Abstract:
An apparatus for preventing a threaded nut from unscrewing from a threaded bore of a device. The threaded nut has a circular periphery containing a plurality of apertures. The apparatus has a body with a first pin configured to insert into one of the apertures of the threaded nut, and a retainer that releasably holds the first pin within the aperture.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of and priority to U.S. Provisional Patent Application No. 61/351,537, filed on Jun. 4, 2010, and herein incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     This disclosure relates in general to reciprocating pumps, and in particular, to a packing nut lock for a reciprocating pump. 
     BACKGROUND OF THE DISCLOSURE 
     In oil field operations, reciprocating pumps are often used for various purposes. Some reciprocating pumps, generally known as “service pumps,” are typically used for operations such as cementing, acidizing, or fracing a well. Typically, these service pumps run for relatively short periods of time, but they operate on a frequent basis. Often they are mounted to a truck or a skid for transport to various well sites. A pump might operate several times a week. In many applications, several pumps are connected in parallel to a single flow line. 
     High pressure pumps are widely used in the petroleum industry for a variety of field operations relating to oil and gas wells. Such pumps deliver a fluid or slurry, which may carry solid particles (e.g., a sand proppant), at pressures up to 20,000 psi. A common type is a positive displacement pump having one or more plungers reciprocally movable in a corresponding pump chamber. Each chamber has an intake port for receiving fluid, a discharge port for exhaust, and a one-way flow valve in each port for preventing reverse flow. These valves require frequent maintenance. 
     With the many different ports and chambers in a high pressure pump, it is advantageous to ensure that threaded assemblies are securely threaded into the corresponding bores of the pump assembly. Unfortunately, many of these threaded assemblies are prone to inadvertently loosen. The pump experiences substantial vibration during operation at high power settings such that the threaded assemblies may overcome their initially applied torque and begin to “back out”, or rotate in a loosening direction. With respect to many of the threaded assemblies, should the assemblies continue to loosen, the closure, and in some instances, a quantity of high pressure fluid may be ejected from the pump housing and potentially cause damage or injury. Consequently, safety regulations demand that operators respond to any loosening of threaded assemblies by stopping the pump. That degrades efficiency and can necessitate the expense of a back-up pump for continuing a pumping operation while the primary pump is shut down. 
     SUMMARY 
     In a first aspect, embodiments are disclosed of an apparatus for preventing a threaded nut from unscrewing from a threaded bore of a device, the nut having a circular periphery containing a plurality of apertures, the apparatus comprising a body having a first pin configured to insert into one of the apertures of the nut; and a retainer that releasably holds the first pin within the aperture. 
     The apparatus releasably engages the threaded nut and prevents the threaded nut from rotating relative to the device, and thus prevents the threaded nut from loosening and backing out of the threaded bore. 
     In certain embodiments, the apparatus may further comprise a shank extending outward from and rigidly attached to the body and adapted to engage a non-rotatable portion of the device. 
     In certain embodiments, the apparatus may further comprise a substantially circumferentially planar surface on an outer end of the shank, opposite the body, the substantially circumferentially planar surface adapted to transfer a rotational force to the nut. 
     In certain embodiments, the retainer may comprise a second pin extending from the body at an angle relative to the first pin for engaging another aperture in the nut, and one of the pins is retractable relative to the body. 
     In certain embodiments, the pins may be at an acute angle to one another. 
     In certain embodiments, the apparatus may further comprise a resilient member mounted in engagement with the retractable pin to thereby bias the retractable pin toward an engaged position. 
     In certain embodiments, the second pin may have an axis that intersects the axis of the first pin. 
     In certain embodiments, the axis of the first pin and the axis of the second pin can be located in a single plane. 
     In certain embodiments, the retainer may comprise a second pin extending from the body at an angle relative to the first pin for engaging another aperture in the nut; one of the pins being retractable relative to the body, wherein the second pin may have an axis that intersects the axis of the first pin, and the axis of the first pin and the axis of the second pin are located in a single plane. 
     In a second aspect, embodiments are disclosed of an apparatus for preventing a threaded nut from unscrewing from a threaded bore of a device, the nut having a circular periphery containing a plurality of apertures, the apparatus comprising a body having a first pin configured to insert into one of the apertures of the nut and a second pin extending from the body at an angle relative to the first pin for engaging another aperture in the nut, one of the pins being retractable relative to the body, the second pin having an axis that intersects the axis of the first pin, and the axis of the first pin and the axis of the second pin being located in a single plane, and a shank extending outwardly from and being rigidly attached to the body and adapted to engage a non-rotatable portion of the device, the shank having an axis that intersects the axes of the first pin and the second pin, and the shank axis and the axes of the first and second pin are located in a single plane. 
