JPS5996389A - Hydraulic fishing jar - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a new and useful improved fishing jar, and more particularly to a single-acting hydraulic fishing jar.

Fishing in oilfield terminology
means to remove from a well hole objects that do not belong to the well hole. The object to be removed is “Fish J (f
ish) is a manufacturing device that is to be removed from a stack of drill strings when drilling an oil or gas well, or from an existing wellbore at the end of oil extraction or during a repair process. The method already employed for removing the fish is to grasp the fish by some means and apply an axial strain to the means by pushing or pulling until the fish is obtained. A jar is a tool employed when perforating or manufacturing equipment is stacked so long that it cannot be removed by pushing or pulling it in a straight line above the ground.

A jar is typically placed within the drill string in the area of the stacked object so that a drilling rig operator at the surface can apply an impact force to the fish by manipulating the drill string. The jar has a spline connection that does not permit relative axial movement between the inner mandrel and the outer housing without relative rotation.

The mandrel includes an impact surface or hammer that contacts a similar impact surface or anvil on the housing when the jar reaches the limit of its axial movement. When these impact surfaces strike each other at high speeds, they create a very large impact on the fish due to the mass of the drill pipe above the jar.

Conventional jars are classified into three different types of jars: hydraulic jars, mechanical jars, and Bamba style jars. Bumper jars are primarily used to provide downward impact force. Bumper jars typically have splined connections that allow for sufficient axial movement so that the drill pipe is moved up and down and the impact surfaces inside the jar impinge upon each other and exert a downward impact force on the fish. I'm starting to get it.

Mechanical and hydraulic jars differ from bumper jars in that they include a trip mechanism that delays relative movement of the impact surfaces relative to each other until an axial strain is applied to the drill pipe. To drive the jar upward, the drill pipe is stretched by applying an axial pull at the surface. This tensile force is carried by a jar trip mechanism that is long enough to allow the drill pipe to extend and store potential energy.

When the jar is actuated, the stored energy as described above is converted to mechanical energy, which causes the impact surfaces of the jars to impinge upon each other at high velocity. Hydraulic and mechanical jars are more efficient than bumper jars because they can provide a greater impact on the fish for a given drill pipe strain.

Mechanical jars generally have less range of applications and are less reliable than hydraulic jars. In some mechanical trip mechanisms, a trip load must be selected and preset at the surface in order to operate the jar at a particular load.

If it is necessary to increase or decrease the trip load, it is necessary to pull the drill pipe out of the wellbore, a costly and time consuming procedure. In another known mechanical trip mechanism, torque is applied to the trip mechanism from the ground through the drill pipe, and the torque must be maintained during operation of the jar. This is not only dangerous for workers in the workplace;
This makes it difficult to control the trip load in the case of a wellbore that deviates from a predetermined course.

Another disadvantage of mechanical trip mechanisms is that they must be operated under a triggered condition. The trip mechanism is thus subjected to stress during normal drilling when it is operated as part of the bottom hole assembly. Furthermore, mechanical tripping mechanisms have the disadvantage that the metal parts must move relative to each other under very high compressive loads. This causes premature wear and frequent failure of the moving parts.

Hydraulic trip mechanisms are even more desirable because they allow the impact load to be arbitrarily controlled solely by the extent of the axial strain imparted at the ground surface. Additionally, hydraulic trip mechanisms are less susceptible to mechanical deformation and wear than mechanical trip mechanisms, and therefore can be used for longer periods of time under the same conditions than mechanical trip mechanisms. .

Patent documents disclosing hydraulic fishing jars have primarily been published within the past 30 years.

U.S. Pat. No. 3,349,858 discloses a single-acting (upward) hydraulic drilling jar in which the flow of crude oil past a piston is controlled by a flow control valve that provides constant flow control.

U.S. Pat. No. 3,735,827 discloses a hydraulic fishing jar that requires compressible pressure fluid. The mandrel is moved until the pressure fluid is compressed to a predetermined degree, and at the point at which the pressure fluid is compressed to a predetermined degree, the control valve engages the adjustable trip abutment, thereby causing the control valve to engage the control valve. The valve is opened and pressurized fluid is discharged through the bypass passage, thereby allowing rapid movement of the hammer relative to the anvil surface.

U.S. Pat. No. 3.797.591 includes U.S. Pat.
A hydraulic fishing jar is disclosed that includes an adjustable trigger mechanism similar to the jar disclosed in No. 735,827, but different from the trigger mechanism incorporated therein.

