MXPA99010303A - Adjustable pressestop for bom rods - Google Patents

Abstract

The present invention relates to a stuffing box for a cylindrical pump rod, comprising: a first housing adapted to be supported on a structure that includes a passage in which pressurized fluids are present and for which a assembled around the pump rod, to prevent the fluid under pressure from the conduit, the first housing includes a first hole forming a through hole for the rod, a second hole larger than the first hole, a first portion that is extends between the second hole and a transverse end wall of the first housing, a packing housing including a second portion that can be engaged with the first portion of the first housing, the packaging housing includes a central hole formed therein; of packaging placed in the hole, in the packing housing, and that can be manipulated so that it is in sealed coupling with the vari A packing collar that can be manipulated to engage with the packing assembly, substantially at one end thereof, a hub including a first part slidably placed in the hole in the packing housing, and which can be manipulated to engage with an opposite end of the packing assembly, to compress the packing assembly, said hub includes an end face exposed to the pressurized fluid from the conduit, to push the bushing and compress the packing assembly, a transverse flange and a second part extending from the flange, in sliding relation, with a hole formed in one of the housings and including the end face exposed to the pressurized fluid, and a means consisting of a spring that can be manipulated to engage with the flange to push the bushing into a forced coupling with the packing assembly to impose compression forces on the packing assembly

Description

ADJUSTABLE PRESSESTOP FOR PUMPING RODS FIELD OF THE INVENTION The present invention relates to adjustable packing glands and joint assemblies for cylindrical shafts or rods, particularly well pumping rods.

BACKGROUND OF THE INVENTION An old problem in the well pumping industry concerns providing an adequate seal around the reciprocating reciprocating pumping rod, or also called "polished" rod section, of an elongated pumping rod chain located towards the bottom of a drilling well. It is also found that this problem exists in relation to the rotary pumps located downstream of a drilling well and with the seals of the driving, rotating shafts for them. In shaft-driven, rod-driven pumping systems, the upper end of the elongated rod chain, which is connected to a pump drive, or also called a pump stand, is typically exposed to extreme environmental conditions. and must operate for long periods of time without being serviced, due to the remote location of many well pumps. However, the joint assembly surrounding the polished rod section of the pumping rod chain, which is commonly referred to as a stuffing box, is a critical element to prevent unwanted discharge of well fluids from the mouth. from the well, at the point of entry of the rod chain. Several efforts have been made to develop improvements in the pump rod packing glands. U.S. Patent Nos. 5,343,944; 5,538,080 and 5,636,688 and the co-pending U.S. patent application Serial No. 09 / 024,738 filed on February 17, 1998, all issued to Gray Bassinger, and U.S. Patent No. 5,803,169 issued September 8, 1998 to Gray Bassinger and Joseph L. Dalton, all assigned to the assignee of the present invention, represent improvements in the cable glands for well pump rods. However, certain applications for the well pump cable glands do not require self-aligning characteristics. The patents and patent application, mentioned above, may have, by design, a shorter service life, or, for various reasons, do not require the characteristics of the inventions of the patents and patent application referenced previously. In addition, virtually all applications for well pump glands require the simplicity of the gland design, reliable operation, no-service operation for long periods of time, and ease of adjustment and / or replacement or repair of stuffing box components, when find the person who is going to service the cable box. Accordingly, the characteristics that are desirable in the pump rod packing include automatic packing adjustment to compensate for wear, a suitable cavity for lubricant, to lubricate certain moving parts that are in the stuffing box, to provide pressure acting to compress the packing, which correspond or are proportional to the fluid pressure forces against which the gasket provides a gasket, ease of adjustment of the forces acting on the gasket, as provided by a packing collar, adjustable parts that are subject to wear by lateral deflection of the pump rod, ease of repair and adjustment, and a temporary seal or sealing feature to prevent fluids from flowing, under pressure, into the stuffing box during partial disassembly and repair, or during the replacement of the packaging.

The present invention provides the desired characteristics, mentioned above, as well as solves other problems in the art of adjustable glands for reciprocating movement pumping rods and the like.