     The apparatus releasably engages the threaded nut. If the threaded nut begins to rotate relative to the device, the shank makes contact with a non-rotatable portion of the device, thereby preventing the apparatus from rotating relative to the device, and thus, also preventing the threaded nut from rotating any further relative to the device. The apparatus thus prevents the threaded nut from loosening and backing out of the threaded bore. In certain embodiments, the axes of the pins can be at an acute angle to one another. 
     In certain embodiments, the retractable pin may further comprise a resilient member housed within the shank and in engagement with the retractable pin to thereby bias the retractable pin toward an engaged position. 
     In certain embodiments, the apparatus may further comprise a substantially circumferentially planar surface on an outer end of the shank, opposite the body, the substantially circumferentially planar surface adapted to transfer a rotational force to the nut. 
     In a third aspect, embodiments are disclosed of a reciprocating pump assembly comprising a reciprocating pump having a housing, a threaded nut in engagement with a threaded bore in the reciprocating pump housing, an apparatus for retaining the threaded nut in engagement with the threaded bore in the reciprocating pump housing, the apparatus having a body with a portion in releasable engagement with the nut and a retainer that releasably retains the body in engagement with the nut, and a shank extending from the body and adapted to engage a non-rotatable portion of the reciprocating pump to prevent rotation of the body relative to the pump housing, which in turn, prevents the threaded nut from rotating relative to the pump housing. 
     In certain embodiments, the bore may have a bore axis and the threaded nut has a circular periphery containing a plurality of apertures located in and spaced around the periphery, each of the apertures having an aperture axis that intersects the bore, the apparatus comprising a first pin extending from the body along one of the aperture axes and into one of the apertures, and the retainer comprises a second pin extending along another one of the aperture axes and into another one of the apertures. 
     In certain embodiments, the first and second pins may be at an acute angle to one another. 
     In certain embodiments, the first pin may be retractable. 
     In certain embodiments, the retractable pin may further comprise a resilient member housed within the shank and in engagement with the retractable pin to thereby bias the retractable pin toward an engaged position. 
     In a fourth aspect, embodiments are disclosed of a method for preventing a threaded nut from unscrewing from a threaded bore of a device, the nut having a circular periphery containing a plurality of apertures, the method comprising the steps of providing a body with a pin, inserting the pin into one of the apertures, retaining the body and the pin with the nut, and transferring any forces due to a tendency of the nut to unscrew to a fixed portion of the device. 
     In certain embodiments, the method may further comprise rotating the nut, body, and pin in an unscrewing direction until a protruding portion of the body contacts a fixed portion of the device, thereby preventing further rotation of the nut in the unscrewing direction. 
     Other aspects, features, and advantages will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, which are a part of this disclosure and which illustrate, by way of example, principles of any disclosures disclosed. 
    
    
     
       DESCRIPTION OF THE FIGURES 
       The accompanying drawings facilitate an understating of the various embodiments. 
         FIG. 1  is an elevational view of a reciprocating pump assembly; 
         FIG. 2  is a top plan schematic view of the reciprocating pump assembly of  FIG. 1 ; 
         FIG. 3  is a sectional view of the pump assembly shown in  FIG. 1 ; 
         FIG. 4  is a front plan view of a packing nut lock in accordance with the present disclosure; 
         FIG. 5  is a perspective view of the packing nut lock of  FIG. 4 ; 
         FIG. 6  is a spring pin assembly in accordance with the present disclosure; 
         FIG. 7  is a sectional view of a portion of a reciprocating pump assembly in accordance with the present disclosure, with a packing nut lock installed in a disengaged position; 
         FIG. 8  is a sectional view of a portion of a reciprocating pump assembly in accordance with the present disclosure, with a packing nut lock installed in an engaged position; 
         FIG. 9  is a sectional view of a portion of a reciprocating pump assembly in accordance with the present disclosure, with a packing nut lock installed in an engaged position; 
         FIG. 10  is a perspective view of a portion of a reciprocating pump assembly in accordance with the present disclosure, with a packing nut lock installed and in an engaged position, and in contact with a stay rod; 
         FIG. 11  is a front plan view of a packing nut lock in accordance with an alternate embodiment of the present disclosure; 
         FIG. 12  is a perspective view of the packing nut lock of  FIG. 11 ; and 
         FIG. 13  is a sectional view of the packing nut lock in accordance with an alternate embodiment of the present disclosure, and taken along the line A-A of  FIG. 11 . 