U.S. Pat. No. 3,851,717 has a constant flow bypass passage for the trip piston and is configured to drive the trip piston downward until the main bypass valve is opened and the jar is actuated. A hydraulic fishing jar is disclosed.

U.S. Pat. No. 4.059.167 includes U.S. Pat.
Similar to the jar disclosed in No. 851,717,
A fishing jar incorporating a tandem piston arrangement for reducing internal working pressure is disclosed.

U.S. Pat. No. 3,285.353 has two mandrels arranged in a cannula within an outer housing;
A fishing jar is disclosed in which one of the two mandrels is connected to a drill string and the other mandrel is configured to be connected to a drill fish. A piston valve is included which is configured to reduce the pressure and drive the housing to impinge the surface of the hammer against the anvil surface after a predetermined movement.

U.S. Pat. No. 3,087,559 discloses a hydraulic fishing jar having a mechanical trip finger with a hydraulic delay means.

One object of the present invention is to provide a new and improved fishing jar useful in earth drilling operations to remove accumulated objects, ie, fish, from drilled holes.

Another object of the present invention is to provide a new and improved hydraulically controlled and driven fishing jar having an improved trip mechanism.

Another object of the present invention is to provide a new and improved single-acting hydraulic fishing jar constructed to be easily returned to a re-operable condition and then re-operated in the same direction. That's true.

A single-acting hydraulic fishing jar is disclosed that is configured for use within a tubular drill string to generate an upward jarring force to remove fish from a well. The jar is configured to be inserted into a wellbore on a drill string and connected to a fish tool in the wellbore.

The fishing jar of the present invention includes an outer housing member and an inch housing member (mandrel) arranged in a large cylinder manner so as to be able to move relative to each other in the longitudinal direction, and one housing member is provided with a hammer member. , the other housing member is provided with an anvil member. The housing member defines a chamber configured to contain a fluid that controls the jarring force. One end of the chamber is closed by a slidable seal that slidably supports an inner housing member or mandrel within the outer housing member. A piston is spaced apart from the sliding seal for movement within the pressure fluid chamber relative to the active seal.

The pistons are arranged such that movement of the housing member in one direction relative to the other housing member drives the piston toward the sliding seal.

The chamber between the piston and the sliding seal has an outlet controlled by a valve element slidably supported on the mandrel. a predetermined relative movement of the housing member engages and drives the valve element to an open position;
This allows fluid to flow out of the fluid cavity and substantially eliminates resistance to further movement of the housing member, thus allowing the hammer member carried by the mandrel to move and engage the anvil member carried on the outer housing. Engagement with impact force is permitted.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

A single-acting finning jar so long that it has to be shown divided into parts in the accompanying Figures 1A to 1D,
The cross section is shown as a continuous four-part section in the longitudinal direction. In particular, Figures 1A to 1D show longitudinal half-sections from the centerline of the jar to its outer periphery. The fishing jar 1 includes a tubular inner mandrel 2 supported in a tubular outer housing 3.

The mandrel 2 and housing 3 consist of a plurality of segments, which will be explained in detail later.

The mandrel 2 includes a tubular upper member 4 having a longitudinal passage 5 therein (see Figures 1A and 1B).

The upper end of the upper member 4 is enlarged in diameter as shown at 6 and has an internal thread 7 for connection to a drill string or the like.

The lower end of the upper member 4 is provided with a counterbore that extends to the internal shoulder 8 and is internally threaded 9 .

The middle part of the mandrel 2 consists of a tubular sleeve member 10 (see FIGS. 1B and 1c), which is inserted into the upper part 4 of the mandrel with its upper end abutting the shoulder 8. It has an external thread 11 at its upper end so as to be screwed into and connected to the screw 9. The lower end of the sleeve member 1o is provided with an external thread 12 (see Figure 1C) and a passage 5 provided in the upper member 4 of the mandrel.
An internal bore or passageway 13 is provided which communicates with the.

The lower end of the mandrel 2 consists of a tubular member 14 (
1C and 1D), the tubular member has a shoulder 15
A counterbore is provided which extends up to and is internally threaded 16 . The tubular member 14 has a lower end of the sleeve member 10
The sleeve member 10 is assembled by screwing into the lower end portion of the sleeve member 10 while in contact with the portion 15 .