SUMMARY OF THE INVENTION The present invention provides an improved, adjustable gland, particularly adapted to provide a joint for a shaft or pump rod, for deep well pumps and the like. In accordance with an important aspect of the present invention, there is provided a stuffing box for a reciprocating movement pumping rod, which includes a packing collar which can be adjusted as desired and can be adjusted by turns to compensate for the wear generated by the lateral deviation of the pump rod. According to another important aspect of the invention, a sliding bushing is placed in the stuffing box and acts against the packing, under the thrust of the elastic forces, as well as under the forces of fluid pressure, to compensate for wear in the packing, to increase the forces acting on the packing, in a manner proportional to the forces of the fluid pressure acting on the stuffing box and to extend the interval or time of operation, before the adjustment of the packing collar is required . In accordance with still another aspect of the invention, a stuffing box is provided which includes a housing supporting a sliding bushing which acts on the packing of the stuffing box, under the thrust of the elastic forces and the pressure forces of the fluid, and which is placed partially in a neutral pressure cavity that may contain a lubricant to lubricate the bushing and gaskets for it. The stuffing box packing is also placed between the packing adjustment bushing deflected by the elastic forces and fluid pressure forces, and a packing collar, and also functions as a bushing or bushing to minimize wear on the bushing collar and bushing. adjustment, due to any lateral deviation of the rod. In accordance with yet another aspect of the present invention, an adjustable cable gland for a well pump rod and the like is provided, wherein, during adjustment, repair or replacement of the stuffing box parts, an element known as sealing element or temporary seal, to prevent pressurized fluid from entering the stuffing box, from the hole in the well or from an associated wellhead structure. The present invention also provides a stuffing box and gasket assembly adapted for use with a rotating pump shaft or rod for driving a deep well pump, and similar equipment, and which enjoys the benefits and advantages of the invention, described above in the present. In addition, the improved gland for rotary shaft of the invention is advantageously provided with a refrigerant flow circuit. The present invention provides packing glands for pumping rods and the like, which meet the desirable characteristics mentioned hereinabove, and which solve the problems associated with the gland packing rods or pump shafts, in a manner hitherto not appreciated in the art. The technique. Those skilled in the art will recognize the superior features and advantages of the present invention, mentioned above, along with other important aspects thereof, by reading the following detailed description in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a longitudinal, central sectional view of a preferred embodiment of an adjustable cable gland according to the invention; Figure 2 is a sectional view, taken on line 2-2 of Figure 1; Figure 3 is a longitudinal, central sectional view of a first alternative embodiment of an adjustable stuffing box in accordance with the invention; Figure 4 is a top plan view, taken on line 4-4 of Figure 3; Figure 5 is a longitudinal, central sectional view of a second alternative embodiment of an adjustable stuffing box in accordance with the present invention; Figure 6 is a sectional, central, longitudinal view of a third alternative embodiment of an adjustable stuffing box in accordance with the invention; - * - Figure 7 is a sectional, central, longitudinal view of a fourth alternative embodiment of an adjustable stuffing box in accordance with the present invention; and Figure 8 is a longitudinal, central sectional view of an adjustable stuffing box and gasket assembly for a rotating shaft, in accordance with the invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES In the following description, similar parts are marked, through the description and the drawings, with the same reference numbers, respectively. The figures in the drawings are not necessarily to scale and certain features may be displayed on an exaggerated scale, or in a somewhat generalized form, for the sake of clarity and brevity. Referring to Figure 1, a cross-sectional, longitudinal, sectional view of an adjustable stuffing box and gasket assembly for a reciprocating reciprocating pumping rod, designated generally with the numeral 10, is illustrated. The stuffing box 10 is adapted for sealing the reciprocating movement cylindrical pumping rod section 12 against the release of pressurized fluid from a well structure, including a wellhead member 14, which has therein a conduit 16 in the well. which are present pressurized fluids. It is believed that the operating environment of a stuffing box for a reciprocating pump rod, including the so-called polished section 12 of the rod, is well known to those skilled in the art of reciprocating, well-stroke pumps, and it is believed that to carry out the present invention no additional description or illustration of the pumping system is necessary, including the drive mechanism to which the upper end of the polished rod 12 is connected. The stuffing box 10 includes a lower housing or coupler, 18, comprising an elongated, cylindrical tubular member having a reduced diameter section 20 which is externally threaded at 22 to be threadedly engaged to member 14 of the wellhead. The lower housing 18 includes a central hole 24 slightly larger than the diameter of the pumping rod 12 and which opens into a second larger hole 26, the holes 24 and 26 are interconnected by a frusto-conical wall portion 28 which is adapted to support a sealing, annular, flexible and compressible element 30, which when in a relaxed condition remains out of contact with the rod 12. The hole 26 includes an internally threaded portion 32 that extends upwards and up to a portion 34, slightly enlarged, which is intersected by an annular, annular seal, 36, placed in a suitable annular groove in the housing 18. The upper end of the lower housing 18 terminates in an end, annular, transverse wall , 38. Referring further to Figure 1, the stuffing box 10 includes an upper packing housing 40, comprising a generally cylindrical member that it has an end, transverse, lower, frustoconical shape 42, which can be coupled with the sealing element 30, as shown. The end wall 42 is delimited by an axial, central bore, 44, which extends upwards to the intersection with a transverse flange 46 which extends radially outwardly and is delimited by an enlarged diameter packing bore 48 extending axially. upwards, see Figure 1, to an upper, annular, transverse wall 50 of the packing housing. The upper, transverse wall 50 is formed on a