         FIG. 14  is an exploded view of a spring pin assembly in accordance with an alternate embodiment of the present disclosure; 
         FIG. 15  is a perspective view of a packing nut lock and tool in accordance with an alternate embodiment of the present disclosure; 
         FIG. 16  is an additional perspective view of the packing nut lock and tool of  FIG. 15 , connected to a packing nut; and 
         FIG. 17  is a sectional view of the packing nut lock and tool taken along the line B-B of  FIG. 16 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 and 3 , a reciprocating pump assembly or pump  12  includes a crankshaft housing  13  that comprises the outer surface of the reciprocating pump  12 . A plurality of stay rods  15  attach to a side of the crankshaft housing  13  and extend to a fluid cylinder housing  17 . Each cylinder typically includes a fluid inlet  19  and a fluid outlet  21 . As best shown in  FIGS. 1 through 3 , an access bore cover  22  connects to an end of the cylinder housing  17 , opposite the plurality of stay rods  15 . The pump  12  can easily be mounted to a trailer that can be towed between operational sites, or to a skid for use in offshore operations. Accordingly, a pump assembly may include the pump  12  mounted directly to the ground or a support structure, a skid, a trailer, etc. 
     Referring to  FIG. 2 , the plurality of stay rods  15  are segmented into three portions, each portion having multiple stay rods  15 , and each portion comprising a plunger throw  23 . The reciprocating pump  12  (as shown in  FIG. 2 ) has three plunger throws  23 , a configuration which is commonly known as a triplex pump, but the stay rod can also be segmented for five plunger throws, a configuration which is commonly known as a quintuplex pump. The present description is directed to a triplex pump, but as will be readily apparent to those skilled in the art, the features and aspects described are easily applicable for a quintuplex pump or other types of pumps. Each plunger throw  23  houses a plunger or pony rod  33  ( FIG. 3 ) that extends to the cylinder housing  17 . As shown in  FIG. 2 , each of the plunger throws  23  extend in the same longitudinal direction as each other from the crankshaft housing  13 . 
     Referring to  FIG. 3 , a portion of the reciprocating pump  12  that is housed within the crankshaft housing  13  is shown. The crankshaft housing  13  houses a crankshaft  25 , which is typically mechanically connected to a motor (not shown). The motor rotates the crankshaft  25  in order to drive the reciprocating pump  12 . In one embodiment, the crankshaft  25  is cammed so that fluid is pumped from the cylinder housing  17  at alternating times. As will be readily apparent by those skilled in the art, alternating the cycles of pumping fluid from the cylinder housing  17  helps minimize the primary, secondary, and tertiary (et al.) forces associated with the reciprocating pump  12 . 
     In one embodiment, a gear  24  is mechanically connected to the crankshaft  25  and is rotated by the motor through a gear  26 . A connector rod  27  connects to a crosshead  29  through a crosshead pin  31 , which holds the connector rod  27  laterally relative to the crosshead  29 . The connector rod  27  pivots about the crosshead pin  31  as the crankshaft  25  rotates with the other end of the connector rod  27 . The pony rod  33  extends from the crosshead  29  in a longitudinally opposite direction from the connector rod  27 . The connector rod  27  and the crosshead  29  convert rotational movement of the crankshaft  25  into longitudinal movement of the pony rod  33 . 
     A plunger  35  is connected to the pony rod  33  for pumping the fluid which passes through the cylinder housing  17  during operation of the pump  12 . A packing  36  surrounds the plunger  35 . A packing nut  38  is threaded into the cylinder housing  17 , and acts to maintain the packing  36  in the proper position within the packing bore  37 . A number of holes or apertures  40  ( FIGS. 7 ,  8 , and  10 ) extend along the outer diameter of the rim of the packing nut  38 . The holes  40  are for engagement by a spanner to tighten and loosen the packing nut  38 . When properly positioned, the packing  36  and the packing nut  38  maintain the necessary pressure between the plunger  35  and the packing  36 , and prevent the packing bore  37  from leaking. 
     The cylinder housing  17  connects to the ends of the stay rods  15 , extending away from the crankshaft housing  13  ( FIG. 1 ). The cylinder housing  17  includes a plurality of interior or cylinder chambers  39 , which is where the plungers  35  compress the fluid being pumped by the reciprocating pump  12 . The cylinder housing  17  also typically includes an inlet valve  41  and an outlet valve  43 . The valves  41 ,  43  are usually spring-loaded valves and are actuated by a predetermined differential pressure. The inlet valve  41  actuates to control fluid flow through the fluid inlet  19  into the cylinder chamber  39 , and the outlet valve  43  actuates to control fluid flow through the fluid outlet  21  from the cylinder chamber  39 . Other valve arrangements and configurations of the fluid end of equivalent functionality are envisaged. 
