Hydraulic jarring mechanism

Claim 2

A jarring mechanism comprising: a. first and second relatively movable operating means connected with each other; b. a fluid-containing reservoir included with said first and second operating means; c. compression means connected with said first and second operating means and said reservoir means for generating and maintaining a first substantially fixed pressure in a first portion of said fluid as said first and second operating means are moved relative to each other along a first portion of their relative travel, said first pressure resisting relative movement between said first and second operating means; and d. release means connected with said first and second operating means and said reservoir means for reducing said first pressure to a second, lower pressure when said first and second operating means are moved along a second portion of their relative travel to reduce the resistance to relative movement between said first and second operating means whereby a jarring blow is delivered between said first and second operating means; e. said compression means including control means for automatically regulating flow of said fluid from said first portion of said reservoir to a second portion of said reservoir for maintaining said first pressure at a substantially constant value; f. said control means comprising variable flow passage means for automatically varying flow path dimensions in a flow passage extending between said first and second reservoir portions and including adjustable means for adjustably varying the length of said flow passage means.

Claim 3

A jarring mechanism as defined in claim 1 wherein said adjustable means includes pressure responsive wall means forming a first portion of said flow passage means for varying the cross-sectional area of said flow passage means in response to pressure changes in said fluid.

Claim 4

A jarring mechanism as defined in claim 2 wherein said adjustable means includes mating components comprising an externally threaded substantially cylindrical body received within an internally threaded sleeve bore with the peaks of the threads formed on at least one of said mating components spaced from the valleys in the other of said mating components to form at least one helical flow path between said mating components, said body being rotatable within said sleeve bore for moving said body axially with respect to said bore to vary the length of said helical flow path.

Claim 5

A jarring mechanism as defined in claim 3 wherein said pressure responsive wall means includes a bore extending axially through a threaded portion of said cylindrical body to form a tubular wall segment whereby pressure changes in said fluid move said tubular segment radially to vary the spacing between said thread peaks and valleys in said mating components.

Claim 6

A jarring mechanism as defined in claim 4 wherein said cylindrical body is provided with helical threads having a cross section substantially in the form of a truncated triangle.

Claim 7

A jarring mechanism comprising: a. first and second relatively movable operating means connected with each other; b. a fluid-containing reservoir included with said first and second operating means; c. compression means connected with said first and second operating means and said reservoir means for generating and maintaining a first substantially fixed pressure in a first portion of said fluid as said first and second operating means are moved relative to each other along a first portion of their relative travel, said first pressure resisting relative movement between said first and second operating means; d. release means connected with said first and second operating means and said reservoir means for reducing said first pressure to a second, lower pressure when said first and second operating means are moved along a second portion of their relative travel to reduce the resistance to relative movement between said first and second operating means whereby a jarring blow is delivered between said first and second operating means; and e. control means for automatically regulating flow of said fluid from said first portion of said reservoir to a second portion of said reservoir for maintaining said first pressure at a substantially constant value, said control means including variable flow passage means for automatically varying flow path dimensions in a flow passage extending between said first and second reservoir portions; f. said variable flow passage means including: i. regulator sleeve means forming a second portion of said flow passage means; ii. axially spaced first and second sliding seal means carried by said regulator sleeve means and exposed to said fluid in said first and second reservoir portions for moving said regulator sleeve means axially in response to pressure differentials between said first and second reservoir portions; and iii. restriction forming means included with said regulator sleeve means for varying the dimensions of said flow passage means as said regulator sleeve means is moved axially.

Claim 8

A jarring mechanism comprising: a. first and second relatively movable operating means connected with each other; b. a fluid-containing reservoir included with said first and second operating means; c. compression means connected with said first and second operating means and said reservoir means for generating and maintaining a first substantially fixed pressure in a first portion of said fluid as said first and second operating means are moved relative to each other along a first portion of their relative travel, said first pressure resisting relative movement between said first and second operating means; d. release means connected with said first and second operating means and said reservoir means for reducing said first pressure to a second, lower pressure when said first and second operating means are moved along a second portion of their relative travel to reduce the resistance to relative movement between said first and second operating means whereby a jarring blow is delivered between said first and second operating means; and e. control means for automatically regulating flow of said fluid from said first portion of said reservoir to a second portion of said reservoir for maintaining said first pressure at a substantially constant value, said control means including variable flow passage means for automatically varying flow path dimensions in a flow passage extending between said first and second reservoir portions; f. said variable flow passage means including: i. regulator sleeve means forming a second portion of said flow passage means; ii. axially spaced first and second sliding seal means carried by said regulator sleeve means and exposed to said fluid in said first and second reservoir portions for moving said regulator sleeve means axially in response to pressure differentials between said first and second reservoir portions; and iii. restriction forming means included with said regulator sleeve means for varying the dimensions of said flow passage means as said regulator sleeve means is moved axially.

Claim 9

A jarring mechanism as defined in claim 6 wherein said regulator sleeve means includes adjustable means for adjustably varying the length of said flow passage means.

Claim 10

A jarring mechanism as defined in claim 7 wherein said adjustable means includes pressure responsive wall means forming a first portion of said flow passage means for varying the cross-sectional area of said flow passage means in response to pressure changes in said fluid.