cylindrical flange 52 of the housing 40 which is also bounded by a transverse flange 54 substantially parallel to the wall 50 and spaced therefrom. A cylindrical side wall 56 extends axially to an externally threaded portion 58 of the packing housing 40., and that threaded portion extends down to a cylindrical outer wall 60 of smaller diameter than the wall 56 and that the threaded portion 58 and intersects the frustoconical bottom wall 42. An annular groove 64 opens in the hole 44 and it supports therein a lip seal 66 which is adapted to seal a cavity 47 formed in part between the holes 44 and 48. The lip seal 66 is oriented to allow the fluid in the cavity 47 to escape from the cavity, under extreme pressure, downwardly and along the hole 44. The cavity 47 is adapted to accommodate therein an appropriate means consisting of a spring, comprising a cylindrical, wavy spring 49. The cavity 47 may be loaded as well. , at least partially, with a suitable lubricant. The cavity 47 is closed by a tubular packing hub 68, generally cylindrical, which includes a portion 70 of tubular pendant rod, which can slide axially in the hole 44 and an annular flange portion, upper, 72, which includes a circumferential groove for an O-ring 74 that can be coupled with the hole 48 to provide a seal between the cavity 47 and a packing assembly 78 of the rod. The bushing 68 has formed therein an axial, central hole 68a, and dimensioned to receive the rod 12 in sliding relation to the bushing. Packing assembly 78 includes a plurality of axially stacked, sectioned packing ring members 80, which may be formed from conventional packing materials for rods, known to those skilled in the art. For packaging members 80 a commercially available, long-lasting, woven packing material can be used. The packing assembly 78 is retained in the hole 48 between the tapered or inclined faces 71 and 83 of the respective axially slidable bushing 68, and a cylindrical packing collar 84 that extends up and out of the packing housing 40. The packing collar 84 is a tight fitting, axially sliding and rotatable, in the hole 48, and is provided with an annular groove suitable for retaining therein an O-ring 86 and which can be engaged with the hole 48 to provide a suitable gasket on top of the packing assembly 78 to prevent unwanted substances from flowing in any direction between the packing assembly and the environment external to the stuffing box 10. The packing collar 84 is provided with an externally threaded upper portion, of reduced diameter, 89, and of a central hole 90 which is a close enough but slidable assembly in relation to the pump rod 12. A flange member, in general ci lindric, 92, is threadedly connected to the packing collar 84, as shown, and can be coupled with the hexagonal, circumferentially spaced, hexagonal headed pins 96, two are shown, which are engaged by screwing them with the cooperating threaded holes. in the upper housing 40. Preferably four equally spaced bolts 96 are provided and project through the cooperating holes 93, two are shown, in the flange 92. When the stuffing box 10 is mounted to seal a reciprocating, reciprocating rod , a cylindrical ring, called a stacking ring, 99, is provided to rest on the heads 97 of the bolts 96, as shown in Figure 1. Referring also to Figure 2, the arrangement of the stuffing box 10 is such that the upper packing housing 40 can be engaged, by adjustment, with the lower housing 18 in the cooperating threads 32 and 58. A limit position of the housing 40 with rel The housing 18 is provided by a slotted separator or removable gauge ring, 100, formed of a polymeric material such as naylon, and having therein formed a radial slot 102, FIG. 2, to allow the ring to be flexed and slid in and out of the housing 40 to be placed between the upper transverse wall 38 of the housing 18 and the rim 54 on the housing 40. Typically the ring 100 can be removed, when desired, and the housing 40 can be rotated relative to the housing 18 to advance the bottom or bottom wall 42 against the packing element 30 to deflect the same and force it into engagement with the rod 12. This action will provide a temporary seal or "seal" of the hole 24 to prevent pressurized fluids from flowing through the hole between the housing 18 and the rod 12, upwards, when the 1 ^ cable gland has been partially disassembled, such as when replacing the packing assembly 78 or any of the 5 elements supported in the housing 40. The operation of the stuffing box 10 offers several advantages in the technique of cable glands for movement pumping rods. reciprocating The hub 68, ^ which slides axially in the hole 44 reacts to the elastic forces exerted by the corrugated spring 49 to exert compression on the packing assembly 78, as the packing wears. In addition, the pressure forces of the fluid, due to the pressurized fluid that is in the cavity 33 below the bushing 68 acting on the The transverse end wall 69 of the bushing also pushes the bushing 68 upwards, as seen in FIG. 1, to compress the packing assembly 78. As the fluid pressure in the conduit 16, in the hole 24 and in the cavity 33 act on the hub 68 with a force By increasing, the package 78 itself is further compressed by the bushing 68 to resist any leakage of fluid passing through the packing assembly, towards the outside of the stuffing box. In this way, the stuffing box 10 also self-adjusts as a result of changes in forces of pressure acting on the stuffing box, that is, more pressure forces due to fluid pressure, result in a greater sealing action or "compression" in the packaging assembly 78 and vice versa. At the same time, the spring 49 pushes the bushing 68 into engagement with the packing assembly 78 to keep the packing compressed as it wears. Of course, the packing collar 84 can be adjusted, as desired, by tightening or loosening the bolts 96 to effect axial movement of the packing collar relative to the housing 40. The cavity 47 can be filled, at least partially, with a lubricant to provide lubrication to the hub 68 for movement relative to the housing 40 and for the gaskets 66 and 74. If for some reason the volume of the cavity 47 has to be reduced to remove lubricant from the cavity, the gasket 66 will be biased to allow that this fluid escapes and prevent damage to the elements of the cable gland. In addition, the collar 84 can be adjusted by removing bolts 96 and rotating the collar and flange 92 at ninety degree intervals, to compensate for any wear of collar hole 90 due to any tendency of rod 12 to deviate laterally. In addition, the packing assembly 78 acts as a centering bushing to minimize wear on the bushing 68 and the packing collar 84. The deterioration of the toroidal joints 36, 74 and 86 will also not cause a failure of the basic operation of the stuffing box 10 and that the sealing element 30 will prevent fluid from leaking between the housings 18 and 40 and the packing assembly 78 will provide a seal between the conduit 