     The plunger  35  reciprocates, or moves longitudinally toward and away from the cylinder housing  17  as the crankshaft  25  rotates. As the plunger  35  moves longitudinally away from the cylinder chamber  39 , the pressure of fluid inside the chamber  39  decreases, creating a differential pressure across the inlet valve  41 , which actuates the valve  41  and allows the fluid to enter the cylinder chamber  39  from the fluid inlet  19 . The fluid being pumped enters the cylinder chamber  39  as the plunger  35  continues to move longitudinally away from the cylinder housing  17  until the pressure difference between the fluid inside the cylinder chamber  39  and the fluid in the fluid inlet  19  is small enough for the inlet valve  41  to actuate its closed position. On the return stroke as the plunger  35  begins to move longitudinally towards the cylinder housing  17 , the pressure on the fluid inside of the cylinder chamber  39  begins to increase. Fluid pressure inside the cylinder chamber  39  continues to increase as the plunger  35  approaches the cylinder housing  17  until the differential across the outlet valve  43  is large enough to actuate the outlet valve  43  and allow the fluid to exit the cylinder housing  17  through the fluid outlet  21 . In one embodiment, fluid is only pumped across one side of the plunger  35 ; therefore, the reciprocating pump  12  is a single-acting reciprocating pump. As the operation of the pump  12  is conventional, it will not be described in further detail. During operation of the pump  12 , vibration and reciprocating forces from the plunger  35  may cause the packing nut  38  to loosen or back out. As the packing nut  38  backs out, the packing  36  is affected, which may result in pressure differentials and leakage of fluid from the packing bore  37 . 
     Referring to  FIGS. 4 and 5 , in this embodiment, a packing nut lock  67  is comprised of a main body  69  having a generally elongate, arcuate shape. In this embodiment, the main body  69  generally subtends an angle of around one sixth of a circle and has a top surface  71  and a bottom surface  73 . The bottom surface  73  of the main body  69  is substantially geometrically complimentary to the rim of the packing nut  38  and is adapted to be in abutting contact with a portion of the outer diameter of the rim of the packing nut  38  ( FIGS. 7 and 8 ). Two apertures  75 ,  77  are located in and extend through opposite end portions of the main body  69 , with each aperture  75 ,  77  extending from the top surface  71  through to the bottom surface  73 . In this embodiment, a fixed cylindrical pin  79  having an upper flange portion  81  with a greater diameter than a lower portion  83 , is inserted into and passes through one of the apertures  75 . In this embodiment, the cylindrical pin  79  is welded to the main body  69 . However, in additional embodiments, the cylindrical pin  79  may be cast as one member with main body  69 , or may be connected to main body  69  by other means. The lower portion  83  of the fixed cylindrical pin  79  is adapted to be inserted into one of the holes  40  that extend around the outer diameter of the rim of packing nut  38 , when the packing nut lock  67  is engaged ( FIG. 8 ). 
     Although the packing nut  38  illustrated with the current embodiment is circular in shape, the packing nut  38  may have alternative shapes. For example, the packing nut  38  may be hexagonal, square, etc., in additional embodiments. In such additional embodiments, the main body  69  of the packing nut lock  67  may be shaped to be geometrically complimentary to the shape of the packing nut  38 . For example, if the packing nut  38  were hexagonal in shape, the main body  69  of the packing nut lock  67  would be geometrically complimentary to the hexagonal shape of the packing nut  38 . 
     A spring pin assembly  85  is connected to the top surface  71  of the main body  69 , above the other aperture  77 . Referring to  FIG. 6 , the spring pin assembly  85  is comprised of a collar  87 , a center pin  89 , a resilient member or spring  91 , a retaining nut  93 , and a handle  95 . In this embodiment, the collar  87  is a hollow bodied cylindrical member having a closed end  97  and an open end  99 . The closed end  97  of the collar  87  has an aperture  101  located in and extending therethrough that is aligned with the apertures  77  in the main body  69 . In this embodiment, the collar  87  is welded to the main body  69 . However, in additional embodiments, the collar  87  may be cast as one member with the main body  69 , or may be connected to the main body  69  by other means. In this embodiment, the inner surface of the open and  99  of the collar  87  has threads located therein. An elongated aperture or slot  103  is located in and extends through the cylindrical collar  87  along the portion of its outer surface. 
     The center pin  89  has a cylindrical medial flange portion  105  having a diameter that is slightly less than the inner diameter of the collar  87 , such that the center pin  89  is positioned within the collar  87 . In this embodiment, a threaded aperture  107  is located in and extends through the medial flange portion  105  of the center pin  89 , substantially perpendicular to the axis of the center pin  89 . A cylindrical locking pin portion  109  of the center pin  89  has a smaller diameter than the flange portion  105  and extends axially downward therefrom. The locking pin portion  109  of the center pin  89  is adapted to be inserted into one of the holes  40  that extend along the outer diameter of the rim of the packing nut  38  when the packing nut lock  67  is engaged ( FIG. 8 ). A cylindrical guide pin portion  111  of the center pin  89  has a diameter which is smaller than the flange portion  105  and smaller than the locking pin portion  109 , and extends axially upward from the flange portion  105 , in a direction opposite to the locking pin portion  109 . 
