초록 ▼

A downhole tool comprises a body having slots communicating the outside of the body with the body through-bore. A sleeve actuator and mandrel are selectively axially slidable. The actuator has flanges extending into the slots. The flanges have ribs on their sides that are inclined at an acute angle

A downhole tool comprises a body having slots communicating the outside of the body with the body through-bore. A sleeve actuator and mandrel are selectively axially slidable. The actuator has flanges extending into the slots. The flanges have ribs on their sides that are inclined at an acute angle to the longitudinal axis of the tool. Hollow bars are slidable in the slots and they have channels inside corresponding with, and engaged in, the ribs of the flanges. The sleeve actuator slides in the body between a tool actuated position and a tool deactuated position. The mandrel is selectively axially slidable between a tool actuated position, an interlock position and a sleeve-lock position. A lock ball locks the sleeve actuator with respect to the body in the tool deactuated position and while the mandrel is between the interlock and sleeve-lock positions. The lock ball also locks the sleeve actuator with respect to the mandrel while the mandrel is between said interlock and tool actuated positions.

대표청구항 ▼

What is claimed is: 1. A downhole tool comprising: a) a body having a longitudinal axis and a body through-bore, a slot communicating the outside of the body with the body through-bore; b) a sleeve actuator mandrel having a sleeve actuator mandrel through-bore and being selectively axially slidable

