US2854260A

US2854260A - Packing element for wire link and polished rod wipers

Info

Publication number: US2854260A
Application number: US480415A
Authority: US
Inventors: Edward B Skinner
Original assignee: Skinner Brothers Rubber Co
Current assignee: Skinner Brothers Rubber Co
Priority date: 1955-01-07
Filing date: 1955-01-07
Publication date: 1958-09-30
Anticipated expiration: 1975-09-30

Description

Sept 3% 3% E. a. QKRNNER PACKING ELEMENT FOR WIRE! LINE AND POLISHED ROD WIPERS I Filed Jan. 7, 1955 I INVENTOR Edward kl fifii jw J J ATTORNEYS Fig. 5

United States Paten PACKING ELEMENT FOR WIRE LINK AND POLISHED ROD WIPERS Edward B. Skinner, Wichita Falls, Tex., assignor to Skinner Brothers Rubber Company, Dallas, Tern, a partnership Application January 7, 1955, Serial No. 480,415

3 Claims. (Cl. 28616) This invention relates to new and useful improvements in packing elements for wire line and polished rod wipers as well as other wipers.

Oil savers and wipers of the type shown in United States Letters Patent No. 1,858,882 are in common use for stripping well fluids from polished rods and wire lines being withdrawn from well bores and include a pair of opposed packing elements slidably mounted in a stufiing box and held in engagement with a rod or wire line extending through the box by adjustable followers. Since the packing elements are subject to rather rapid wear, the same are in the form of elongated blocks and are adapted to be moved inwardly by the followers. In conventional wipers, the wear has tended to concentrate on one side or the other of the packing elements due to the lateral movement of the line or rod whereby one side of said elements is completely worn away and fails to function. As a result, the packing elements become inoperative and require frequent replacement without being completely used up.

Therefore, one object of the invention is to provide an improved packing element for a wire line or polished rod or other wiper of such construction that the wear of the element is centralized so as to prevent uneven wear and premature failure thereof.

Another object of the invention is to provide improved packing elements for a wiper, of the character described, wherein the wear surface of each element is cut longitudinally of the wire line or polished rod to cause wear of the central portions of the elements and assure even distribution of the material of said elements.

A particular object of the invention is to provide an improved packing element for a wiper, of the character described, wherein the wear surface and major portion of the element is slit longitudinally of the line or rod to confine the majority of the Wear to the central longitudinal portion of said element and reduce uneven lateral wear to a minimum.

A further object of the invention is to provide an improved packing element for a wire line or polished rod wiper, of the character described which will assist in guiding the line or rod so as to reduce the strain and wear of the guide bushings of the wiper and thereby the strain and wear on said wire line or polished rod.

A construction designed to carry out the invention will be hereinafter described together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawing, wherein examples of the invention are shown, and wherein:

Fig. l is a transverse, vertical, sectional view of a wire line wiper having packing elements constructed in accordance with the invention,

Fig. 2 is a perspective view of one of the packing elements,

Fig. 3 is a horizontal, cross-sectional view, taken on the line 33 of Fig. 1,

Fig. 4 is a perspective view of a modified packing element for a polished rod wiper, and

Fig. 5 is a longitudinal, sectional view, partly in elevation, of the modified packing element.

In the drawing, the numeral 10 designates the conventional stufiing box or housing of a wire line wiper which is shown in detail in the aforesaid Patent No. 1,858,882. Since oil savers or polished rod wipers are very similar to wire line wipers, the former has not been illustrated. The box is rectangular, having one transverse dimension greater than the other and exceeding the height of said box, and has an axial, depending, screw-threaded nipple 11 for connection with a well pipe or tubing (not shown). A thrust plate 12 closes each transverse end of the box and is removably supported by engagement with an underlying groove 13 formed in the lower portion of said box and an overhanging pivoted latch 14. Each plate 12 has a screw 15 threaded therethrough for supporting a follower 16 within each end portion of the box for adjustable movement inwardly and outwardly of the upright axis of said box. A lever 17 is carried by the outer end of each screw 15 to impart rotation thereto and reciprocal movement to the follower 16.