16 and the exterior of the stuffing box 10 to prevent the flow of pressurized fluid between the packing and the hole 48 or between the packing and the rod 12. The repair and replacement of the stuffing box components, including the collar 84, the packing assembly 78, the bushing 68 and the gasket 66 can be done without removing the housing 40 from the housing 18 and, As mentioned above, the removal of the ring 100 allows the rotation of the housing 40 to tighten the sealing element 30 in engagement with the rod 12, to provide a temporary seal While the repair or replacement of the stuffing box components is being carried out. The thickness of the ring 100 is predetermined to be sufficient, such that, once the ring is removed from its working position, there is sufficient thread for coupling, to be used, between the housing 40 and the housing 18, so which housing 40 can be rotated to tighten the sealing element 30 to provide a protective seal, as described. The housing 40 is preferably provided with suitable hook-key receiving holes, not shown, circumferentially spaced at 90 degree intervals, for example, and intersecting the side wall 52b of the flange 52, so that it can be used , a hook wrench or similar tool, not shown, for rotating the housing 40 with respect to the housing 18, for deflecting the sealing element 30. Once the replacement or repair has been completed, the housing 40 is rotated in the opposite direction to allowing the sealing element 30 to loosen from the forced coupling with the rod 12. Accordingly, when preparations are made to repack the stuffing box 10, the aforementioned hook wrench is connected to the housing 40 and rotated briefly to release the compression on the ring 100 whereby the ring is removed, and the housing 40 is then turned in the opposite direction (in figure 2 it is observed in the clockwise for right threads) to deform the sealing element 30 and seal the housing 18 against the pressurized fluid found in the structure 14 of the wellhead. The bolts 96 can then be removed and the packing collar 84 can be moved up and along the rod 12 and moved aside while the packing elements 80 are replaced, as necessary. The lifting or adjusting bushing 68 can also be removed from the hole 48, if necessary, for repair or replacement of the bushing and / or the spring 49. The gaskets 66 and 74 can also be replaced if necessary. After a new hub 68 and / or packing 78 has been installed, the bolts 96 are conveniently tightened to compress the packing at least slightly, and the hook key, mentioned previously, engages the housing 40 to rotate the housing in a direction opposite to the movement of the hands of the clock, as seen in figure 2, to allow the sealing element 30 to loosen from the coupling with the shaft 12. The ring 100 is then reinstalled and the housing 40 is rotated again with the hook wrench, enough to lightly compress the ring and force the plug member 30 to effect a seal between the bottom or bottom wall 42 and the plug member 30 and between the wall face or portion 28 and the plug member. The dimensional relationships of the housings 18 and 40, the ring 100 and the sealing element 30 are provided for such action. Referring now to FIGS. 3 and 4, a first alternative embodiment of a stuffing box according to the invention is illustrated, and is designated generally with the numeral 110. The stuffing box 110 uses the housing 18, the sealing element 30, the ring 100, packing collar 84, and packing assembly 78, including individual packing members 80. Cable gland 84 also includes detachable flange 92 which is adapted to couple heads 97 of the four-bolt arrangement 96, see also figure 4. However, the stuffing box 110 is provided with a two-part upper packing housing, generally designated with the number 112, which is constructed similarly to the housing 40 and includes an upper flange portion of diameter enlarged 52a which is integrally formed with a cylindrical pendant portion 114 having an upper, tubular portion 116, adapted to be a slip assembly Adjustable in the hole 34 and provided with external threads 118 for the threaded coupling with the threads 32 of the housing 18, as indicated. The upper housing part 114 also includes a central hole 120 formed therein for receiving the packing assembly 78 and the packing collar 84 in the same manner as in the arrangement for the stuffing box 10. However, as indicated in 3, the packing housing 112 includes a lower end partcylindrical, separable, 122, which is provided with an end, bottom, frustoconical, end wall 124, which can be coupled to the sealing element 30. The end portion 122 of the housing includes a hole 126, a hole of reduced diameter 128 and an annular rim 130 formed therebetween. A cavity 132 similar to the cavity 33 is formed in part by the holes 126 and 128. The part 114 of the packing housing can be separated from the bottom 122 in the engaging threads 136a, 136b as indicated. The housing portion 114 also includes a stepped hole 121 that forms a cavity between a transverse end face 138 of the housing part 122 and a rim 117, FIG. 3. A cavity 140 is defined between the rim 117 and the transverse face 138. A tubular packing or fit, generally cylindrical, modified, 142, is slidably placed in the holes 120 and 126, and those holes are preferably of equal diameter. The bushing 142 includes an axial, central bore, 143, of such dimensions to receive the rod 12 by sliding therethrough. The hub 142 also includes an annular flange 144 formed thereon, which can be coupled with a corrugated spring 47 positioned between the flange and the transverse face 138. The flange 144 can also be manipulated to be engaged with the flange 117 to provide an upper limit for the travel of the bushing 142 in the packing cavity formed by the hole 120. Accordingly, the opposite portions 142a and 142b of the bushing, on the opposite sides of the flange 144, are preferably of equal diameter and are provided with suitable annular grooves formed therein, to receive the O-rings 74 adapted to be in a sealing engagement with the walls defining the holes 120 and 126. The bushing 142 includes the opposite end faces 147 and 149 which are also of an area substantially the same The stuffing box 110 also enjoys all the advantages of the stuffing box 10. The bushing 142 reacts to the forces exerted by the corrugated spring 47 to push the bushing and to enter in forced engagement with the packing assembly 78, and the bushing 142 also reacts to the forces of the pressurized fluid in the cavity 132 acting on the face 147 to also exert proportional compression forces on the packing assembly. A suitable lubricant can be placed in the cavity 140. No pressure is exerted on the lubricant due to movement of the bushing 142 in the cavity 140 when the gasket is compressed or begins to wear out, since the bushing portions 142a and 142b are of the same diameter, and the o-rings or rings and holes 120 and 126 are of the same diameter.