What is claimed is: 1. A downhole tool comprising: a) a body having a longitudinal axis and a body through-bore, a slot communicating the outside of the body with the body through-bore; b) a sleeve actuator mandrel having a sleeve actuator mandrel through-bore and being selectively axially slidable in the body through-bore; c) a flange on the sleeve actuator mandrel extending into said slot and having one of ribs and channels formed on its sides and inclined at an acute angle to the longitudinal axis; d) a hollow bar slidable with a radial component in the slot, the other of channels and ribs being formed on the bar and corresponding with, and engaged in, said one of said ribs and channels of the flange, and e) seals between said sleeve actuator mandrel and body beyond both ends of said slot, and a seal around the bar in the slot, which seals define between them a chamber enclosing lubricating oil. 2. A downhole tool according to claim 1, wherein said sleeve actuator mandrel has a port therethrough which aligns with a jet in the body when the sleeve actuator mandrel is in its tool actuated position, whereupon the through-bore of the sleeve actuator is in fluid communication with said jet whereby drilling fluid under pressure in said mandrel through-bore is directed onto the well bore in the region of said bars. 3. A downhole tool according to claim 1, wherein the axis of the slot is radial with respect to said longitudinal axis. 4. A downhole tool according to claim 1, wherein said flange is separate from the sleeve actuator mandrel but is locked thereon by circumferential dovetailed slots formed on a sector of the sleeve actuator mandrel adjacent an open sector thereof, and corresponding dovetails on the base of said flange engaged with said dovetailed slots of the sleeve actuator mandrel. 5. A downhole tool according to claim 4, wherein the tool is assembled by inserting said flange engaged with said bar in said slot so that said dovetails bear against said open sectors of the sleeve actuator mandrel, and by rotating said mandrel so that said dovetail slots engage said dovetails, means being provided to prevent the sleeve actuator mandrel from rotating in the body during use. 6. A downhole tool according to claim 5, wherein said rotation prevention means comprises a pin in the body extending into a slot in the sleeve actuator mandrel. 7. A downhole tool according to claim 1, wherein there are a plurality of said bars, slots and flanges spaced around the longitudinal axis of the tool. 8. A downhole tool according to claim 7, wherein there are three of said bars, slots and flanges. 9. A downhole tool according to claim 7, wherein said tool is an under-reamer and said bars are provided with cutting elements to effect under-reaming when the tool is actuated in a well bore having a pilot hole receiving the tool. 10. A downhole tool according to claim 9, wherein said body is thickened in the region of said slots and bars to support said bars. 11. A downhole tool according to claim 9, wherein said body has fins ahead of said slots having dimensions to match said pilot hole and bear against its surface and stabilise the tool, in use, said fins being provided with a hardened wear surface to minimise wear. 12. A downhole tool according to claim 7, wherein the tool is an adjustable stabiliser, said bars being provided with hardened wear surfaces to minimise wear of the bars, in use. 13. A downhole tool according to claim 1, wherein the tool is an azimuth controller, wherein one or more bars in one or more slots are arranged asymmetrically around the longitudinal axis of the tool. 14. A downhole tool according to claim 13, further comprising one or more static blades. 15. A downhole tool comprising: a) a body having a longitudinal axis and a body through-bore, the body mounting an actuatable tool; b) a sleeve actuator having an actuator through-bore and being axially slidable in the body through-bore between a tool actuated position and a tool deactuated position; c) a mandrel having a mandrel through-bore and being selectively axially slidable in the body through-bore between a tool actuated position, an interlock position and a sleeve-lock position; wherein: d) an extension of the mandrel is a close sliding fit inside a first end of the sleeve actuator; e) said first end captivates a lock element; f) said body has an internal groove positioned so that when said sleeve actuator is in said tool deactuated position, said lock element is aligned with said groove and held in engagement therein by said extension while the mandrel is between its interlock and sleeve-lock positions; and g) said mandrel has an external recess positioned so that, when said mandrel is in said interlock position, said lock element is aligned with said recess, whereupon movement of the mandrel towards said tool actuated position releases said lock element from said groove permitting said sleeve actuator to be moved by the mandrel to said tool actuated position, said mandrel and sleeve actuator being locked together by the body holding said lock element in said recess between said interlock and tool actuated positions of the mandrel. 16. A downhole tool according to claim 15, wherein said lock element is a ball. 17. A downhole tool according to claim 15, wherein said sleeve actuator has ports therethrough which align with jets in the body when the sleeve actuator is in its tool actuated position, whereupon the through-bore of the sleeve actuator is in fluid communication with said jets, and whereby drilling fluid under pressure in said body through-bore is directed into the well bore. 18. A downhole tool according to claim 17, further comprising a valve operated by the sleeve actuator to restrict drilling fluid flow through the tool past said jets. 19. A downhole tool comprising: a) a body having a longitudinal axis and a body through-bore, the body mounting an actuatable tool; b) a sleeve actuator having an actuator through-bore and being axially slidable in the body through-bore between a tool actuated position and a tool deactuated position; c) a mandrel having a mandrel through-bore and being selectively axially slidable in the body through-bore between a tool actuated position, an interlock position and a sleeve-lock position; wherein: d) first lock means to lock the sleeve actuator with respect to the body in said tool deactuated position and while said mandrel is between said interlock and sleeve-lock positions; and e) second lock means to lock the sleeve actuator with respect to the mandrel and while said mandrel is between said interlock and tool actuated positions. 