The lower end of the tubular member 14 is tapered, as indicated at 17, to define an annular stop shoulder 18. Tubular member 14 has a longitudinally extending internal passageway 19 in communication with passageways 5 and 13. When the upper member 4, sleeve member 10, and tubular member 14 are screwed together as shown, they constitute a single tubular mandrel 2 that is longitudinally movable within the housing s, as will be explained later. .

Like the mandrel 2, the housing 3 is made up of several sections for easy assembly. The upper end of the housing 3 is made up of a tubular member 20 (first A
(see figure), the tubular member 20 has a smooth inner bore 21 at its upper end, in which the outer surface 22 of the upper member 4 of the mandrel 2 is arranged to be slidable in the longitudinal direction. The lower end of the tubular member 20 has a reduced diameter section defining an annular shoulder 23 and having an externally threaded section 24 .

The housing 3 includes a tubular intermediate member 25 (first
(see Figure A and Figure 1B), the intermediate member includes a tubular member 20.
An internal curvature 26 is provided at its upper end for connection to the threaded portion 24 of the holder. The upper end of the intermediate member 25 comes into contact with the shoulder portion 23 when the tubular member 20 and the intermediate member 25 are tightly fastened. The lower end of the intermediate member 25 has a reduced diameter portion forming a shoulder 27 and having an external thread 28 (see FIG. 1B).

The lower part of the housing 3 comprises a tubular member 29 (see FIGS. 1B, 1C and 1D), which has an inner end at its upper end for threaded connection with the outer thread 28 of the intermediate member 25. A screw 30 is provided. The upper end of the tubular member 29 comes to abut against the shoulder 27 when the intermediate member 25 and the two tubular members are tightly fastened. An internal thread 31 is provided at the lower end of the tubular member 29 (first D
(see figure).

At the lower end of the housing 3 there is provided an elongated tubular connecting member 32 which is provided with an external thread 33 at its upper end and has a shoulder 34 . When the inner thread 31 and the outer thread 33 are tightly screwed together, a tubular member 29 is attached to the shoulder portion 34.
The bottom ends of the two are in contact with each other. The connecting member 32 has a longitudinally extending internal passageway 35 that communicates with a passageway extending within the mandrel 2 and between the tubular member 14, the tubular member 29, and the connecting member 32. It communicates with the annular space between the inner surface and the inner surface. The lower end of the connecting member 32 has a reduced diameter as indicated by the reference numeral 36, and has an external thread 37 that is connected to a fish or the like so that it can function as a fishing jar.

As previously mentioned, the mandrel 2 and the housing 3 consist of several sections that are connected to each other by threading for easy assembly. Mandrel 2 is housing 3
It is configured to be able to slide inside. The fishing jar is filled with a suitable working fluid, e.g. a pressurized fluid, as will be explained later, so that some assemblies may leak at points and points of sliding engagement between the mandrel 2 and the housing 3. Seals must be in place to prevent this from happening.

As previously mentioned, the outer surface of the upper member 4 of the mandrel 2 is slidably fitted within the bore 21 of the tubular member 20 of the housing 3. The tubular member 20 is provided with an annular groove 38 on its inner periphery, in which an O-ring 39 is arranged to seal the sliding connection to prevent leakage of pressure fluid. The threaded connection between the tubular member 20 and the intermediate member 25 is sealed by an O-ring 40 to prevent fluid leakage (see FIG. 1A). It is arranged within an annular groove 41 provided. Similarly, the threaded connection between the intermediate member 25 and the tubular member 29 is sealed against fluid leakage by an O-ring 42 (see FIG. 1B).
is an annular groove 4 formed on the outer peripheral surface of the lower end of the intermediate member 25.
It is located within 3. Also, the tubular member 29 and the connecting member 3
2 is sealed by an O-ring 44 to prevent fluid from leaking (see Figure 1D), and the O-ring 44 is disposed within an annular groove 45 provided at the upper end of the connecting member 32. ing.

Seals similar to those described above are provided to prevent fluid from leaking through the threaded connections connecting the several sections of mandrel 2.

The threaded connection between the upper member 4 of the mandrel 2 and the sleeve member 10 is sealed against fluid leakage by an O-ring 46 (see FIG. 1B). It is disposed in an annular groove 47 formed on the inner peripheral surface. Similarly, the threaded connection between the Reni sleeve part @ 10 and the tubular member 14 is sealed by an O-ring 48 to prevent fluid from leaking. 1C), the O-ring 48 is an annular groove 4 formed on the inner peripheral surface of the tubular member 14.
It is located within 9.

