US2972471A

US2972471A - Oil sealed drilling bumper sub

Info

Publication number: US2972471A
Application number: US621169A
Authority: US
Inventors: Ross A Mcclintock; Raymond E Thompson
Original assignee: Shaffer Tool Works
Current assignee: Shaffer Tool Works
Priority date: 1956-11-08
Filing date: 1956-11-08
Publication date: 1961-02-21
Anticipated expiration: 1978-02-21

Description

1961 R. A. MOCLINTOCK EI'AL 2,972,471

011. SEALED DRILLING BUMPER SUB Filed Nov. 8, 1956 Fig/B 67 akk 29- R055 A. MCCL/NTOOK, RAYMOND THWPSGV, INVENTORS United States Patent 2,972,471 OIL SEALED DRILLING BUMPER SUB Ross A. McCliutock, Orange, and Raymond E. 'lholnpson, Fullerton, Calif., assignors to Shatter Tool Works, Brea, Calif a corporation of California Filed Nov. 8, 1956, Ser. No. 621,169 2 Claims. (Cl. 175-293) This invention relates generally to well drilling equipent or apparatus and relates more particularly to improvements in bumper subs and the like.

While the invention has particular utility in connection with oil well drilling equipment, and is herein shown and described in connection therewith, it is to be understood that its utility is not confined thereto.

In the drilling of oil wells, drilling bumper subs are used in the drilling string as is well known in the art. Difliculty has been encountered in keeping abrasives such as mud, sand and eorroding chemicals and the like from the operating mechanism of the bumper sub, and particular problems have been encountered in offshore or underwater drilling where it is necessary to keep the sea water from getting in to the operating mechanism.

It is, therefore, an object of the present invention to provide a bumper sub having means for sealing out abrasive and corrosive matter from the operating mechanism of said sub.

It is still another object of the invention to provide a device of this character that is completely oil-sealed.

Still another object of the invention is to provide a device of this character wherein the packing elements are of the same diameter so as to eliminate the necessity for a floating seal.

By having the packing elements of the same diameter the fluid chambers defined by said elements will be such that when the parts of the tool are telescoped, or extended, one of the fluid chambers will increase in size to the same extent that the other chamber decreases in size. Hence fluid in said chambers will simply be transferred from one chamber to the other without developing undesired pressures therein which would interfere with the operation of the tool, or might even damage said tool.

Should one of the packing elements be of a difierent size as compared with the other, such undesired pressures would develop unless otherwise compensated for. For example, when the parts of the tool are moved relative to each and fluid is forced from the larger chamber into the smaller chamber the packing element of the latter would have to move or float so as to increase the size of the smaller chamber suflicieutly to accommodate the excess liquid. Such movement, or floating, of the packing element is undesirable and it would cause excessive wear and hence by having the packing elements of the same size such difliculty is overcome.

A further object of the invention is to provide a device of this character having improved stabilizing means.

A still further object of the invention is to provide a device or apparatus of this character having maximum operating efficiency.

Another object of the invention is to provide a device or apparatus of this character which requires a minimum of maintenance so that maintenance costs are relatively low.

Still another object of the invention is to provide a "ice device or apparatus of this character that is relatively inexpensive to manufacture.

The characteristics and advantages of the invention are further sufficiently referred to in connection with the following detailed description of the accompanying drawings which represent one embodiment. After considering these examples, skilled persons will understand that variations may be made without departing from the principles disclosed, and we contemplate the employment of any structures, arrangements or modes of operation that are properly within the scope of the ap pended claims.

Referring to the drawings: I

Fig. 1A is a side elevation, with a portion broken away of one end of a bumper sub embodying the present invention;

Fig. 1B is a side elevation, with a portion broken away, of the other end of same; and

Fig. 2 is a reduced sectional view taken on line 2-2 of Fig. 1B.

Referring more particularly to Figs. 1A and 1B the device comprises a barrel, indicated generally at 10, having the usual tapering internally threaded socket 11 at the upper end and below which is a thickened portion 12 through which an axial bore 14 of reduced diameter extends downwardly. Below the thickened portion 12 the barrel is interiorly enlarged to provide a cylindrical or chambered portion 15 which extends to the lower end of said barrel. The interior of the cylinder 15 has a portion 16 at the lower end that flares slightly outwardly and is internally threaded for threadable reception of the upper, slightly tapering externally threaded end portion 17 of a spline or drive sleeve 18 which is longitudinally grooved or splined interiorly at 20, as best shown in Fig. 2.