     Although the holes  40  of the packing nut  38  illustrated with the current embodiment are circular in shape, the holes  40  may have alternative shapes. For example, the holes  40  may be hexagonal, square, etc. in additional embodiments. In such additional embodiments, the fixed pin  79  and the center pin  89  may be shaped to be geometrically complimentary to the shape of the holes  40  in the packing nut  38 . For example, if the holes  40  of the packing nut  38  were hexagonal in shape, the fixed pin  79  and the center pin  89  of the packing nut lock  67  would be geometrically complimentary to the hexagonal shape of the holes  40  of the packing nut  38 . 
     Referring to  FIG. 9 , in this embodiment the handle  95  is cylindrical and has threads located in the exterior surface of one of its ends  113 . The threaded end  113  of the handle  95  threadingly engages with the threaded aperture  107  in the flange portion  105  of the center pin  89 , thereby connecting the handle  95  and the center pin  89 . The handle  95  extends radially outwardly from the flange portion  105  of the center pin  89  and also passes through the elongated aperture or slot  103  in the collar  87 . The handle  95  extends a desired distance radially outward from the collar  87 . The handle  95  is adapted to move vertically within the aperture  103  of the collar  87  to thereby move the center pin  89 , and in particular the locking pin portion  109 , from an engaged position to a disengaged position. 
     The cap or retaining nut  93  has a first end  115  and a second end  117 . In this embodiment, the retaining nut  93  is cylindrical and has threads on its exterior surface that are threadably engaged with the threads on the inner surface of the open end  99  of the collar  87 . The retaining nut  93  thereby seals or caps the open end  99  of the collar  87  when the two are connected to one another. The second end  117  of the retaining nut  93  has an aperture  119  located therein with a diameter slightly larger than the diameter of the guide pin portion  111  of the center pin  89 . The guide pin portion  111  of the center pin  89  is captured within the aperture  119  of the retaining nut  93 . As the center pin  89 , and in particular, the locking pin portion  109  is moved vertically upward from an engaged position to a disengaged position, the guide pin portion  111  of the center pin  89  travels further into the aperture  119  in the retaining nut  93 . 
     In this embodiment, the spring  91  surrounds the guide pin portion  111  of the center pin  89  and abuts against the retaining nut  93  on one end and the flange portion  105  of the center pin  89  on the other end. The spring  91  acts to bias the center pin  89  into an engaged position, with the locking pin portion  109  of the center pin  89  extending fully outward through the aperture  77  in the main body  69  ( FIGS. 4 and 5 ). 
     Referring to  FIG. 9 , in operation, once the packing  36  has been inserted around the plunger  35  within the packing bore  37 , the packing nut  38  is threaded into the body of the cylinder housing  17 . Referring generally to  FIG. 7 , a spanner (not shown) is inserted into holes or apertures  40  on the outer diameter of the rim of the packing nut  38 , and the packing nut  38  is securely tightened. The packing nut lock  67  is then connected to the packing nut  38 . The fixed cylindrical pin  79  is machined so that the smaller diameter portion  83  will fit into one of the holes  40  extending around the rim of the packing nut  38 . The packing nut  67  is positioned so that the smaller diameter portion  83  of the fixed cylindrical pin  79  is positioned within one of the holes  40  of the packing nut  38 . The center pin  89  of the spring pin assembly  85  is positioned in a disengaged position within the collar  87  by positioning the handle  95  to its most upward position within the elongated aperture  103 . Force is maintained against the handle  95  to compress the spring  91  and to allow the center pin  89  to maintain the disengaged position. The guide pin portion  111  of the center pin  89  fully enters the aperture  119  in the retaining nut  93 . The main body  69  of the packing nut lock  67  is positioned so that the bottom surface  73  is in abutting contact with the outer diameter of the rim of the packing nut  38 , and the aperture  77  is positioned directly above another hole  40  in the packing nut  38 . 
     Referring generally to  FIGS. 8 and 9 , once the packing nut lock  67  is properly positioned, the force is removed from the handle  95  of the spring pin assembly  85 , and the spring  91  expands and pushes the center pin  89  downward relative to the collar  87 . The locking pin portion  109  of the center pin  89  fully extends through the aperture  77  in the main body  69  of the packing nut lock  67  and engages another hole  40  in the packing nut  38 . Based on the angles of the fixed cylindrical pin  79  and the center pin  89  relative to one another within the holes  40  of the packing nut  38 , the packing nut lock  67  is securely engaged with the packing nut  38 , and cannot be removed without disengaging the spring pin assembly  85 . 
     Referring to  FIG. 10 , the spring pin assembly  85 , and in particular, the collar  87  and the retaining cap  95 , extend radially outward from the center of the packing bore  37  by a distance that is greater than or equal to the distance from the center of the packing bore to the stay rod  15 . If the packing nut  38  begins to rotate relative to the housing  17 , the spring pin assembly  85  makes contact with the stay rod  15 , thereby preventing the packing nut lock  67  from rotating relative to the housing  17 , and thus, also preventing the packing nut  38  from rotating any further relative to the housing  17 . As a result, the packing nut lock  67  prevents the packing nut  38  from loosening and backing out of the packing bore  37 . 