Claim 11

A jarring mechanism as defined in claim 6 for imparting a jarring blow to objects lodged in a well wherein: a. said first operating means includes substantially cylindrical mandrel means adapted to be secured to and moved axially by an axially movable operating line extending to the well surface; b. said second operating means is adapted to be secured to an object lodged in said well and includes substantially tubular barrel means disposed about and radially spaced from a portion of said mandrel means; c. said fluid containing reservoir means includes inner and outer radial side walls formed by said mandrel means and barrel means respectively; d. said reservoir means further includes axially spaced, upper and lower end wall means having sliding seal means for maintaining a leakproof seal in said reservoir means while permitting relative motion between said first and second operating means; and e. said sliding seal means in said lower wall means of said reservoir means includes an annular piston means disposed between and axially movable with respect to said mandrel means and said barrel means.

Claim 12

A jarring mechanism as defined in claim 9 wherein said compression means includes: a. seat sleeve means carried by said mandrel; b. axially movable compression sleeve means disposed about and adapted to be sealingly engaged by said seat sleeve means for movement relative to said mandrel means; and c. radially distendable sleeve means included along one end portion of said compression sleeve means for distending radially into sealing engagement with said barrel means as said mandrel means is moved relative to said barrel means.

Claim 13

A jarring mechanism as defined in claim 10 wherein said variable flow passage means includes a flow path extending between annular shoulder means formed internally of said regulator sleeve means and annular shoulder means carried externally of said mandrel means whereby pressure induced, axial movement of said regulator sleeve means with respect to said mandrel means automatically moves said shoulder means into and out of engagement with each other to vary fluid flow between said shoulder means for maintaining said first pressure at substantially uniform value.

Claim 14

A jarring mechanism as defined in claim 11 wherein said variable flow passage means includes adjustable means for adjustably varying the length of said flow passage means.

Claim 15

A jarring mechanism as defined in claim 12 wherein said adjustable means includes pressure responsive wall means forming a first portion of said flow passage means for varying the cross-sectional area of said flow passage means in response to pressure changes in said fluid.

Claim 16

A jarring mechanism as defined in claim 13 wherein said adjustable means includes mating components comprising an externally threaded substantially cylindrical body received within an internally threaded regulator sleeve bore with the peaks of the threads formed on at least one of said mating components spaced from the valleys in the other of said mating components to form at least one helical flow path between said mating components, said body being rotatable within said sleeve bore for moving said body axially with respect to said sleeve bore to vary the length of said helical flow path.

Claim 17

A jarring mechanism as defined in claim 14 wherein said pressure responsive wall means includEs a bore extending axially through a threaded portion of said cylindrical body to form a tubular wall segment whereby pressure changes in said fluid move said tubular segment radially to vary the spacing between said thread peaks and valleys in said mating components.

Claim 18

A jarring mechanism comprising: a. first and second relatively movable operating means connected with each other; b. a fluid-containing reservoir included with said first and second operating means; c. compression means connected with said first and second operating means and said reservoir means for generating and maintaining a first substantially fixed pressure in a first portion of said fluid as said first and second operating means are moved relative to each other along a first portion of their relative travel, said first pressure resisting relative movement between said first and second operating means; and d. release means connected with said first and second operating means and said reservoir means for reducing said first pressure to a second, lower pressure when said first and second operating means are moved along a second portion of their relative travel to reduce the resistance to relative movement between said first and second operating means whereby a jarring blow is delivered between said first and second operating means; e. said compression means including control means for automatically regulating flow of said fluid from said first portion of said reservoir to a second portion of said reservoir for maintaining said first pressure at a substantially constant value, operation of said control means being solely dependent on differential pressure between said first and second reservoir portions.

Claim 19

A jarring mechanism comprising: a. first and second relatively movable operating means connected with each other; b. a fluid-containing reservoir included with said first and second operating means; c. compression means connected with said first and second operating means and said reservoir means for generating and maintaining a first substantially fixed pressure in a first portion of said fluid as said first and second operating means are moved relative to each other along a first portion of their relative travel, said first pressure resisting relative movement between said first and second operating means; and d. release means connected with said first and second operating means and said reservoir means for reducing said first pressure to a second, lower pressure when said first and second operating means are moved along a second portion of their relative travel to reduce the resistance to relative movement between said first and second operating means whereby a jarring blow is delivered between said first and second operating means; e. said compression means including control means for automatically regulating flow of said fluid from said first portion of said reservoir to a second portion of said reservoir for maintaining said first pressure at a substantially constant value, operation of said control means being solely dependent on differential pressure between said first and second reservoir portions.

Claim 20

A jarring mechanism as defined in claim 16 wherein said control means includes variable flow passage means for automatically varying flow path dimensions in a flow passage extending between said first and second reservoir portions.

Claim 21

A jarring mechanism as defined in claim 17 wherein said variable flow passage means includes adjustable means for adjustably varying the length of said flow passage means.

Claim 22

A jarring mechanism as defined in claim 18 wherein said adjustable means includes pressure responsive wall means forming a first portion of said flow passage means for varying the cross-sectional area of said flow passage means in response to pressure changes in said fluid.