Inner bores of various members of housing 3 and mandrel 2
The space between the outer surface of the fishing jar provides a sealed chamber and passageway for passage of pressurized fluid (or other suitable working fluid) into the fishing jar. Various additional elements are provided as will be explained later. At the upper end of the tubular member 20, an annular chamber 52 is provided by the space between the inner bore 50 of the tubular member 20 and the outer surface 22 of the upper member 4. A screw hole 53 is provided at the upper end of the annular chamber 52, and a plug member 54 having a threaded portion is fixed to the screw hole. Threaded holes 53 provide a means for introducing pressurized fluid (or other suitable working fluid), as will be explained later.

The outer surface of the upper member 4 is slightly reduced in diameter at its lower end 55 and is provided with a plurality of longitudinally extending grooves 56 between which splines 57 are defined. (See Figures 1A and 2). The lower end of the tubular member 20 is provided with a reduced diameter inner bore 58 defining an angled upper shoulder 59;
It also has a plurality of longitudinally extending and circumferentially spaced grooves 60 defining a plurality of splines 61 that fit into the grooves 56 provided in the upper member 4. (See Figures 1A and 2).

The grooves 56 provided in the upper member 4 and the grooves 60 provided in the tubular member 20 have splines 5 disposed within those grooves.
The depth is greater than the height of 7 and 61. Accordingly, passages are defined extending longitudinally within the respective grooves provided in the upper member 4 and the tubular member 20, as indicated at 62 and 63 in FIGS. 1A and 2. ing. By providing longitudinally extending splines and grooves in the upper member 4 and the tubular portion '4'A20, a guide is formed for the mandrel 2 to move longitudinally within the housing 3 without rotational movement thereof. has been done.

Passages 62 and 63 formed in the gaps between splines 57 and 61 and grooves 56 and 60 provide a means for pressurized fluid to flow between chamber 52 and the lower portion of the fishing jar, as will be explained later. ing.

As shown in FIG. 1B, the gap between the intermediate member 25 and the upper member 4 defines a fluid pressure chamber 64 that is substantially larger in size than the fluid pressure chamber 52 and that communicates with the fluid pressure chamber 52. It is a gap like that. The lower end of the tubular member 20 has an anvil surface 65 that is used when the illustrated fishing jar is moved upwardly to lift objects from the well. The inner surface 66 of the intermediate member 25 defines a counterbore that defines a circumferentially extending shoulder 67 that is a stop for limiting downward movement of the mandrel within the housing. It is defined at the lower end of 64.

The lower end 68 of the upper member 4 has an outer surface 55 with a threaded portion 69.
have. A hollow cylindrical hammer 70 having an internal thread 71 is fixed by screwing into the six threaded parts of the upper member 4, and is fixed by fixing screws (not shown) so that it will not loosen even during operation of the device. It's good that it has been done.

The upper end 72 of the hammer 70 is engageable with the anvil surface 65 of the tubular member 20 during operation of the fishing jar.

The lower end surface 73 of the hammer 70 engages the shoulder 67 when the fishing jar is at the limit of its downward travel.

Intermediate member 25 has an upper counterbore 74 and a lower counterbore 75 extending to positions spaced a short distance apart from each other.
and defines an intermediate member 76 that constitutes a guide for guiding the movement of the mandrel.

The sleeve member 10 has a plurality of grooves 7 extending in the longitudinal direction.
7 (see FIG. 1B, FIG. 1C, and FIG. 3). Groove 77 defines a passageway for passage of pressure fluid as will be explained later. A tubular sleeve member 78 is tightly fitted into the sleeve member 10 and overlaps the upper end of the groove 77 . The lower end of the sleeve member 78 has an enlarged diameter portion 79 whose sloping surface aligns with the valve seat 8.
0 (see Figures 1B and 3).

Sleeve member 78 has a counterbore 74 at its upper end.
A hole 81 is provided to communicate and connect the groove 77 and the groove 77 . Further, the sleeve member 78 is provided at its lower end with a hole 82 that communicates with the lower part of the groove 77 and the fluid pressure chamber 83 and is controlled by a trip valve 84 which will be described later. The upper end of the sleeve member 78 is in contact with the lower end of the upper member 4.

