36″ and, in one particular aspect, is 3.75″. 
         [0193]    The valve cartridge  821  acts as a suction valve and the valve cartridge  822  acts as a discharge valve. A piston (not shown, like the piston  19  described above) moves up and down (as does the piston  18 ) in a port  808  to pump fluid in through an inlet  809  and out through a discharge port (not shown in  FIG. 20 ) out of the side of the body  802 . 
         [0194]    The valve cartridge  821  has a body  832 , a retainer  834  connected to the body  801 , a valve member  836  movable toward and away from a seat  837 , and a guide shaft  838  connected to the valve member  836  that moves in a corresponding channel  839  in the body (or “cage”)  801 . A guide shaft  831  moves in a corresponding channel (not shown) of the retainer  834 . The valve member  836  can move to the right (as seen in  FIG. 20 ) in the body  801 . 
         [0195]    The valve cartridge  822  has a body  842 , a retainer  844  connected to the body  842 , a valve member  846  movable toward and away from a seat  847 , and a guide shaft  848  connected to the valve member  846  that moves in a corresponding channel  849  in the body  842 . A guide shaft  841  moves in a corresponding channel (not shown) of the retainer  844 . The valve member  846  can move to the right, as shown in  FIG. 20 , in the body or cage  842 .  0 -rings  851 ,  852 ,  853 ,  854  and  855  seal the interfaces at their locations. 
         [0196]    In a typical sequence of operation, the piston moves up opening the suction valve assembly  821  to pump fluid through the inlet port  809  into the bore  804 . Then the piston moves down, closing in the suction valve assembly  821  and opening the discharge valve assembly  822  to pump fluid out of the module  800  through the discharge port  811 . Weep holes  890  and  891  prevent a pressure build up behind the seals which could prevent the seals from energizing correctly. The weep holes are used in cartridge valve versions according to the present invention. 
         [0197]      FIG. 21A  shows a system  900  according to the present invention like the system of  FIG. 3A and 4A  (and like numerals indicate like parts). Instead of the modules  50 , the system  900  has removable modules  950 . As shown in  FIG. 21B , discharge outlets  952  of each module  950  communicate with each other via a discharge conduit  954  which itself is in fluid communication with a main system outlet  909 . Fluid communication with the discharge conduit  954  is via the outlets  952 . In certain aspects, such design allows the benefits of the previous designs to be incorporated in an existing pump base, thus allowing for existing pumps to be fitted with a module according to the present invention with thicker walls and with the discharge conduit. 
         [0198]    As shown in  FIG. 21C  and in  FIGS. 21D-21J , each module  950  has a body  960  with a valve assembly  980  removably mounted in a pump chamber  961 . The valve assembly  980  may be any valve assembly disclosed herein according to the present invention and, in one aspect, is as shown in  FIG. 21D . 
         [0199]    A cover  904  with an eyebolt  906  holds a spacer  908  in place in a bore  963  in the body  960 . A cap  912  with optional wrenching openings  914  threadedly engages a lug ring  916  to hold the cover  904 , etc. in place. The lug ring  916  is connected to the body  960 . 
         [0200]    Piston apparatuses  19   a  (e.g. like the apparatuses  19  as in  FIGS. 10A-11C ) pumps fluid into and out of the chamber  961 . 
         [0201]    A blind flange  920  closes off a bore  965  in the body  960 . A gasket  921  seals a flange-body interface and a seal  922  seals a flange-bore interface. Seals  925 ,  927  seal a spaced-body interface. 
         [0202]    The body  960  has an opening  960   a  which provides an inlet passage. The modules  950  (as are any modules disclosed herein according to the present invention) are removable from the system  900  by unbolting the discharge conduit, removing the liner, and unbolting the modules from the pump base. A blind flange  991  covers a discharge conduit  992  which may, upon removal of the flange  991 , be a main discharge for the system. 
         [0203]      FIGS. 22A-22H  show a module  950 . 
         [0204]      FIGS. 23A-23H  show a module  950   a.    
         [0205]    It is within the scope of the present invention for any module according to the present invention to be made from one large integral main body with the various holes, channels, bores, etc. formed therein. It is within the scope of the present invention for any module according to the present invention to be made from multiple pieces (two, three, or more) to form the main body. Such pieces may be bolted and/or welded together. For example, as shown in  FIGS. 24A-24G , a module  1000  according to the present invention has a body  1004  made of a top piece  1001  bolted with bolts  1006  to a bottom piece  1002 . 
