Radial cutting tool for cutting thick-walled tubular members
AssigneeWellcutter Inc.
InventorJerry H. Robinson
Life of this patent
Estimating the term…
Abstract
A portable cutting tool has an annular frame for surrounding the pipe. A rotatable ring on the frame carries a radially fed cutter which includes a bit subassembly for cutting the tubular member. The bit subassembly is indexed in response to orbital movement of the cutter. The bit subassembly includes a bit planar support block which has a dimension (as measured parallel to the longitudinal axis of the tubular member being cut) which is less than that of the bit which it carries. In such a manner, a channel passageway may be formed between the bit support block and the tubular member being cut as the bit penetrates into the tubular member during the cutting operation such that lubricating/flushing fluid may be directed to the bit.
Claims25
A cutting tool for cutting tubular members comprising:
- an annular frame assembly which is concentrically positionable about the tubular member to be cut such that said cutting tool is disposed in a cutting plane which is normal to the tubular member's longitudinal axis;
- and
- a radial cutting assembly coupled to said annular frame assembly for orbital movement about said tubular member within said cutting plane so as to cut said tubular member, wherein
- said radial cutting assembly includes a bit subassembly having (i) a bit support block which has opposed planar surfaces parallel to said cutting plane so as to establish therebetween a thickness dimension of said bit support block, and (ii) a bit carried rigidly at a forward end of said bit support block so as to be in a mounting plane which is substantially transverse to said opposed parallel planar surfaces and thereby oriented substantially parallel to the tubular member's longitudinal axis, and wherein
- said bit has a substantially triangular cutting edge having lateral portions which extend past said opposed parallel planar surfaces of said bit support block such that said bit cuts a channel in the tubular member having a dimension measured parallel to the tubular member's longitudinal axis which is greater than the thickness dimension of said bit support block.
A cutting tool for cutting a tubular member comprising:
- an annular frame having a rotatable ring which is adapted to surround the tubular member to be cut;
- a radial cutting assembly radially connected to said rotatable ring so as to be orbitally movable about the tubular member to be cut in response to rotation of said rotatable ring;
- a bit subassembly carried by said radial cutting assembly for cutting said tubular member;
- and
- a drive/indexing assembly for (1) drivenly rotating said rotatable ring to cause said radial cutting assembly to move orbitally about said tubular member, and (2) indexing said bit radially toward a central longitudinal axis of said tubular member in response to said orbital movement of said radial cutting assembly whereby said tubular member is cut thereby, wherein
- said bit subassembly includes (i) a cutting bit having a dimension D.sub.1 as measured parallel to said central longitudinal axis, and (ii) a planar bit support block which is disposed in a cutting plane transverse to said central longitudinal axis and which radially extends rearwardly of said bit and having a dimension D.sub.2 as measured parallel to said central longitudinal axis which is less than said dimension D.sub.1 of said bit, whereby a channel passageway coincident to said cutting plane is formed by said bit support block as said bit penetrates into said tubular member, and wherein said drive/indexing assembly includes:
- an indexing gear intermeshed with said stationary gear of said annular frame;
- an indexing block rigidly coupled to said bit support block;
- and
- a drive train operatively connecting said indexing gear and indexing block for translating rotational movement of said indexing gear into rectilinear movement of said indexing block in response to said orbital movement of said radial cutting assembly,
- said drive train including
- an input shaft;
- a drive gear assembly operatively connecting said indexing gear and input shaft so that said input shaft rotates in response to rotation of said indexing gear;
- a rotatable threaded indexing shaft which is threadably coupled to indexing block;
- and
- a gear reduction assembly operatively interconnecting said input and indexing shafts so that said indexing shaft rotates in response to said input shaft and thereby rectilinearly moves said indexing block.
Dependencies are inferred from the claim text.