The mechanism includes a mandrel, indicated generally at 25, which comprises a part 26 having substantially the same external diameter as the external diameter of the barrel. There is the usual longitudinally extending tapered and externally threaded pin 27 for connection with the next part of the string. Successively upwardly of the part 26 of the mandrel, said mandrel comprises a reduced diameter portion 28, a second further reduced diameter portion 29, a longitudinally splined portion 30, and externally threaded further reduced diameter portion 31, and a still further slightly reduced diameter end portion 32. The mandrel has an internal, longitudinally extending bore of substantially the same diameter as the bore 14 of the barrel. Parts 28 to 32 inclusive of the mandrel are slidably receivable within the barrel, it being noted that the splined sleeve 18 includes a depending cylindrical portion 34 that has an internal diameter somewhat greater than the external diameter of the part 28 of the mandrel so that said part 28 will slide within said portion 34. The length of the portion 34 is such that when the mandrel is fully telescoped within the barrel, the upper end of the mandrel is spaced somewhat downwardly of the part 12 of the barrel and the lower free end of the portion 34 of the splined sleeve engages a shoulder 35 at the junction of the portion 26 and the portion 28 of said mandrel, said shoulder 35 comprising a striking shoulder for downtween said ribs 37, said fingers retaining the ring 38 against rotative movement on the mandrel. An annular lock out 44 is screwed onto the threaded portion 31 of the mandrel and retaim the lock ring against upward movement. Lock nut 44 is provided with an external recess 45 which is open at the upper end, closed at the lower end and in which received a stabilizer sleeve 46 of fibrous material such as, for example, Spauldite," said stabilizer extending upwardly of the upper end of the lock nut. Above the stabilizer is a packing element or sleeve 47 or rubber or other suitable material resistant to oil and other substances to which it may be subjected. The packing has grooves 48 in the upper and lower ends, said grooves being V-shaped in cross section and having disposed therein rings 49 or brass or other suitable material which are triangular in cross section and hold the inner and outer lips 47a of the element 47 from being deformed or forced inwardly of the V-shaped grooves A packing nut 50 having an external recess open at the bottom and closed at the top is screwed down onto the lock nut and the upper portion of the stabilizer and the packing element are received within the recess of said packing nut which is held against rotative movement by a set screw 51 in a radially extending tapped bore provided therefor, the inner end of said set screw being received in a recess 52 provided therefor in the mandrel portion 32. As will be readily apparent, the recesses of the lock nut and packing nut together form an annular groove in which the stabilizer and packing element are disposed and held against longitudinal movement. The packing element 47 seals off the upper portion of the mechanism.

Means for sealing the lower portion of the mechanism includes a packing element or sleeve 60 disposed at the lower end of the portion 29 of the mandrel. This packing element also is provided with grooves 61 in the upper and lower ends, said grooves being V-shaped. in cross section and receiving rings 62 which are triangular in shape in cross section. The lower ring 62 of the packing element 60 rests on the adjacent horizontal upper end of an annular quarter round ring 64 which has its inner surface curved to conform to the curvature at the lower end of the portion 29 of the mandrel. Above the packing element is a stabilizer sleeve 66 of suitable fibre material similar to that of the stabilizer 46 and above the stabilizer 66 is a stabilizer ring 67 secured to the portion 29 of the mandrel by set screws 68 threadably received in tapped openings provided therefor in the ring 67 and having the inner ends thereof received in recesses 69 provided therefor in the portion 29 of the mandrel.

The splined sleeve 18 is internally grooved longitudinally at 20 to provide longitudinally extending ridges 71, slidably received within the grooves 40 of the mandrel, the ribs 37 of the mandrel being slidably received in the grooves 20 of said splined sleeve. It is to be noted that the splined portion of the splined sleeve 18 is comparatively short with respect to the splined portion of the mandrel, so that the barrel unit and the mandrel have substantial relative longitudinal movement.

As pointed out above, the shoulder 35 provides a striking shoulder for downward jarring action. The lock ring is adapted to be struck by the longitudinally extending upwardly projecting annular portion 75 provided therefor on the upper end of the splined sleeve. Both ends of the operating parts of the mechanism are sealed off by the

packing elements

47 and 60 and are held in alignment by the

stabilizers

46 and 66 to prevent the parts from wobbling relative to each other. Moreover, the stabilizers will take such wear that may occur and as they may be easily replaced and are relatively inexpensive, replacement of costly parts is eliminated. The stroke of the mechanism is such that when the parts are extended relative to each other, the free end of the cylindrical portion 34 of the splined sleeve still covers the packing element 60. The space between the splined portion of the mandrel and the adjacent portion of the barrel unit is provided with oil of any suitable well known 4 character and filling is efifected through tapped filling openings 66a provided therefor, said filling openings being closed by externally threaded fill plugs 66b. It will be apparent that the packing elements are of the same diameter so that floating seals are eliminated.

-It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it is thought that it will be apparent that the various changes may be made in the form, construction and arrangement of the parts of the invention and the method of operation thereof without departing from the spirit and scope thereof or sacrificing all of its material advantages, the embodiment herein before described being merely for purposes of illustration.

