US 2564912 A
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Description (OCR text may contain errors)
Aug. 21, 1951 w. H. MOKISSICK STUFFING BOX 2 Sheets-Sheet 1 Filed Nov. 28, 1947 .1 Z g &
4 .I 7 v ov mm H m m 3 o W M William H. M /f/ss/c/r 1951 w. H. MCKISSICK 2,564,912
STUFFING BOX Filed Nov. 28, 1947 2 Sheets-Sheet 2 0 6 William H. M /r/SS/Ck Patented Aug. 21, 1951 UNITED. STATES PATENT OFFICE STUFFING BOX William H. McKissick, Tulsa, Okla.
Application November 28, 1947, Serial No. 788,488
This invention relates to new and useful improvements in stuffing boxes.
One object of the invention is to provide an improved stuffing box for use with polish rods and of such construction that more efficient and economical results are obtained.
An important object of the invention is to provide an improved stufiing box having a floating packing member mounted therein so as to undergo limited movement,- with a polish rod while maintaining a fluid-tight seal therearound.
A particular object of the invention is to provide an improved stufling box wherein its packing is free to flex upon lateral movement of the polish rod and is maintained in position by a floating gland which permits such flexing so as to preserve the fluid seal of the packing.
Another object of the invention is to provide an improved stuiiing box having a conical packing held in position by a complementary gland, a portion of the packing being free to flex independently of the gland to compensate for irregularities in the polish 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 drawings,
wherein examples of the invention are shown,
and wherein Fig. 1 is a transverse, vertical, sectional view of a stufiing box constructed in accordance with the invention,
Fig. 2 is a plan view of the stuiiing box,
Fig. 3 is a perspective view, partly in section, of the packing of the stufling box,
Fig. 4 is a view, partly in elevation and partly in section, of a modified form of stuffing box and packing,
Fig. 5 is a View, similar to Fig. l, of another modification, and
Fig. 6 is a horizontal, cross-sectional view, taken on the line 6--6 of Fig. 5.
In the drawings, the numeral l designates a stufling box housing or body having external screw threads I l and a depending, reduced neck or shank portion 12 which is externally screwthreaded at I 3 for connection with a well head or conductor (not shown). The neck I2 is in axial alinement with the body l0 and its bore is much smaller than the bore of said body so as to provide an annular, radial shoulder or seat M at their juncture or inner-section. A polish rod I is adapted to extend axially through the bore of the body and its neck l2 and a follower cap or head l6, having an internally screw-threaded skirt or depending flange I1, is threaded upon the upper end of said body. The top of the cap I6 is fiat and has an axial opening l8 therein for accommodating the polish rod 15. If desired, the upper marginal edge portion of the opening l8 may be bevelled as shown by the numeral I9. A transverse partition 28] extends across the upper portion of the cap to provide an oil reservoir or chamber 2| thereabove. The partition 20 has a central opening 22 in alinement with the cap opening l8 and these openings as well as the bore of the neck I2 are of greater diameter than the polish rod to permit limited lateral movement of said rod relative to the stufiing box. For rotating the cap so as to engage and disengage the same with the body, a suitable hand wheel 23 surrounds said cap and is secured thereto by a plurality of spokes 24 (Fig. 2)
A packing assembly including a frusto or substantially conical packing member 25, or rubber or other suitable material, is confined within the body by a complementary, telescoping gland 26. As is most clearly shown in Fig. 3, the packing member 25 has an axial bore 27 for snugly receiving the polish rod, whereby oil and grease is stripped from said rod and the upward passage of fluid and gases is prevented. A plurality of annular grooves or recesses 28 are formed in the bore 27 in spaced relation for trapping oil so as to lubricate the rod as it is drawn through the packing member. At the larger or lower end of the packing member, the bore is enlarged by being flared or tapered outwardly as shown by the numeral 29. Thisend of the packing member is of substantially the same diameter as the bore of the body and is seated upon the shoulder [4 with its outer periphery engaging the wall of said body. The gland 26 encircles and confines the upper or smaller portion of said member and an enlarged, radial collar or flange 30 is provided at its smaller or upper end for snugly engaging the polish rod and bearing against the underside of the cap partition 20, whereby the packing member is clamped or confined between said partition and the shoulder M. It is pointed out that the internal diameter of the collar 30 is less than the diameters of the bore of the neck l2 and the openings [8 and 22, whereby said collar and the gland move laterally with the rod relative to the body. If desired, the larger or lower extremity of the gland may be turned or flared outwardly to provide a radial lip 3| which facilitates telescoping of said gland over the packing member and prevents cutting of said member upon flexing of the latter.
By screwing down the cap, the conical or tapered gland 26 is forced downwardly over the substantially conical or tapered packing member 22 until the lower portion of said gland surrounds or telescopes the upper portion of said member. As has been explained, the bore 21 of the packing member snugly engages the polish rod so as to strip the same of oil and grease and prevent the upward passage of fluid and gases. Due to the enlarged diameters of the openings l8 and 22 and the bore of the neck l2, the rod may undergo limited lateral movement and the gland as well as the upper portion or the packing member moves therewith. This movement is permitted by the flexing of the packing member and the floating arrangement or connection of its upper portion. Since the lower portion of the packing member is unconfined, except by the body it, the bore of said member is maintained in snug engagement with the rod to assure a fluid-tight seal. Jihe enlargement 29 of the bore increases the flexibility of the packing member without impairing its sealing qualities. Manifestly, the packing member and gland function as a unit or assembly for positively sealing off around a polish rod.