     Referring to  FIGS. 11 and 12 , in an alternate embodiment, a packing nut lock  121  is comprised of a main body  123  having a generally elongate, arcuate shape. In this alternate embodiment, the main body  123  generally subtends an angle of about one sixth of a circle and has a top surface  125  and a bottom surface  127 . The bottom surface  127  of the main body  123  is substantially geometrically complimentary to the rim of the packing nut  38  and is adapted to be in abutting contact with a portion of the outer diameter of the rim of the packing nut  38 . An aperture  131  is located in and extends through an end portion of the main body  123 , with the aperture  131  extending from the top surface  125  through to the bottom surface  127 . In this alternate embodiment, a fixed cylindrical pin  133  having an upper concave portion  135  with a lesser diameter than a lower portion  137 , extends from the bottom surface  127  of the main body  123 , opposite the end portion of the main body  123  through which the aperture  131  extends. In this alternate embodiment, the cylindrical pin  133  is cast as one member with the main body  123 . However, in additional embodiments, the cylindrical pin  133  may be welded to the main body  123 , or may be connected to the main body  123  by other means. The fixed cylindrical pin  133  is adapted to be inserted into one of the holes  40  that extend along the outer diameter of the rim of the packing nut  38  when the packing nut lock  121  is engaged. 
     A spring pin assembly  139  is connected to the top surface  125  of the main body  123 , above the aperture  131 . Referring to  FIGS. 13 and 14 , the spring pin assembly  139  is comprised of a collar  141 , a center pin  143 , a resilient member or spring  145 , and a handle  147 . In this embodiment, the collar  141  is a hollow bodied cylindrical member having a closed end  149  and an open end  151 . The open end  151  of the collar  141  is aligned with the aperture  131  in the main body  123 . In this alternate embodiment, the collar  141  is welded to the main body  123 . However, in additional embodiments, the collar  141  may be cast as one member with the main body  123 , or may be connected to the main body  123  by other means. An elongated aperture or slot  153  is located in and extends through the cylindrical collar  141  along a portion of its outer surface. 
     The center pin  143  is a cylindrical member having a diameter that is slightly less than the inner diameter of the collar  141 , such that the center pin  143  is positioned within the collar  141 . In this embodiment, a threaded aperture  155  is located in and extends through a medial portion of the center pin  143 , substantially perpendicular to the axis of the center pin  143 . An end portion  157  of the center pin  143  is adapted to be inserted into one of the holes  40  that extend around the outer diameter of the rim of the packing nut  38  when the packing nut lock  121  is engaged. 
     In this embodiment, the handle  147  is cylindrical and has threats located in the exterior surface of one of its ends  159 . The threaded end  159  of the handle  147  threateningly engages the threaded aperture  155  in the medial portion of the center pin  143 , thereby connecting the handle  147  and the center pin  143 . The handle  147  extends radially outward from the center pin  143  before passing through the elongated aperture or slot  153  in the collar  141 . The handle  147  extends a desired distance radially outward from the collar  141 . The handle  147  is adapted to move vertically within the aperture  153  of the collar  141  to thereby move the center pin  143 , and in particular, the end portion  157 , from an engaged position to a disengaged position. 
     In this embodiment, the spring  145  is positioned within the collar  141  between the closed end  149  of the collar  141  and the center pin  143 . The spring  145  acts to bias the center pin  143  in an engaged position, with the end portion  157  of the center pin  143  extending fully outward through the aperture  131  in the main body  123  ( FIGS. 11 and 12 ). 
     In operation, the alternate embodiment packing nut lock  121  is installed on the reciprocating pump  12  and engaged/disengaged with the packing nut  38  just as for the first embodiment of a packing nut lock  67  described herein. 
     Referring to  FIGS. 15 through 17 , in an alternate embodiment, a packing nut lock and tool  161  is comprised of a main body  163  having a generally elongate, arcuate shape. The packing nut lock and tool  161  of this alternate embodiment may be employed similarly to the packing nut locks  67 ,  121  of the aforementioned embodiments set forth herein. The packing nut lock and tool  161  of this alternate embodiment may also be utilized with other portions of the reciprocating pump  12 . For example, the packing nut lock and tool  161  may be utilized with the packing nut  38 , a discharge flange, a gauge port, or any item that incorporate holes or apertures on the outer diameter of the rim of the item. For illustration purposes only, the packing nut lock and tool  161  shown in  FIG. 15  will be discussed in relationship to the packing nut  38 . 