         [0206]    A blind flange  1008  selectively closes off a discharge conduit  1009  (as does the blind flange  991 ,  FIG. 21D ). A valve assembly  1012  is like any valve assembly according to the present invention, e.g., but not limited to, like the valve assembly  980 ,  FIG. 21E . A discharge conduit  1014  is, e.g., like the conduit  952 ,  FIG. 21E . A cover  1016  is like the cover  904 ,  FIG. 21E ; a cap  1018  is like the cap  912 ,  FIG. 21E ; and a lug ring  1020  is like the lug ring  916 ,  FIG. 21E . An inlet  1024  is like the inlet  960   a,    FIG. 21E . A bone  1026  is like the bore  965 ,  FIG. 21E . A cap  1028  is like the cap  912 ,  FIG. 21E . Channels, bores, openings, and holes are provided for the module  1000  like those of the module  950 ,  FIG. 21E . 
         [0207]      FIGS. 25A-25G  illustrate a module body according to the present invention which a top piece  1011  (similar to the top piece  1001 ,  FIG. 24A ) and a bottom piece  1012  (similar to the bottom piece  1002 ,  FIG. 24A ). 
         [0208]    The present invention, therefore, provides in at least some embodiments, systems for pumping drilling fluid, the systems including: a base; a plurality of pumping apparatuses connected to the base, including a first pumping apparatus, each pumping apparatus including a pumping module with a module body; pumping structure for pumping fluid to and from each module; a conduit apparatus between each pair of adjacent modules so that fluid discharged from each module is flowable to the first pumping apparatus and into the module of the first pumping apparatus for discharge; and a main outlet for receiving fluid pumped by all the pumping apparatuses. 
         [0209]    The present invention, therefore, provides in at least some embodiments, a system for pumping drilling fluid, the system including: a base; a plurality of pumping apparatuses connected to the base, each pumping apparatus including a pumping module with a module body, each module body having a fluid inlet, a pumping chamber, a pumping chamber opening and a fluid discharge outlet, the fluid inlet in fluid communication with the pumping chamber, and a valve assembly in the module body for controlling fluid flow from the fluid inlet and through the pumping chamber to the fluid discharge outlet, the valve assembly passable through the pumping chamber opening into and out of the pumping chamber, pumping structure for pumping fluid to and from each pumping module; a main outlet for receiving fluid pumped by the pumping apparatuses; the plurality of pumping apparatuses including a first pumping apparatus, the main outlet at the first pumping apparatus of the plurality of pumping apparatuses, the first pumping apparatus&#39;s module comprising a first module, the first pumping apparatus&#39;s fluid discharge outlet comprising a first fluid discharge outlet, the first fluid discharge outlet in fluid communication with the main outlet; and a conduit apparatus between the fluid discharge outlets of each pair of adjacent modules so that fluid discharged from each module is flowable to the first pumping apparatus and into the first module for discharge through the main outlet. Such a system according to the present invention may have one or some (in any possible combination) of the following: wherein the conduit apparatuses are connectible between adjacent modules following installation of the modules on the base; each module having a main discharge bore so that any of the plurality of pumping apparatuses may be the pumping apparatus with the first pumping system; a base inlet apparatus in fluid communication with each fluid inlet of each pumping apparatus, the base inlet having an entry for receiving drilling fluid to be provided to each fluid inlet of each pumping apparatus; the base inlet includes a central channel member in fluid communication with each fluid inlet of each pumping apparatus, the central channel member having an entry port at a second level, and the fluid inlets of each pumping apparatus at a first level, the first level above the second level; a suction dampener adjacent the entry of the base inlet for dampening fluid flow therethrough providing fluid at a substantially constant pressure to the fluid inlets of the pumping apparatuses; each module body having module walls of sufficient thickness to reduce breathing of the module due to pressure variation; wherein the thickness of each module wall is greater than 2.36 inches; wherein the thickness of each module wall is at least 3.75 inches; and/or wherein each module body includes two parts bolted together, the two parts including a top part housing the valve assembly, and a bottom part having the fluid discharge outlet. 