In this form, a neutral pressure in the cavity 140 allows the cavity to retain the aforementioned lubricating fluid for the O-rings or seals 74 and maintains the cavity and the holes 120 and 126 for the joints, free from the incursion of corrosive fluids. . After sufficient wear of the gasket 78 occurs, the flange 144 will engage the flange 117 and no further, upward stroke of the bushing 142 will occur. If the packing assembly 78 continues to wear out, the fluid leakage in the upper part of the packing collar 84 will indicate that the packing collar needs to be adjusted by tightening the bolts 96 which will effect the resetting of the bushing 142 back to a position, in general, as illustrated in figure 3. If the O-rings 74 fail, the stuffing box 110 will still work satisfactorily. Thanks to the arrangement of the hub 142 and the packing collar 84, these parts, in addition to the packing assembly 78, act as bearings to react against any deflection forces acting on the rod 12. If lateral wear occurs on the collar 84 the bolts 96 can be removed and the collar and flange 92 rotatably adjusted at 90 degree intervals, from time to time, to allow wear to occur in a uniform manner.

As shown in Figure 4, where the portions of the flange 92 are removed, the part 114 of the housing 114 is provided with at least two opposite holes 115 receiving a hook wrench, projecting radially, preferably separately as indicated, whereby the housing 112 can be engaged by a suitable key, not shown, and can be rotated to effect engagement of the sealing member 30 in the same manner as the housing 40, when desired, to service the gland 110, to replace the collar 84 or the packing assembly 78. Furthermore, the stuffing box 110 can be easily reconstructed by replacing the bushing 142, the packing assembly 78 and the packing collar 84, without replacing the housing 18 or the housing 112. Referring now to Figure 5, a second alternative embodiment of a stuffing box in accordance with the invention is illustrated, and is designated, in general, with the number 210. The saestope 210 is characterized by a modified lower housing 218 that includes an externally threaded portion, of reduced diameter, 220, having external threads 222 formed thereon, for coupling with the structure 14 of the wellhead. A first axial hole 224 is formed in the reduced diameter portion 220 and is slightly larger than the diameter of the rod 12. A second larger hole 226, coaxial with the hole 224, is formed in the receiving housing 218, in engagement by sliding therewith, an adjusting or lifting bushing 142, which includes the cylindrical portion 142b. An even larger hole 228 is also formed in the housing 218 coaxial with the hole 226 and a transverse flange 230 is formed between the holes 226 and 228. An internally threaded portion 232 extends from the hole 228 upwards and to a hole still larger 233 intersecting a transverse upper wall 234 of the housing 218, and that upper wall is substantially perpendicular to the central axis 235 of the holes 224, 226 and 228. The stuffing box 210 includes a single-member packing housing 240, which includes a generally cylindrical lower part 242 which is provided with external threads 244 which can be engaged with the threads 232 and a transverse end face 246 facing the rim 230 and which defines a cavity 248 for receiving the circumferential flange 144 of the bushing 142, as well as a bushing deviator spring 47, as illustrated. The packing housing 240 includes a longitudinal, central hole, 250, for receiving the packing assembly 78, the upper section 142a of the hub 142 in an adjustment without play, but with a slidable coupling therewith, and the packing collar 84 also in an adjustment without play but with a slidable coupling with the hole 250. The upper portion of the packing housing 240 includes a cylindrical flange of enlarged diameter 252 which includes circumferentially spaced holes 253 for receiving the bolts 96 and intersecting a transverse upper wall 255. A transverse flange 256 is formed between the upper portion 252 of the housing and the lower portion 242 of reduced diameter. An annular groove is formed in the reduced diameter portion 242, between the threads 244 and the flange 256 to receive an O-ring 260 which can be engaged with the side wall of the hole 233. Accordingly, the stuffing box 210 can be manipulated to providing a fluid-tight seal between the conduit 16 and the exterior of the stuffing box, substantially in the same manner as in the stuffing boxes 10 and 110. However, the stuffing box 210 is not provided with a sealing element between the end face 147 of the bushing and the hole 224. The bushing 142 is urged to compress the packing assembly 78 in the same manner as the other arrangements of the stuffing box, as a consequence of the pressurized fluid entering a cavity 261 formed by the housing 218 and the end face 147, transverse, of the bushing, such that the spring 47 and the fluid pressure forces acting on the end face 147 will push the bushing 142 to come into contact with the bushing. forced wrapping with the packing assembly 78. The stuffing box 210 can be adjusted to compress the packing assembly 78 in the same manner as in the other embodiments of the stuffing box described herein. The cavity 248 may also be filled with a suitable lubricant to lubricate the o-rings 74 and to allow the hub 142 to move freely between the holes 226 and 250 to maintain adequate compression, applied to the packing assembly 78. Once the flange 144 engages the transverse face 246, the packing must be adjusted by the adjustment of the collar 84. Furthermore, the bushing 142, the packing assembly 78 and the packing collar 84 react against the lateral deflection forces, if any. , which act on the rod 12. Referring now to Figure 6, another embodiment of a stuffing box and joint assembly is illustrated, in accordance with the invention, and is designated, generally, with the number 310. The stuffing box 310 includes a number of packing gland elements 110 illustrated in FIGS. 3 and 4 and is provided with a modified packing assembly 312 that includes a cylindrical portion of reduced diameter 314 ad adapted to be placed in a hole 34 in the housing, and includes external threads 316 that can be engaged with the threads 32. The packing housing 312 includes a cylindrical, ultiscalled hole, which includes a first portion 318 of the hole, a second portion 320 , of the bore, of reduced diameter, and a packing receiving hole 322, to receive the packing assembly 78 and the collar 84 in the same manner as the stuffing box 110. The lower, distal end of the packing housing 312 includes internal threads 324 that can be engaged with the threads 136 on an end portion 122a of the housing, which is essentially the same as the end portion 122 of the housing, for the packing housing 112. The packing housing 312 also includes an upper flange portion, cylindrical, elongate, 328, forming an annular, transverse flange, 330, with the reduced diameter portion 314 for coupling with the separating ring 100 interposed the flange portion 328 and the transverse end face 38 of the housing 18. The hole 320 is preferably of the same diameter as the hole 126 of the end portion 122a of the housing and the hole 318 forms a cavity 332 in which a coil spring 334. Spring 334 engages a circumferential flange 336 formed on a slidable bushing 338 having a transverse end face, lower, 340, a first cylindrical portion 338a, a second cylindrical portion 338b of the same diameter as the portion 338a and a third reduced diameter portion 338c placed by sliding in the hole 322. Suitable O-rings 74 are located on the portions 338a and 338b of the bushing and are in sealed engagement with holes 126 and 320, respectively. An O-ring 74a is located in a suitable annular groove on the reduced diameter portion 338c and is in sealed engagement with the hole 322. An upward tapered end face 342 of the bushing 338 can be coupling with the packing assembly 78 substantially in the same manner in which the bushing 112 of the stuffing box 110 can be coupled with the packing assembly of that stuffing box. A vented annular cavity 344 is formed between the bushing 338 and the packing housing 312 and is in communication with a conduit 346 that opens to the outside of the stuffing box 310 to prevent pressurized fluid from being trapped in the cavity and interfering with movement. from the bushing 338 upwards, to deflect and compress the packing assembly 78. The bushing 338 is provided with an internal hole 339 slightly larger than the diameter of the rod 12 to provide free sliding movement of the bushing, relative to the rod , as with the other bushings of the other packing glands described herein. The packing gland 310 functions substantially in the same manner as the stuffing box 110. Thanks to the supply of the coil spring 334, the effective working stroke of the hub 338 can be increased, as desired, to minimize the intervals at which it is required. of the adjustment of the packing collar 84. Furthermore, a multiplying effect of the pressing force can be provided, by means of the bushing 338 with a greater, transverse, end face 340, having an area greater than the end face 342, for which reason , for a determined fluid pressure, in the cavity 132, acting on the end face 340, a substantial compressive force can be exerted on the packing assembly 78. The packing housing 312 is provided with at least two counter holes 315, of hook key, formed therein to receive a hook wrench, suitable for effecting rotation of the packing housing relative to the lower housing 18 , to compress the sealing element 30, when desired. Referring now to Fig. 7, there is illustrated one embodiment of a stuffing box and joint assembly for a reciprocating reciprocating pumping rod 