A modified form of the invention is shown in Fig. 4 and includes a similar stufling box housing or body 32 having a follower cap or head 3-, screw-threaded thereupon by means or a hand wheel 34. The body 32 has an externally screw-threaded neck 35 and an annular shoulder or seat 36, while a transverse partition 3? and an oil reservoir or chamber 38 are formed in the cap. Axial openings 35 and 39, for receiving the polish rod l5 and similar to the openings I8 and 22, are formed in the top of the cap and its partition 31, respectively. Although the packing assembly of the first form could be employed, a modified assembly is illustrated and includes a packing member dl and gland which are tapered or substantially conical and which are preferably inverted. An axial bore 43, having a plurality of spaced, annular grooves or recesses 45, is formed in the packing member ii for snugly engaging the polish rod it. The upper or larger end of the packing member has its extremity reduced in diameter to provide an annular shoulder 45 for receiving an angular reinforcing or confining ring 4'6. The latter bears against the underside of the cap partition ill whereby screwing down of the cap forces the smaller or lower end of the packing member into the upper or larger end of the gland 52. An enlarged, radial collar or flange til is formed on the lower or smaller end of the gland for resting upon the shoulder 36 and supporting the packing member. Since the collar 4! snugly engages the polish rod, said collar closes the bore of the neck 35 to prevent small particles of the packing material from falling into the well head or conductor (not shown). This packing assembly is substantially the same as the first form and functions in a substantially identical manner.
In Figs. 5 and 6, another form of the invention shown and includes a similar stuflihg box housing or body 18 having a follower cap or head s screw-threaded thereupon by means of a hand wheel Ell. An annular shoulder or seat 5i is formed within the lower portion of the body t8 and the bore of the body is reduced in diameter immediately above the shoulder as shown by the numeral 52. The body has an externally screw-threaded neck 53 for connecting the same to a well head or conductor (not shown). An axial opening similar to the openings i8 and oe, is formed in the top of the cap 49 for receiving the polish rod it). The interiors of the body and cap are unobstructed and a seat 55, similar to the seat 52, is formed in the top of said cap immediately below the opening 54. This stufiing box has still another form of packing assembly and includes a pair of frusto-conical packing members 56 having a complementary, coacting gland ill. Each packing member has an axial bore with spaced, annular grooves or recesses so formed therein. At the larger or outer end of its packing member, each bore 55 is enlarged by being flared or, tapered outwardly as shown by the numeral 56. The gland 51 is interposed between the packing members 55 with the smaller or inner ends of said members telescoping or engaging in the end portions of said gland. Thus, the gland is of substantially hourglass shape, having enlarged, outwardly-flared end portions iii and a medial portion 62 which of larger diameter than the polish rod and spaced therefrom to provide an oil reservoir or chamber '63 between the packing members. The larger or lower end of the lower member rests upon the shoulder 5i within the seat 52 of the body while the larger or upper end of the upper member engages and is confined within the seat 55 of the cap Due to this arrangement, the gland is confined between the packing members and the elements of the pack ing assembly coact to maintain each other in position. For lubricating the polish rod, an annular, radial trough-like member or flange 65 encircles the medial portion 62 of the gland and communicates with the chamber 53 by means of a plurality of ports The flange Gd preferably has an upwardly-directed, peripheral lip and is adapted to catch and collect oil from an angular drip port or duct El formed in the cap 9. An elbow or fitting SS is screw-threaded in the outer end of the duct 5?, whereby a dripoiler (not shown) or other similar device may be connected thereto. Obviously, a packing assembly of this construction functions in substantially the same manner as the other packing assemblies.
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:
l. A stuffing box for polish rods including, a body, a cap adjustably mounted on the body, the cap and body having axial openings for receiving a polish red, the openings being of larger diameter than the rod to permit lateral movement thereof, a packing member having its bore snugly engaging the rod within said body, and a gland surrounding one end portion of the packing member so as to confine the end portion and maintain said member in position, the gland and the confined end portion of said member being of a diameter less than the internal diameter of said body so as to be spaced therefrom and movable laterally with the rod relative to said body upon flexing of said member, the member having its bore enlarged at its end portion opposite its confined end portion so as to increase the flexibility of said member.
2. A stufiing box for polish rods including, a body, a cap adjustably mounted on the body, said body and cap having enlarged openings for receiving a polish rod and permitting lateral movement of the rod therein, a substantially conical elastic packing member snugly engaging the rod Within said body, and a complementary gland telescoping the smaller end portion of the packing member and engaging the rod, the gland and the smaller end portion of said member being of a diameter less than the internal diameter of said body so as to be spaced therefrom and movable laterally with the rod relative to said body, the remainder of said the gland and capable of flexing to permit lateral movement of said rod and gland.
3. A stuff ng box as set forth in claim 2 wherein the bore of the packing member is enlarged at its larger end to increase the flexibility thereof.
4. A stuffing box as set forth in claim 2 wherein the larger end of the packing member is provided with reinforcing means.
packing member being free of 5. A stuffing box as set forth in claim 2 wherein a pair of packing members surround the polish rod within the body and are held in spaced relation by the gland, said gland being interposed therebetween and telescoping over the smaller ends of both of the packing members.
WILLIAM H. MoKISSICK.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 134,955 Welch Jan. 14, 1873 141,052 Heston July 22, 1873 911,891 Lyon Feb. 9, 1909 1,256,899 Heggem Feb. 19, 1918 1,735,193 Wilson Nov. 12, 1929 1,799,335 Waddell Apr. 7, 1931 1,813,308 McKissick July 7, 1931 1,832,252 Simmons Nov. 17, 1931 1,877,696 Shellack et a1. Sept. 13, 1932