The lower end of the sleeve member 78 located below the valve seat 80 (
The upper end of the tubular sleeve member 85 is in contact with the upper end of the sleeve member 85, and the sleeve member 85 is tightly fitted into the sleeve member 10 to form the groove 7.
It covers the lower end of 7. Sleeve members 78 and 85 thus seal groove 77 and define a series of longitudinally extending passageways. The lower end of the sleeve member 85 is enlarged in diameter as indicated by reference numeral 86, and has a plurality of holes 87 communicating with the lower end of the groove 77.

The inner surface 88 of the tubular member 29 and the outer surface of the sleeve member 78.85 are spaced apart from each other to define a fluid pressure chamber 83. The outer surface of sleeve member 85 is a smooth cylindrical surface to allow free movement of pressure piston 89, and trip valve 84 is supported therebetween.

The lower end of the sleeve member 85 has an enlarged diameter as shown at 90, and a groove 91 is provided on its outer surface. The upper end of the fluid pressure chamber 83 is connected to the guide portion 7 of the intermediate member 25.
6 is sealed by an O-ring 92 disposed within an annular groove 93.

A trip valve 84 that controls the flow rate of the pressure fluid flowing out from the fluid pressure chamber 83 is disposed approximately in the center of the fluid pressure chamber 83 (see FIGS. 1B and 5C). Trip valve 84 is a tubular valve element having a smooth cylindrical bore 94 that slidably fits along the outer surface of sleeve member 85.

The trip valve 84 is sealed on its inner surface by an O-ring 95 disposed within an annular groove 96.

Trip valve 84 has an enlarged tubular extension 97 having a counterbore 98 . The counterbore 98 is connected to the fluid pressure chamber 83 by a hole 99 . The trip valve 84 has a sloped valve seat surface 100 connecting a smooth cylindrical bore 94 and a counterbore 98, the valve seat surface 100 abutting the valve seat 80 when the trip valve 84 is in the m-valve position. It is designed to be in contact with each other.

An annular pressure piston 89 is arranged at the lower end of the fluid pressure chamber 83 (see FIG. 1C). The piston 89 is slidably disposed between the sleeve member 85 and the inner surface 88 of the tubular member 29 and is sealed on its outer surface by an O-ring 101 disposed within an annular groove 102. The piston 89 has a longitudinally extending passageway 1.3 with an orifice 104. A groove 91 is formed in the enlarged diameter portion of the sleeve member 85, and the piston 89 is adapted to slide over the groove 91 to allow flow of pressurized fluid. Between the piston 89 and the trip valve 84, a shoulder portion 107 is provided which urges the trip valve 84 to the closed position.
A compression coil spring 106 is disposed to bias the spring 106 to an initial position where it abuts the spring 106 .

A fluid chamber 108 is defined by the outer surface 109 of the tubular member 14 and the inner surface 110 of the tubular member 29 below the shoulder 107 that the pressure piston 89 contacts (see FIG. 1C).
. The lower end of the fluid chamber 108 is closed by an annular piston 111 slidably disposed within the fluid chamber. Piston 111 is sealed against fluid leakage by O-rings 112 and 113 disposed within annular grooves 114 and 115, respectively. The piston 111 is connected to the connecting member 32
It comes into contact with a spring 116 supported on the upper fM117 and is biased upward by the spring. A threaded hole 118 closed by a plug 119 provides means for filling the fluid chamber 108 with fluid.

However, the above-described device is a single-acting hydraulic fishing jar that may be used to apply an upward impact force, ie, jarring force, to objects, ie, fish, stacked in a well. In operation, when the fishing jar generates an upward impact force, an axial tensile force is applied to the drill pipe at the surface, thereby elongating the drill pipe.The resistance to such tensile force is
The drill pipe is extended and provided by a jar tripping mechanism long enough to store potential energy. When the jar reaches the trip position, the energy stored in the extended drill pipe is converted into mechanical energy that drives the impact surfaces of the jar, i.e., the hammer and anvil, toward each other and impinges at high velocity. , which gives a very high impact force. When the upward extension of the drill pipe is released, the jar is returned to its initial or starting position. The device described above is a novel upward-acting fishing jar and is actuated by hydraulic pressure. In order to make the invention easier to understand, the operating principles and order of movement of the various members will be explained.