We claim:

1. An oil sealed bumper sub for connection in string of pipe, comprising: a tubular mandrel having a body portion with means at one end for. connection to an adjacent part of the pipe string, first, second, third and fourth successively reduced diameter portions extending from the opposite end of said body, a shoulder at the outer end of the first reduced diameter portion, a rounded shoulder at the opposite end thereof connecting same with the second reduced diameter portion, the first and second reduced diameter portions being exteriorly cylindrical, the third reduced diameter portion being splined and having longitudinally extending grooves with longitudinally extending ribs therebetween, and the fourth reduced diameter portion being exteriorly threaded; a lock ring at the inner ends of the spline ribs, said lock ring having its inner end abutting the adjacent end of said ribs and having relatively short, longitudinally extending fingers disposed in the adjacent ends of said grooves between said ribs; a lock nut threaded onto the threaded fourth reduced diameter portion of the mandrel securing said lock ring against upward longitudinal movement, said lock nut having an annular external groove open at the upper end and closed at the lower end; a stabilizer sleeve disposed in said annular groove and extending upwardly of the upper end of said lock nut; an annular packing element disposed at the upper end of said stabilizer; a packing nut threadably received on said threaded fourth reduced diameter portion of the mandrel and shutting the adjacent end of the lock nut, the packing nut having an annular external recess open at the bottom and closed at the top, the upper portion of the stabilizer and said packing being received in said recess; releasable means for securing the packing nut against rotation on the mandrel; a barrel unit comprising a barrel having a cylindrical portion in which the mandrel is slidably receivable and having means at its outer end for connection with an adjacent part of a pipe string, the lower free end of said barrel having an internal portion flaring slightly outwardly and threaded; a spline sleeve having an externally threaded portion threadably connected with the threaded portion of said barrel, the upper end of said spline sleeve having an annular striking part enagageable with the lock ring for effecting upward jarring action.

' said spline sleeve having a short splined portion cooperatively connected with the splined portion of the mandrel, a cyclindrical downward extension on said spline sleeve having an enlarged internal diameter so that the first reduced diameter portion of the mandrel slides therein and the lower free end of said extension is adapted to engage said striking shoulder to efiect downward jarring action; a ring on the rounded shoulder between the first and second reduced diameter portions, said ring being quarter round in cross section; an annular packing element on the second reduced diameter portion, said packing element resting on said ring; a stabilizer sleeve on said second reduced diameter portion above said packing; a stabilizer ring on said second reduced diameter portion above said stabilizer; set screw means securing said stabilizer ring to said second reduced diameter portio and Oil in the space between the mandrel and said barrel unit in the region between the upper end of the second reduced diameter portion and the lock ring.

2. An oil sealed bumper sub for connection in string of pipe, comprising: a tubular mandrel having a body portion with first, second, third and fourth successively reduced diameter portions at end of said body, a shoulder at the outer end of the first reduced diameter portion, a rounded shoulder at the opposite end thereof, connecting same with the second reduced diameter portion. the first and second reduced diameter portions being exteriorly cylindrical, the third reduced diameter portion being splined and having longitudinally extending grooves with longitudinally extending ribs therebetween, and the fourth reduced diameter portion being exteriorly threaded; a lock ring at the inner ends of the spline ribs and having relativelyshort, longitudinally extending fingers disposed in the adjacent ends of said grooves between said ribs; a lock nut threaded onto the threaded fourth reduced diameter portion of the mandrel securing said lock ring against upward longitudinal movement, said lock nut having an annular external groove open at the upper end and closed at the lower end; a stabilizer sleeve disposed in said annular groove and extending upwardly of the upper end of said lock nut; an annular packing element disposed at the upper end of said stabilizer; a packing nut threadably received on said threaded fourth reduced diameter portion of the mandrel, the packing nut having an annular external recess open at the bottom and closed at the top, the upper portion of the stabilizer and said packing being received in said recess; releasable means for securing the packing nut against rotation on the mandrel; a barrel unit comprising a barrel having a cylindrical portion in which the mandrel is slidably receivable; a spline sleeve connected to the lower end of said barrel, the upper end of said spline sleeve having an annular striking part engageable with the lock ring for effecting upward jarring action, said splined sleeve having a short splined portion cooperatively connected with the splined portion of the mandrel, a cylindrical downward extension on said splined sleeve having an enlarged internal diameter so that the first reduced diameter portion of the mandrel slides therein and the lower free end of said extension is adapted to engage the striking shoulder between the body and said first reduced diameter portion to effect downward jarring action; a ring on the rounded shoulder between the first and second reduced diameter portions; an annular packing element on the second reduced diameter portion and resting on said ring; a stabilizer sleeve on said second reduced diameter portion above said packing; a stabilizer ring on said second re duced diameter portion above said stabilizer; means securing said stabilizer ring to said second reduced diameter portion; and oil in the operating portion of the device and sealed in by said packing elements.

References Cited in the file of this patent UNITED STATES PATENTS 797,152 Sheckler Aug. 15, 1905 1,542,319 Pyles June 16, 1925 1,714,803 Mueller May 28, 1929 2,180,223 Collett Nov. 14, 1939 2,210,826 Williams Aug. 6, 1940 2,309,872 Shaffer et a1 Feb. 2, 1943 2,462,257 Cunningham Feb. 22, 1949 2,463,353 Brown et a1. 'Mar. 1, 1949 2,521,127 Price Sept. 5, 1950 2,568,256 Shafler Sept. 18, 1951 2,575,394 Rice Nov. 20, 1951 2,641,514 Hecker June 9, 1953 2,721,056 Storm Oct. 18, 1955 2,818,232 Osmun Dec. 31, 1957 FOREIGN PATENTS 19,469 Great Britain Sept. 27, 1899