Collar unthreader

Claim 2

Apparatus for unthreading casing, tubing and drill collars or the like, said apparatus comprising: a high torque lathe having a chuck; a chuck adaptor for a collar having a cylindrical shaft fixed in said chuck, said adaptor including a hollow housing closed at one of its ends, open at its other end, and having a cylindrical surface, the external surface of said housing closed end being fixed relative to said shaft in a position concentric therewith, said housing having an arcuate slot through the cylindrical wall thereof spaced from each end thereof; a first ring fixed relative to said housing inside thereof between said slot and said housing closed end; a second ring fixed relative to said housing inside thereof between said slot and said housing open end; and a third ring rotatable against said housing internal surface in the vicinity of said slot, said third ring having lever means fixed thereto and projecting radially through and outwardly of said slot; said first and second rings having concentric internal cylindrical surfaces of substantially the same diameter, said first and second ring internal surfaces being eccentric to said housing internal surface, said third ring having a cylindrical internal surface eccentric to said housing internal surface and rotatable by said lever means to and from a position in alignment with the internal surfaces of said first and second rings.

Claim 3

The invention as defined in claim 1, wherein: said housing closed end has a substantially flat internal surface, each of said rings having substantially flat and parallel sides normal to the respective internal surfaces thereof, one of said first ring sides being in engagement with said housing closed end internal surface said third ring sides lying in slidable engagement with respective sides of said first and second rings, said first and second rings having cylindrical external surfaces in engagement with said housing internal cylindrical surface, said third ring having a cylindrical external surface rotatable in engagement with said housing internal surface, said third ring having axial keyways in said cylindrical internal surface thereof; and gripping dies in the shape of keys in said keyways.

Claim 4

The invention as defined in claim 2, wherein: said lever means includes a projection threaded into said third ring, said screw means being threaded through the wall of said housing into engagement with said first and second rings; the external edge of said second ring internal surface being beveled, said lathe having a framing; and a wrench for attachment to a pipe and engageable with said framing to prevent rotation of said pipe.

Claim 5

Apparatus for unthreading drill collars or the like, said apparatus comprising: a chuck adaptor having a shaft, said adaptor including a hollow housing closed at one of its ends, open at its other end, and having a cylindrical internal surface, said housing closed end being fixed relative to said shaft, said housing having an arcuate slot through the wall thereof spaced from each end thereof; a first ring fixed relative to said housing inside thereof between said slot and said housing closed end; a second ring fixed relative to said housing inside thereof between said slot and said housing open end; and a third ring rotatable against said housing internal surface in the vicinity of said slot, said third ring having lever means fixed thereto and projecting radially through and outwardly of said slot, said first and third rings having concentric internal cylindrical surfaces of substantially the same diameter; said first and third ring internal surfaces being eccentric to said housing internal surface, said third ring having a cylindrical internal surface eccentric to said housing internal surface and rotatable by said lever means to and from a position in alignment with the internal surfaces of said first and second rings, said third ring having an external cylindrical surface rotatable in engagement with said housing internal surface, said chuck adaptor being capable of holding a cylindrical body when the same is placed inside said first, second and third rings, and said third ring is turned via said lever means.

Claim 6

Apparatus for unthreading drill collars or the like, said apparatus comprising: a chuck adaptor having a shaft, said adaptor including a hollow housing closed at one of its ends, open at its other end, and having a cylindrical internal surface, said housing closed end being fixed relative to said shaft, said housing having an arcuate slot through the wall thereof spaced from each end thereof; a first ring fixed relative to said housing inside thereof between said slot and said housing closed end; a second ring fixed relative to said housing inside thereof between said slot and said housing open end; and a third ring rotatable against said housing internal surface in the vicinity of said slot, said third ring having lever means fixed thereto and projecting radially through and outwardly of said slot, said first and third rings having concentric internal cylindrical surfaces of substantially the same diameter; said first and third ring internal surfaces being eccentric to said housing internal surface, said third ring having a cylindrical internal surface eccentric to said housing internal surface and rotatable by said lever means to and from a position in alignment with the internal surfaces of said first and second rings, said third ring having an external cylindrical surface rotatable in engagement with said housing internal surface, said chuck adaptor being capable of holding a cylindrical body when the same is placed inside said first, second and third rings, and said third ring is turned via said lever means.

Claim 7

The invention as defined in claim 4, wherein: gripping dies are fixed relative to said third ring inside said internal surface thereof.

Claim 8

The invention as defined in claim 5, wherein: said gripping dies are positioned around said third ring opposite the side on which the narrowest radial dimension thereof is positioned.

Claim 9

The invention as defined in claim 6, wherein: keyways are disposed in said third ring internal surface, and said gripping dies are wedged in said keyways.

Claim 10

The invention as defined in claim 4, wherein: said housing has a cylindrical internal surface of revolution about a first axis, said third ring having a cylindrical internal surface of revolution about a second axis spaced from said first axis in a direction therefrom opposite the side on which said lever means is located.