A pair of alined, opposed packing elements 18, of rubber or other elastic or resilient material, are confined within the end portions of the stufiing box for engaging and sealing off around a wire line or other cylindrical member extending through said box and its nipple 11, as shown by the broken lines 19. Each element is generally rectangular and is in the form of a body or block of relatively narrow width compared to its height and length, which latter dimensions may be substantially equal. Of course, the elements 18 are disposed uprightly and the dimensions of each element conform substantially to the internal contour of the box. As shown most clearly in Figs. 2 and 3, a semi-cylindrical groove or recess 20 extends throughout the length of the upright inner face of each element and coacts with the groove of the other element to encircle the wire line. The longitudinal groove is disposed medially of the lateral margins or sides of each element to provide coextensive lips 21 on each side thereof. It is customary to provide a complementary 1ongitudinal protuberance or tongue 22 on the outer end of each element for mating engagement with the groove 20, whereby additional packing elements inserted in the ends of the box upon Wear of the original elements will conform to the latter. The followers 16 conform to the outer ends of the elements and are adjusted by their screws 15 so as to urge the lips 21 of said elements into tight engagement with the grooves 29 snugly engaging the wire line for sealing off therearound and stripping oil or well fluids therefrom upon withdrawal of said line.

It has been found that packing elements, of the character described hereinbefore, have a tendency to wear unevenly toward one side or the other and one lip 21 has been completely worn away in manyinstances. As a result, the elements fail to seal off around the wire line and to strip sutficient oil therefrom so as to necessitate frequent replacement of said elements. Unevenly worn elements rapidly fail to provide adequate stripping action and must be completely removed from the stuffing box. Manifestly, this is laborious and time-consuming as well as more difficult than the mere insertion of additional elements in the ends of the stuiling box. In order to prevent un ven wear of the packing elements 18, a central, longitudinal slit 23 extends throughout the length of the inner face and groove of each element and is relatively deep so as to extend an appreciable distance outwardly of the element beyond said groove. Preferably, the slit terminates adjacent the outer end of the element and is spaced a sufficient distance from said outer end to prevent tearing of said element. By medially slitting the elements longitudinally of their grooves, said elements are partialwith guide bushings 24 and 25, of relatively soft metal,

to prevent abrasion and marring of the cylindrical member 19, particularly a polished rod, extending through said box. As shown in Fig. 1, the bushings usually are mounted immediately above and below the packing elements in axial alinement with the bore formed by the grooves 20 of said elements. Manifestly, the slits 23 of the elements in centering the wear ofsaid elements reduce strain and wear on the bushings and thereby on the rod, line or other member.

A packing element 28 for an oil saver or polished rod wiper is shown in Figs. 4 and 5 and is of similar contour and dimensions. Due to its similarity to the wire line wiper, the oil sa 'er or polished rod wiper is not illustrated. A pair of the elements 28 are adapted to coact in the same manner as the elements 18 andeach element includes, a similar groove 36, lips 31, tongue 32 and slit 33. ,In order to accommodate the larger diameter of the polished rod not shown), the elements 28 are of greater width than the-elements 13 and the grooves 30 are of greater diameter than the grooves 29; however, the stripping action of said elements is substantially identical. If desired, either one of the elements and preferably the elements 28 may be provided with a plurality of cylindrical, parallel openings or

recesses

27 and 29 in their inner faces for trapping oil or well fluids to lubricate the grooves and reduce wear thereof as well as to increase the flexibility of the inner end portions of. said elements. The openings extend longitudinally of each element from its groove and at a right angle to the longitudinal axis of thegroove. The openlugs 27 may be disposed adjacent the four corners of each element at a tangent to the groove, while the openings 29 may have their axes coinciding with the slit 33.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

1. A packing element for a stufling box wherein a pair of packing elements are mounted in opposed relationship for-inward movement to seal off around a member extending through the stutfing box, the element including a block of elastic material havinganinner end adapted to engage the inner end of the opposed element, the block having a groove in its inner end substantially complementary to and extending longitudinally of the member, said block having a slit coextensive with the groove and extending therefrom toward the outer end of said block whereby the majority of the wear of said groove is confined to the direction of the slit upon inward movement ofsaid block.

2. A packing element as set forth in claim 1 wherein the groove and slitare disposed medially of the lateral margins of the block so as to confine the wear to the medial portion of said block.

3. A packing element as set forth in claim 1 wherein the slit is relatively deep and terminates in the outer end portion of the block.

References Cited in the file of this patent UNITED STATES PATENTS 1,848,500 Standlee Mar. 8, 1932 1,858,882 Cole May 17, 1932 1,898,311 Pettitt Feb. 21, 1933 1,930,361 Kilmer Oct. 10, 1933 2,144,403 Davidson Jan. 17, 1939 2,351,343 Kelley June 13, 1944 2,746,709 Minor May 22, 1956