     In this alternate embodiment, the main body  163  of the packing nut lock and tool  161  generally subtends an angle of around one fifth of a circle and has a top surface  165  and a bottom surface  167 . The bottom surface  167  of the main body  163  is substantially geometrically complimentary to the rim of the packing nut  38  and is adapted to be in abutting contact with a portion of the outer diameter of the rim of the packing nut  38 . Referring to  FIG. 17 , an aperture  169  is located in and extends through an end portion of the main body  163 , with the aperture  169 , extending from the top surface  165  through to the bottom surface  167 . In this alternate embodiment, a fixed cylindrical pin  171  having an upper concave portion  173  with a lesser diameter than a lower portion  175 , extends from the bottom surface  167  of the main body  163 , opposite the end portion of the main body  163  through which the aperture  169  extends. In this alternate embodiment, the cylindrical pin  171  is cast as one member with the main body  163 . However, in additional embodiments, the cylindrical pin  171  may be welded to the main body  163 , or may be connected to main body  163  by other means. The fixed cylindrical pin  171  is adapted to be inserted into one of the holes  40  that extend along the outer diameter of the rim of packing nut  38  when the packing nut lock and tool  161  are engaged. 
     A cylindrical arm  176  extends from the top surface  165  of the main body  163  of the packing nut lock and tool  161 , just above the fixed cylindrical pin  171 . In this embodiment, the cylindrical arm  176  is cast as one member with the main body  163 . However, in additional embodiments, the cylindrical arm  176  may be welded to the main body  163 , or may be connected to the main body  163  by other means. In this embodiment, a substantially rectangular engagement member  177  is connected to the end of the cylindrical arm  176 , opposite the main body  163  of the packing nut lock and tool  161 . The substantially rectangular engagement member  177  has two substantially planar contact surfaces  178 ,  179  on opposite sides of and parallel to one another. The planar contact surfaces  178 ,  179  extend in a plane that intersects and is substantially perpendicular to the arc of the main body  163 . The planar contact surface  178 ,  179  are adapted to act as a contact point for a force to be exerted on the packing nut lock and tool  161 , for example, the force of a sledge hammer. 
     A spring pin assembly  181  is connected to the top surface  165  of the main body  163 , above the aperture  169 . Referring to  FIG. 17 , the spring pin assembly  181  is comprised of a collar  183 , a center pin  185 , a resilient member or spring  187 , and a handle  189 . In this embodiment, the collar  183  is a hollow bodied cylindrical member having a closed end  191  and an open end  193 . The open end  193  of the collar  183  is aligned with the aperture  169  in the main body  163 . In this alternate embodiment, the collar  183  is cast as one member with the main body  163 . However, in additional embodiments, the collar  183  may be welded to the main body  163 , or may be connected to the main body  163  by other means. An elongated aperture or slot  195  is located in and extends through the cylindrical collar  183  along a portion of its outer surface. 
     The center pin  185  is a cylindrical member having a diameter that is slightly less than the inner diameter of the collar  183 , such that the center pin  185  is positioned within the collar  183 . In this embodiment, a threaded aperture  197  is located in and extends through a portion of the center pin  185 , substantially perpendicular to the axis of the center pin  185 . An end portion  199  of the center pin  185  is adapted to be inserted into one of the holes  40  that extend along the outer diameter of the rim of the packing nut  38  when the packing nut lock and tool  161  is engaged. 
     In this embodiment, the handle  189  is cylindrical and has threads located in the exterior surface of one of its ends  201 . The threaded end  201  of the handle  189  threadingly engages the threaded aperture  197  in the portion of the center pin  185 , thereby connecting the handle  189  and the center pin  185 . The handle  189  extends radially outward from the center pin  185  before passing through the elongated aperture or slot  195  in the collar  183 . The handle  189  extends a desired distance radially outward from the collar  183 . The handle  189  is adapted to move vertically within the aperture  195  of the collar  183  to thereby move the center pin  185 , and in particular, the end portion  199 , from an engaged position to a disengaged position. 
     In this embodiment, the spring  187  is positioned within the collar  183  between the closed end  191  of the collar  183  and the center pin  185 . The spring  187  acts to bias the center pin  185  in an engaged position, with the end portion  199  of the center pin  185  extending fully outward through the aperture  169  in the main body  163 . In this embodiment, a rib or brace structure  203  extends between the collar  183 , the upper surface  165  of the main body  163 , and the cylindrical arm  176 . In this alternate embodiment, the rib or brace structure  203  is cast as one member with the main body  163 , collar  183 , and cylindrical arm  176 . However, in additional embodiments, the brace structure  203  may be welded to the main body  163 , collar  183 , and cylindrical arm  176 , or may be connected by other means. In this embodiment, a rib or brace structure  205  extends between the upper surface  165  of the main body  163  and the cylindrical arm  176 . In this alternate embodiment, the rib or brace structure  205  is cast as one member with the main body  163  and with the cylindrical arm  176 . However, in additional embodiments, the brace structure  205  may be welded to the main body  163  and to the cylindrical arm  176 , or may be connected by other means. 