20. A downhole tool according to claim 19, wherein said first and second means comprise a lock element captivated by the sleeve actuator and located in one of a groove in the body or a recess on the mandrel. 21. A downhole tool according to claim 20, wherein alignment of said groove and recess occurs in said interlock position of the mandrel, which coincides with said tool deactuated position of the sleeve actuator. 22. A downhole tool according to claim 20 wherein said lock element is a ball. 23. A downhole tool comprising: a) a body mounting an actuatable tool and having a longitudinal axis and a body through-bore, a slot communicating the outside of the body with the body through-bore; b) a sleeve actuator having an actuator through-bore and being axially slidable in the body through-bore between a tool actuated position and a tool deactuated position; c) a mandrel having a mandrel through-bore and being selectively axially slidable in the body through-bore between a tool actuated position, an interlock position and a sleeve-lock position; wherein: d) first lock means to lock the sleeve actuator with respect to the body in said tool deactuated position and while said mandrel is between said interlock and sleeve-lock positions; e) second lock means to lock the sleeve actuator with respect to the mandrel and while said mandrel is between said interlock and tool actuated positions; f) a flange on the sleeve actuator extending into said slot and having one of ribs and channels formed on its sides and inclined at an acute angle to the longitudinal axis; and g) a hollow bar slidable with a radial component in the slots, the other of channels and ribs being formed on the bar and corresponding with, and engaged in, said one of said ribs and channels of the flange. 24. A downhole tool according to claim 23, wherein said first and second lock means comprise a lock element captivated by the sleeve actuator and located in one of a groove in the body or a recess on the mandrel. 25. A downhole tool according to claim 24, wherein said lock element is a ball. 26. A downhole tool according to claim 23, wherein seals between said sleeve actuator and body beyond both ends of said slot define, between them and a seal around the bar in the slot, a chamber enclosing lubricating oil. 27. A downhole tool according to claim 23, wherein said sleeve actuator has a port therethrough which aligns with a jet in the body when the sleeve actuator mandrel is in its tool actuated position, whereupon the through-bore of the sleeve actuator is in fluid communication with said jet whereby drilling fluid under pressure in said mandrel through-bore is directed onto the well bore in the region of said bars. 28. A downhole tool according to claim 23, wherein the axis of the slot is radial with respect to said longitudinal axis. 29. A downhole tool according to claim 23, wherein said flange is separate from the sleeve actuator but is locked thereon by circumferential dovetailed slots formed on a sector of the sleeve actuator adjacent an open sector thereof, and corresponding dovetails on the base of said flange engaged with said dovetailed slots of the sleeve actuator. 30. A downhole tool according to claim 29, wherein the tool is assembled by inserting said flange engaged with said bar in said slot so that said dovetails bear against said open sectors of the sleeve actuator, and by rotating said actuator so that said dovetail slots engage said dovetails, means being provided to prevent the sleeve actuator from rotating in the body during use. 31. A downhole tool according to claim 30, wherein said rotation prevention means comprises a pin in the body extending into a slot in the sleeve actuator or mandrel. 32. A downhole tool according to claim 23, wherein there are a plurality of said bars, slots and flanges spaced around the longitudinal axis of the tool. 33. A downhole tool according to claim 32, wherein there are three of said bars, slots and flanges. 34. A downhole tool according to claim 33, wherein the tool is an adjustable stabiliser, said bars being provided with hardened wear surfaces to minimise wear of the bars, in use. 35. A downhole tool according to claim 34, further comprising one or more static blades. 36. A downhole tool according to claim 32, wherein said tool is an under-reamer and said bars are provided with cutting elements to effect under-reaming when the tool is actuated in a well bore having a pilot hole receiving the tool. 37. A downhole tool according to claim 36, wherein said body is thickened in the region of said slots and bars to support said bars. 38. A downhole tool according to claim 36, wherein said body has fins ahead of said slots having dimensions to match said pilot hole and bear against its surface and stabilise the tool, in use, said fins being provided with a hardened wear surface to minimise wear. 39. A downhole tool according to claim 23, wherein the tool is an azimuth controller, wherein one or more bars in one or more slots are arranged asymmetrically around the longitudinal axis of the tool. 40. A downhole tool comprising: a) a body having a longitudinal axis and a body through-bore, a slot communicating the outside of the body with the body through-bore; b) a sleeve actuator mandrel having a sleeve actuator mandrel through-bore and being selectively axially slidable in the body through-bore; c) a bar slidable with a radial component in the slot; d) a coupling between the sleeve actuator mandrel and the bar to slide the bar with a radial component in the slot on axial sliding of the sleeve actuator mandrel in the body through-bore; and e) seals between said sleeve actuator mandrel and body beyond both ends of said slot, and a seal around the bar in the slot, which seals define between them a chamber enclosing lubricating oil to lubricate said coupling.