12, and is designated, generally, with the number 410. The packing gland assembly 410 is similar in some aspects to the stuffing box 210, and is provided with a lower, generally cylindrical, housing 412, including an externally threaded portion 414, adapted to be mounted on the wellbore member 14, in the same manner as the part corresponding to the stuffing box 210. The housing 412 includes a multiple step hole including a first hole portion 416, slightly larger than the diameter of the pump rod 12, and the enlarged hole 418 and still an additional enlarged hole 420 intersecting an extreme, transverse, upper face, 422, of the lower housing. The lower housing 412 includes a reduced diameter portion 423 having external threads 424 formed thereon, for threaded engagement with a generally cylindrical packing housing 426. The packing housing 426 includes an inner, lower, end portion. threaded, 428, with the internal threads 430 that can be engaged with the threads 424 to connect, so that they can be subsequently disconnected, the housings 412 and 426, one with the other. The packing housing 426 includes a cylindrical hole 434 packing receiver, which extends from a transverse, upper face 436, to an enlarged hole portion, 438, intersecting a transverse face 440 delimited by the threaded hole for the portion 428 of the lower housing. The housings 412 and 426 form an annular cavity 44 in which a spiral spring 446 is placed, and can be coupled with a circumferential flange 448 of a slidable bushing 450 substantially the same as the bushing 338 of the stuffing box 310. The bushing 450 includes a end, transverse, lower face, 452, which delimits a cavity 454f formed between the bushing 450 and the lower housing 412. The opposite, cylindrical, bushing portions 450a and 450b extend on the opposite sides of the flange 448, are of equal diameter and are adapted to support the o-rings 74, as shown. The bushing 450 includes an inner bore 451 slightly larger than the diameter of the rod 12 and a reduced diameter upper portion 456 slidably disposed in the bore 434 of the packing housing 426 and in sealed engagement therewith by an O-ring 74a . An annular cavity 460, formed by the bushing 450 and the packing housing 426, is vented to the outside of the stuffing box 410, through a conduit 462. The stuffing box 410 includes the advantages and characteristics of the stuffing box 310 which consist of the bushing 450 it has a larger cross-sectional area, on the end face 452, than on the end face 453, which can be coupled with the package 78 in such a way that a multiplier effect is provided by the fluid under pressure in the cavity 454 acting on the hub 452 for pushing it up and compressing the packing assembly 78. The lubricating fluid found in the cavity 444 is maintained at a "neutral" pressure thanks to the diameters of the hub portions 450a and 450b, which are the same, as well as, of course, the diameters of the holes 418 and 438. An effective, longer "working" stroke of the bushing 450 can be provided by the spiral spring 446 acting on the flange 448. for compressing the packing assembly 78. The packing collar 84 can be adjusted, when necessary, in the same manner as for the previous modes. Referring now to Figure 8, there is illustrated a stuffing box and joint assembly 510 for a rotating shaft, which enjoys the advantages of cable glands 110, 210, 310 and 410. However, the stuffing box 510 is adapted to provide a seal for a shaft or rotating rod 12r. The cable gland 510 is adapted to be mounted on an adapter part 14a of the wellhead, which has an internal conduit 16a in communication with the fluids produced by a rotary pump of the bottom of a drilling well, not shown, and connected to drive, shaft or rotating rod 12r. The cable gland 510 includes a generally cylindrical housing 512, having an internally threaded, downwardly directed hole 514 for coupling with an externally threaded, upwardly co-operating, 14b, part of the structure 14a of the wellhead , in a manner similar to the arrangement described in U.S. Patent No. 5,803,169. The housing 512 includes an upper end portion, of reduced diameter, 513, having external threads 515 formed thereon for engagement with a cylindrical cover 516 somewhat cup-like, having co-operating internal threads 518 coupled with the threads 515, a transverse upper wall portion 520 delimited by a face 522 and a hole 524 for articulation to a packing collar 526. The packing collar 526 includes an internal hole 528 for receiving the shaft or rod 12r and an annular flange 530 interposed in the portions of the collar, 526a and 526b, which are preferably of equal diameter. Packing collar 526 includes an end face, transverse, tapered or inclined532, which can be coupled with a packing assembly 78a having annular sealing rings 80a sectioned axially stacked around the shaft 12r, as shown, and which can be coupled with the shaft to substantially prevent the escape of fluid from the conduit 16a to the outside of the stuffing box 510. The o-rings 74g are supported on the packing collar 526 for the sealed coupling with the hole 524 and a hole 551 formed in a packing housing 550. The housing 512 includes a hole 536 of small diameter, of diameter slightly larger than the diameter of the axis 12r and intersecting a transverse flange 538 delimited by a larger hole 540. The hole 540 extends upwards to an annular, transverse flange, 542, interposed between the hole 540 and a even larger diameter hole 544. A third, substantially transverse, annular ridge 546 is positioned between the hole 544 and a hole 548 of still diameter the largest, from the housing 512, which extends upwards and to the upper, distal end portion, 513, and which opens toward the transverse end face 513a of the housing 512. The packing housing 550 comprises a reel-shaped member, in general cylindrical, placed in the hole 548 and retained therein by a releasable, retaining ring, 552, suitably positioned in an annular groove which is in the housing 512, as shown. The packing housing 550 includes a bell portion 554 between the opposing, annular flanges 556 and 558. The flanges 556 and 558 support the separate o-rings 74c in sealed engagement with the hole 548 in the housing. The packing housing 550 also includes an internal bore 551 for supporting the packing assembly 78a between the packing collar 526 and an axially slidable packing adjustment bore 560. The bushing 560 includes an internal bore 561 of diameter slightly larger than the diameter of the shaft 12r and a radially projecting circumferential flange 562, interposed in the hub portions, of equal diameter, 560a and 560b. The O-rings 74d are supported in suitable annular grooves, on the hub portions, 560a and 560b as shown in Figure 8, and are in sealed engagement with the side walls of the holes 540 and 551, respectively. A tapered or angled end face 563 of bushing 560 is in a position opposite to end face 565 and is brought into engagement with packing assembly 78a. A spring 568 of the corrugated or spiral type is placed in an annular cavity 570 formed by the lower housing 512, the packing housing 550 and the bushing 560, and can be engaged with the flange 562 to push the bushing 560 upwardly. and compressing the packing assembly 78a substantially in the same manner as for the packing adjustment bushings, the stuffing boxes 10, 110, 210, 310, and 410. Thanks to the same sealing diameters, portions 560a and 560b of the bushing, the cavity 570 remains at a neutral pressure and can be filled with a suitable lubricant, to lubricate the O-rings 74d and substantially prevent the migration of corrosive fluids through the stuffing box, to the packing assembly 78a, in particular. In addition, pressurized fluid entering the annular cavity 567 between the transverse face 538 of the housing 512 and the transverse end face 565 of the bushing 560 urges the bushing to compress the packing assembly 78a with a force proportional to the fluid pressure which is in conduit 16a. Another important advantage of the stuffing box 510 is the provision of means for cooling the packing assembly 78a during the operation of the stuffing box 510 due to the generation of heat by friction, which results from the coupling of the packing assembly 78a to the rotating shaft 12r. The packing housing 550 forms, in conjunction with the lower housing 512, an annular cavity or channel 571 that can be manipulated to be in communication with opposing holes 572 and 574 in housing 512. A third hole 576 in housing 512 is in communication with hole 514 and conduit 16a. A means consisting of a suitable conduit 580, interconnects the orifices 572 and 576 for driving the fluids produced, from a well, into and through the annular channel 571 which is in heat exchange relationship with the packing housing 550 to remove heat formation in packing assembly 78a. The fluid conducted through the annular channel 571 leaves the stuffing box 510 through a medium consisting of a suitable conduit 581, which can be connected to a line of the produced fluids, not shown. Accordingly, the fluid produced in a well to which the structure 14a of the wellhead is connected can be used to cool the stuffing box 510 in a unique manner. Alternatively, the orifice 576 can be properly connected and, as shown in Figure 8, an alternate cooling circuit can be provided that includes a medium consisting of a conduit 585 that is in communication with the holes 572 and 574 and that has a suitable pump 586 driven by a motor, and a heat exchanger 588 interposed therebetween to circulate a suitable refrigerant, continuously through the stuffing box 510. In addition, other sources of cooling fluid, not shown, can be connected to the orifice 572. for circulation through channel 571 and for removal of the stuffing box through hole 574.