     In operation, the alternate embodiment packing nut lock and tool  161  is installed on the reciprocating pump  12  and engaged/disengaged with the packing nut  38  just as for the first embodiment of a packing nut lock  67  and also for the additional embodiment of a packing nut lock  121 . However, in the packing nut lock and tool  161  of this embodiment, the cylindrical arm  176  and the substantially rectangular engagement member  177  extend radially outward from the center of the packing bore  37  a distance that is greater than or equal to the distance from the center of the packing bore to the stay rod  15  (items illustrated in  FIG. 10  may be referred to). If the packing nut  38  begins to rotate relative to the housing  17 , the cylindrical arm  176  and the substantially rectangular engagement member  177  may make contact With the stay rod  15 , thereby preventing the packing nut lock and tool  161  from rotating relative to the housing  17 , and thus, also preventing the packing nut  38  from rotating any further relative to the housing  17 . As a result, the packing nut lock and tool  161  prevents the packing nut  38  from loosening and backing out of the packing bore  37 . 
     In operation, the alternate embodiment packing nut lock and tool  163  may also be utilized to tighten and/or loosen an item that incorporate holes or apertures on the outer diameter of the rim of the item. For example, generally referring to  FIG. 16 , a spanner (not shown) may be inserted into holes or apertures  40  on the outer diameter of the rim of the packing nut  38 , and the packing nut  38  may be tightened. However, referring to  FIG. 17 , to ensure that the packing nut  38  is securely tightened, the packing nut lock and tool  161  may be connected to the packing nut  38  by engaging the fixed cylindrical pin  171  and the center pin  185  with holes  40  in the packing nut  38 . As discussed With respect to the packing nut lock  67 , the center pin  185  is first retracted into the collar  183  using the handle  189  as the fixed cylindrical pin  171  is inserted into one of the holes  40  of the packing nut  38 . Once the fixed cylindrical pin  171  is positioned within one of the holes  40  of the packing nut  38 , the handle  189  of the center pin  185  is released, and the end portion  199  of the center pin  185  engages another hole  40  in the packing nut  38 , thereby securely connecting the packing nut lock and tool  161  to the packing nut  38 . Once the packing nut lock and tool  161  is connected to the packing nut  38 , a force may be applied to one of the planar contact surfaces  178 ,  179  of the substantially rectangular engagement member  177 . The force is applied at an angle substantially perpendicular to the planar contact surfaces  178 ,  179 , thus resulting in a force that causes the packing nut lock and tool  161  to rotate about the axis of the packing bore. For example, the force may be applied by an operator engaging the planar contact surfaces  178 ,  179  with a sledge hammer. The force can be applied to the contact surfaces  178 ,  179  until the packing nut lock and tool  161  rotates a desired amount, and thus, the packing nut  38  is either tightened or loosed to the operator&#39;s liking. Depending upon Whether the packing nut  38  is to be tightened or loosed, the force is applied to the corresponding contact surface  178 ,  179  of the packing nut lock and tool  161  to achieve the desired result, as illustrated in  FIG. 17  by the items F 1  and F 2  illustrating the direction of the force applied, and the corresponding directions of rotation, R 1  and R 2 . 
     The foregoing embodiment(s) described provide several operational advantages aimed at preventing backing off of the packing nut. When in place, the packing nut locks of the present disclosure maintain the necessary pressure between the plunger and the packing, and help to prevent the packing bore from leaking due to movement of the packing and backing off of the packing nut. The foregoing embodiments also provide a device and method for tightening and loosening a threaded nut in a threaded bore. 
     In the foregoing description of certain embodiments, specific terminology has been resorted to for the sake of clarity. However, the disclosure is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes other technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as “left” and right”, “front” and “rear”, “upward” and “downward” and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms. 
     In this specification, the word “comprising” is to be understood in its “open” sense, that is, in the sense of “including”, and thus not limited to its “closed” sense, that is the sense of “consisting only of”. A corresponding meaning is to be attributed to the corresponding words “comprise”, “comprised” and “comprises” where they appear. 
     In addition, the foregoing describes only some embodiments of the disclosure, and alterations, modifications, additions and/or changes can be made thereto without departing from the scope and spirit of the disclosed embodiments, the embodiments being illustrative and not restrictive. 
     Furthermore, disclosures have been described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the disclosure is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the disclosure(s). Also, the various embodiments described above may be implemented in conjunction with other embodiments, e.g., aspects of one embodiment may be combined with aspects of another embodiment to realize yet other embodiments. Further, each independent feature or component of any given assembly may constitute an additional embodiment.