         [0210]    The present invention, therefore, provides in at least some embodiments, a system for pumping drilling fluid through a wellbore extending into the earth, the system including: a base; a plurality of pumping apparatuses connected to the base, each pumping apparatus including a pumping module with a module body, each module body having a fluid inlet, a pumping chamber, a pumping chamber opening and a fluid discharge outlet, the fluid inlet in fluid communication with the pumping chamber, and a valve assembly in the pumping chamber for controlling fluid flow from the fluid inlet and through the pumping chamber to the fluid discharge outlet, the valve assembly passable through the pumping chamber opening into and out of the pumping chamber, pumping structure for pumping fluid to and from each module; a main outlet for receiving fluid pumped by the pumping apparatuses; the plurality of pumping apparatuses including a first pumping apparatus, the main outlet at the first pumping apparatus of the plurality of pumping apparatuses, the first pumping apparatus&#39;s module comprising a first module, the first pumping apparatus&#39;s fluid discharge outlet comprising a first fluid discharge outlet, the first fluid discharge outlet in fluid communication with the main outlet; a conduit apparatus between the fluid discharge outlets of each pair of adjacent modules so that fluid discharged from each module is flowable to the first pumping apparatus and into the first module for discharge through the main outlet; wherein the conduit apparatuses are connectible between adjacent modules following installation of the modules on the base; each module having a main discharge bore so that any of the plurality of pumping apparatuses may be the pumping apparatus with the first pumping system; a base inlet apparatus in fluid communication with each fluid inlet of each pumping apparatus; the base inlet having an entry for receiving drilling fluid to be provided to each fluid inlet of each pumping apparatus; the base inlet including a central channel member in fluid communication with each fluid inlet of each pumping apparatus; the central channel member having an entry port at a second level; and the fluid inlets of each pumping system at a first level, the first level above the second level. Such a system according to the present invention may have one or some (in any possible combination) of the following: a suction dampener adjacent the entry of the base inlet for dampening fluid flow therethrough providing fluid at a substantially constant pressure to the fluid inlet of the pumping apparatus; and/or wherein the thickness of each module wall is at least 3.75 inches. 
         [0211]    The present invention, therefore, provides in at least some embodiments, a system for pumping drilling fluid through a wellbore extending into the earth, the system including: a base; a plurality of pumping apparatuses connected to the base, each pumping apparatus including a pumping module with a module body, each module body having a fluid inlet, a pumping chamber, a pumping chamber opening and a fluid discharge outlet, the fluid inlet in fluid communication with the pumping chamber, and a valve assembly in the module body for pumping drilling fluid from the fluid inlet and through the pumping chamber to the fluid discharge outlet, pumping structure for pumping fluid to and from each module, the valve assembly including a suction valve and a discharge valve; the module body having a suction valve bore housing the suction valve; and the module body having a discharge valve bore housing the discharge valve. Such a system according to the present invention may have one or some (in any possible combination) of the following: a suction valve opening in the module body at an outer end of the suction valve bore, the suction valve passable through the suction valve opening for insertion into and removal from the suction valve bore, and a discharge valve opening in the module body at an outer end of the discharge valve bore, the discharge valve passable through the discharge valve opening for insertion into and removal from the suction valve bore; and/or wherein the suction valve bore is at an angle to the discharge valve bore. 
         [0212]    The present invention, therefore, provides in at least some embodiments, a system for pumping drilling fluid through a wellbore extending into the earth, the system including: a base; a plurality of pumping apparatuses connected to the base, each pumping apparatus including a pumping module with a module body, the module body having a fluid inlet, a pumping chamber, a pumping chamber opening and a fluid discharge outlet, the fluid inlet in fluid communication with the pumping chamber, a valve assembly bore in the module body, and a valve assembly in the valve assembly bore for controlling fluid flow from the fluid inlet, through the pumping chamber, and to the fluid discharge outlet, the valve assembly passable into and out of the valve assembly bore, pumping structure for pumping fluid to and from each module; the valve assembly bore having a first tapered area; the valve assembly having a second tapered area; and the second tapered area sealingly abutting the first tapered area and such a system wherein the valve assembly bore includes a removable sleeve encompassing the valve assembly and the first tapered area is on the removable sleeve. 
         [0213]    The present invention, therefore, provides in at least some embodiments, a method for pumping drilling fluid through a wellbore extending into the earth, the method including: pumping drilling fluid to a primary system for providing drilling fluid to a wellbore, the primary system being any pumping system according to the present invention, the method further comprising pumping drilling fluid from a fluid inlet of each pumping system to a main outlet and from the main outlet into the wellbore, then pumping the drilling fluid from the wellbore; and such a method wherein conduit apparatuses are connectible between adjacent modules following installation of the modules on the base, the method further comprising pumping drilling fluid from each module to a single one of the pumping apparatus, and pumping drilling fluid from the single one pumping apparatus to the main outlet. [ 0212 ] In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein and those covered by the appended claims are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited in any of the following claims is to be understood as referring to the step literally and/or to all equivalent elements or steps. The following claims are intended to cover the invention as broadly as legally possible in whatever form it may be utilized. The invention claimed herein is new and novel in accordance with 35 U.S.C. §102 and satisfies the conditions for patentability in §102. The invention claimed herein is not obvious in accordance with 35 U.S.C. §103 and satisfies the conditions for patentability in §103. This specification and the claims that follow are in accordance with all of the requirements of 35 U.S.C. §112. The inventors may rely on the Doctrine of Equivalents to determine and assess the scope of their invention and of the claims that follow as they may pertain to apparatus not materially departing from, but outside of, the literal scope of the invention as set forth in the following claims. All patents and applications identified herein are incorporated fully herein for all purposes. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function. In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.