The operation of the stuffing box 510 is similar in many respects to the cable glands 10, 110, 210, 310, and 410, because the sliding bushing 560 responds to the thrust of the spring 568 and to the pressurized fluid forces acting on the face 565 for compressing the packing assembly 78a and providing a substantially fluid-tight seal for the rotating shaft 12r. The packing assembly can be replaced, when needed, by removing the cover 516 from the housing and the packing collar 526 and moving these members upwardly on the shaft 12r, far enough to have access to the packaging assembly 78a, as necessary, and then reconnecting the packing collar and the cap 516 to the lower housing 512. The packing housing 550 and the hub 560 can also be removed from the upper end 513 of the housing 512 without removing the housing from the structure 14a from the wellhead . The cable glands 10, 110, 210, 310, 410, and 510 can be constructed using conventional engineering practices, known to those skilled in the art. The cable glands 10, 110, 210, 310, 410, and 510 can also use conventional engineering materials, different from those described herein, for the different components described and shown. The spring or springs 47 may be configured other than that of the indicated corrugated springs. In addition, the assembly, disassembly and adjustment of the stuffing boxes 10, 110, 210, 310, 410, and 510 and the use of the stuffing boxes for other, but similar, applications of joints for rotating rods or reciprocating movement, is found, it is believed, within the competence of a person of ordinary skill in the art, based on the foregoing description and the features illustrated in the figures of the drawings. Although previously described herein, preferred embodiments of the invention have been described, those skilled in the art will also recognize that various substitutions or modifications to the invention can be made without departing from the scope and spirit of the appended claims.

