US2690783A - Locking device for casing rollers - Google Patents

Description

1954 A. J. COLMERAUER LOCKING DEVICE FOR CASING ROLLERS 2 Sheets-Sheet 1 Filed June 23 1951 INVENTOR. ANDREW 4/. CULMERAUER ATTORNEY Oct. 1954 A. J. COLMERAUER 2,690,783

LOCKING DEVICE FOR CASING ROLLERS Filed June 25, 1951 2 Sheets-Sheet 2 INVENTOR. ANDREW .1. COLMERAUER ATTORNEY Patented Oct. 5, 1954 LOCKING DEVICE FOR CASING ROLLERS Andrew J. Colmerauer, Redondo Beach, Calif., assignor of one-half to Leo T. Langer, Long Beach, Calif.

Application June 23, 1951, Serial No. 233,219

1 Claim.

This invention relates to improvements in casing rollers of the type shown in U. S. Patent No. 2,011,036 issued to me on August 13, 1935.

Casing rollers are employed to roll or swedge collapsed oil well casing back to its normal, cylindrical shape. Casing rollers are usually mounted on the lower end of a string of drill pipe. The drill pipe and casing roller are lowered into the well to the point where the casing has collapsed and are rotated while continuing to lower and rotate the drill pipe, thereby forcing the well casing back toits normal shape.

The casing roller shown in my former patent has proven to be very satisfactory in use but because of the very high pressures developed during the rolling operation (due to the weight of the drill pipe and the horse power employed to rotate the pipe) considerable wear takes place within the body of the casing roller. With the device shown in my prior patent the radial wear between the body of the tool and the roller sleeves may be compensated for by replaceable wear sleeves. Considerable wear also takes place axially between the upper shoulder of the retaining cone and the lower shoulder of the adjacent eccentric or offset portion. A small amount of such wear permits the weight of the drill pipe to be exerted against the retainer balls, thereby crushing them.

It is the object of the present invention to provide means for permitting a substantial amount of axial Wear to take place before any load will be placed on the retainer balls.

In the drawings, illustrating my improved design,

Figure 1 is an elevation, partly in section, of a casing roller embodying my improved locking device.

Figure 2 is an enlarged section of the locking device shown in Figure 1.

Figure 3 is a cross sectional elevation of Figure 2, with the locking balls omitted.

Figure 4 illustrates another embodiment of my invention.

Figure 5 illustrates still another embodiment of my invention.

Referring to the drawings, Figure 1 shows a section of a well casing I having a partially collapsed portion 2. The lower end of a string of drill pipe is indicated at 3. My casing roller A is shown attached to the lower end of the drill pipe by means of a conventional threaded box 4 and pin 5. Integral with and extending downwardly from the box 4 is a cylindrical bearing surface 6 concentric with the vertical axis of the tool. Below the bearing surface 6 is a second cylindrical bearing surface 1 which i oifset eccentrically to the vertical axis of the tool. Below the bearing surface 1 is a cylindrical extension 8 which is concentric with the vertical axis of the tool. The diameter of the extension 8 is less than that of the bearing surface member '1, resulting in an annular, downwardly facing shoulder [8 on the lower end of member 1. Rotatably mounted on each of the bearing surfaces 6 and l are cylindrical roller sleeves 9 and I0. Each roller sleeve has a concentric bore which makes a loose fit on the corresponding bearing surface.

The outside diameters of the roller sleeves, together with their respective offsets, are such that the over-all diameter of the casing roller is approximately the same as the inside diameter of the casing which is to be expanded.

The roller sleeves are retained in place by a conical nose piece ll rotatably mounted on the lower end of the extension 8.

The present invention relates to the manner in which the nose piece H is mounted on the extension 8.

The lower portion of the extension 8 is of reduced diameter as indicated at l2 forming a downwardly facing shoulder 13. The bore of the conical nose piece H is reduced as indicated at M, forming an upwardly facing shoulder which bears against the downwardly facing shoulder l3.

Locking means to prevent the conical nose piece II from becoming detached from the extension 8 is provided by a row of steel balls [5 confined in mating grooves l6 and I! formed in the extension 8 and the nose piece I I, respectively. The grooves l6 and H are offset slightly (about inch to inch or more) from each other in an axial direction so that the balls l5 are confined between one shoulder of the groove l6 and the opposite shoulder of the groove 11. In the drawings, the balls l5 are shown confined between the upper shoulder of groove I! and the lower shoulder of groove IS.

The foregoing locking arrangement permits cumulative wear of approximately inch to inch, or more, to take place on the shoulders 13 and I8 before the weight of the drill pipe can be exerted against the balls 15. The balls 15 are solely for locking the nose piece H to the extension 8. They are not load-carrying bearings. Any appreciable load on the bearings wouldv crush them. If the mating grooves I6 and Il were not offset, and if the balls l5 made a snug fit in the mating grooves, the slightest wear on shoulders l3 and i8 would permit the weight of the drill pipe 3 to be transmitted to the balls I5, thereby crushing them. If the balls I5 were not a sung fit between the shoulders I8 and I! the nose piece I I would be able to move up and down on the extension 8, thus permitting the roller sleeves to move up and down and become jammed on one another.

Figure 4 illustrates a slightly different embodiment of my invention wherein there is no lower shoulder on the bearing race. This arrangement permits a greater amount of wear to take place on the shoulders I3 and I8 than is possible with the groove shown in Figs. 1, 2 and 3 before the balls can be subjected to any weight.

Figure 5 illustrates still another embodiment of my invention in which there is no upper shoulder on the groove [61) and no lower shoulder on the groove I'Ib. This arrangement also provides for greater Wear on the shoulders I3 and I8 before the balls I 5 can be subjected to any weight.

I claim:

In a casing roller comprising a body having a plurality of superposed roller sleeves eccentrically and rotatably mounted thereon, retaining means for said roller sleeves comprising a conical nose piece having an axial bore therethrough, a groove circumferentially disposed in the inner face of said bore and forming a downwardly facing bearing shoulder adapted to bear against a row of retaining balls, retaining balls in said groove, said groove being of substantially greater width, in

an axial direction, than the diameter of said balls, the lower portion of said bore being of reduce diameter to form an upwardly facing annular bearing shoulder, an opening through the wall of said nose piece for inserting retaining balls, means for removably closing said opening, a downwardly disposed cylindrical extension on the lower end of said casing roller body adapted to fit rotatably within the bore of said nose piece. a circumferentially disposed groove in the outer face of said extension and offset in an axial direction from the groove in said nose piece thereby forming an upwardly facing shoulder bearing against said retaining balls, said latter groove also being of substantially greater width, in an axial direction, than the diameter of said retainer balls, the lower portion of said extension being of reduced diameter forming a downwardly facing bearing shoulder in said nose piece whereby said retaining balls lock said nose piece rotatably on said extension while simultaneously contacting said shoulders in said grooves and hold the bearing surfaces on said nose piece and extension in contact in load-carrying relation.

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