Claims (21)

NOVELTY OF THE INVENTION Having described the foregoing invention, it is considered as a novelty, and therefore, the content of the following is claimed as property: CLAIMS

1. A stuffing box for a cylindrical pump rod and similar parts, comprising: a first housing adapted to be supported on a structure including a conduit in which pressurized fluids are present and for which a seal is to be formed around the pump rod, to prevent the pressurized fluid from escaping from the conduit, the first housing includes a first hole forming a through hole for the rod, a second hole larger than the first hole, a first portion extending between the second hole and a transverse end wall of the first housing; a packing housing including a second portion that can be coupled with the first portion of the first housing, the packaging housing includes a central hole formed therein; a packing assembly placed in the hole in the packing housing, and which can be manipulated to be in sealed engagement with the rod; a packing collar that can be manipulated to mate with the packaging assembly, substantially at one end thereof; and, a bushing including a first part slidably positioned in the hole in the packing housing, and which can be manipulated to engage with an opposite end of the packaging assembly to compress the packaging assembly.

2. A cable gland according to claim 1, characterized in that the bushing includes an end face exposed to the fluid under pressure from the conduit, to push the bushing and compress the packing assembly.

3. The stuffing box according to claim 2, characterized in that it includes a means consisting of a spring that can be manipulated to engage with the bushing and push the bushing to impose compressive forces on the packing assembly.

4. The stuffing box according to claim 3, characterized in that the bushing includes a transverse flange coupled with the means consisting of a spring, for pushing the bushing and causing it to enter a forced coupling with the packing assembly.

5. The stuffing box according to claim 4, characterized in that the bushing includes a second part extending from the rim, in sliding relation, with a hole formed in one of the housings and including the end face exposed to the pressurized fluid.

6. The stuffing box according to claim 5, characterized in that it includes a cavity formed at least in part by one of the housings and that retains therein the means consisting of a spring.

7. The stuffing box according to claim 6, characterized in that the first part and the second part of the bushing are substantially of equal diameter, the cavity is adapted to receive a lubricating fluid therein and the cavity remains at a substantially constant pressure in response to the movement of the bushing with respect to the cavity, to prevent forced displacement of the lubricant from the cavity.

8. The stuffing box according to claim 6, characterized in that the bushing includes a circumferential flange formed thereon and defines the transverse flange for coupling with the means consisting of a spring.

9. The stuffing box according to claim 6, characterized in that the packing housing includes a separable part for retaining the bushing in the packing housing, and the packing housing and the separable part define the cavity.

10. The packing gland according to claim 5, characterized in that the packing housing includes a stepped hole for receiving the bushing and defining a cavity between the bushing and the packing housing, for retaining therein the medium consisting of a spring and acting on the bushing

11. The stuffing box according to claim 6, characterized in that the second hole which is in the first housing includes a portion for receiving the bushing in a slidable relation therein, and a transverse rib in the first housing for supporting the means consisting of a spring, for coupling with the bushing.

12. The stuffing box according to claim 1, characterized in that it includes a separating ring, removable, interposed between the housings, to maintain the housings in a predetermined position relation, one in relation to the other.

13. The cable gland according to claim 12, characterized in that it includes a seg element, annular, placed in the first housing and that can be coupled with the packing housing to be diverted to a seg coupling with the rod, in response to the movement of the seal. packaging accommodation, in relation to the first accommodation.

14. The stuffing box according to claim 13, characterized in that the first portion of the first housing and the second portion of the second packing housing include on the same, cooperating threads respectively, to secure the housings with each other and provide rotation of the housing of the housing. packing relative to the first housing, to deflect the seg element and make it enter seg engagement with the rod.

15. The packing gland 14, characterized in that the packing housing includes an upper flange part that can be coupled with the ring and the first housing includes a transverse end wall that can be coupled with the ring to limit the degree of threaded engagement of the housing of the housing. packaging, with the first accommodation.

16. The stuffing box according to claim 14, characterized in that it includes at least one hole for receiving a wrench, formed in the packing housing to receive a means consisting of a wrench, to rotate the packing housing in relation to the first accommodation.

17. The stuffing box according to claim 1, characterized in that it includes a transverse flange part connected to the packing collar and separate circumferentially fastening means, which can be coupled with the flange part and with the packing housing, to retain the collar Packaging connected to the packing housing, the packing collar and the flange portion can be adjusted by turns, with respect to the packing housing, to predetermined positions to rotationally locate the packing collar, to distribute the lateral wear on it.

18. The stuffing box according to claim 1, characterized in that it includes an annular cavity formed between the packing housing and the first housing, and in communication with a medium consisting of a conduit, for driving a cooling fluid through the cavity and cooling the packaging assembly.

19. The cable gland according to claim 18, characterized in that the means consisting of a conduit is in communication with a pressurized fluid communicated thereto from the structure on which the first housing is adapted to be supported.

20. A cable gland according to claim 18, characterized in that the means consisting of a conduit comprises a closed circuit conduit connected to an inlet orifice and an outlet orifice in the first housing, respectively, and in communication with the annular cavity, and the means consisting of a duct includes a pump and an interposed heat exchanger to circulate coolant through the annular cavity and cool the packing assembly.

21. The stuffing box according to claim 1, characterized in that it includes a cover member connected, so that it can be removed, to the first housing, to retain the packing collar in functional coupling with the packaging assembly. SUMMARY OF THE INVENTION Cable glands for use with reciprocating or reciprocating pump rods, for pumps in the bottom of a drilling well, include a lower housing adapted to be mounted over the mouth of a well and provided with internal holes to receive the pump rod and a packing housing coupled with the lower housing and including a central hole for receiving a packing assembly and a packing collar. The packing collar may include an annular flange for supporting circumferentially spaced bolts that can be engaged with cooperating holes in the packing housing to adjust compression on the package, and to provide adjustment by rotation of the collar to minimize wear not uniform. An axially slidable bushing, mounted in the packing housing or lower housing, can be coupled to the opposite end of the packaging assembly and is provided with an annular, transverse flange, coupled by a biasing spring, for exerting compressive forces on the packaging assembly. The bushing includes an extreme, transverse face, exposed to the pressurized fluid to also push the bushing and bring it into engagement with the packing assembly. An annular cavity for the bushing deflection spring can be filled with a lubricant, at neutral pressure, provided by the equal diameter portions of the bushing. A sealing element, annular, may be placed in the lower housing and may be coupled by the packing housing to form a temporary joint during repair or replacement of the packing assembly and / or packing collar. The most representative figure of the invention is number 1.