LLl When the fishing jar 1 is assembled as described above, the jar will fit through the hole 53 provided in the tubular member 20 and the tubular member 2.
It is filled with pressure fluid through holes 118 arranged at 9. Preferably, the pressure fluid used is an incompressible fluid since the jar operates by exploiting the leakage of fluid past the pressure piston. The fishing jar may be operated using wellbore fluid, since the spacing between the members during operation can be adjusted to a certain degree. The working fluid is preferably an incompressible fluid, but compressible pressure fluids or high pressure gases may also be used.

However, in this case, the travel distance required to pressurize the compressible fluid is greater, so a longer tool is required.

Pressure fluid passes through holes 53 and 118 to the fishing hole 1-
-1, the pressure fluid is introduced into the pressure piston 111
The fluid flows to the bottom of the fluid chamber 108, which is closed by the fluid chamber 108. The pressure fluid flows through the space within the fluid pressure chamber 108 and the pressure piston 89.
The space within the fluid pressure chamber 83 provided between the O-ring 92 and the O-ring 92 is filled.

Pressure fluid also fills various passageways, including passageway 77 and counterbore 74 leading to fluid pressure chamber 64 .

Further, the fluid pressure chamber 64 and the fluid pressure chamber 52 are filled with pressure fluid up to the height of the hole 53.

The fishing jar may be tilted to some extent to remove any air bubbles present in the pressure fluid, thereby filling the fishing jar completely with pressure fluid up to the holes 53. At this point, plugs 54 and 119 are inserted and the fishing jar is ready for use. The pressure screws 111 allow thermal expansion of the fluid and the static pressure of the fluid in the wellbore and surrounding the jar allows the pressure fluid to flow completely from one section of the jar to another. Make it possible to maintain the pressure fluid in the jar under sufficient pressure.

In the embodiment shown in Figures 1A-1D, the jar is in its initial or starting position, and the jar is initially positioned to create an upward impact force that facilitates loosening the fish. driven upwards from the position. In this initial position, the hammer 70 is in contact with the shoulder 73. The pressure piston 89 is maintained in contact with the shoulder 107 by the spring force of the spring 106. In this initial position, the spring 106 keeps the trip valve 84 in contact with the valve seat 80 in the IC closed position (see FIG. 1B). Next, the operation of the fishing jar of the present invention to generate an upward impact force to loosen a fish will be explained.

When the upward jarring fishing gear 17-1 is actuated upward from the initial position shown in FIGS. 1A to 1D, the drill pipe to which the upper end 6 of the mandrel 2 is attached is extended upward;
brought to the desired state of tension. When the drill pipe is stretched upward, the mandrel 2 is also brought into tension,
Move upward to the limit allowed by the trip mechanism.

When the mandrel 2 is moved upwardly from the initial position shown in FIGS. 1A-1D, the shoulder of the enlarged portion 86 of the sleeve member 85 first comes into engagement with the lower end of the pressure piston 89. In this position, the enlarged diameter portion 8
The shoulder 6 and the piston 8 function as a valve that closes one end of the fluid pressure chamber 83, thereby allowing the fluid pressure air 83 to flow through the passage 1.
Pressure fluid is prevented from flowing through parts other than 04.

Thus, upward movement of mandrel 2 does not initiate actuation of trip valve 84 and does not impart pressure to the pressurized fluid within the jar.

As the mandrel 2 moves further upwards, the shoulders of the enlarged portion 86 drive the eight pressure pistons upwards, applying pressure to the fluid within the fluid pressure chamber 83.

As the movement of the mandrel 2 drives the pressure piston 89 further upwards, a resistance to the movement of the mandrel is created since the pressure fluid filling the hydraulic cavity 83 is substantially incompressible. When the pressure piston 89 moves upward, pressure is applied to the fluid in the fluid pressure chamber 83, and the pressure of the fluid in the fluid pressure chamber suddenly becomes very high.The pressure fluid flows past the O-ring 92. and cannot flow past the trip valve 84, which is closed at this stage of operation. This allows the pressure piston 89 to move upwards at a speed determined by the amount of fluid leaking from the fluid pressure air 83 via the passage 1O3. During the movement to the mandrel 2, the pressure fluid in the fluid pressure chamber 83 is maintained under a very high pressure representing the pressure generated by the tension applied to the mandrel 2 by the drill pipe.

Further upward movement of mandrel 2 drives pressure piston 89 relative to tubular member 29 and O-ring 92. Such movement is enabled by fluid in pressure chamber 83 slowly leaking into chamber 108 through orifice 104 and past O-ring 92 through passageway 77 into cavity 64. . mandrel 2
After the predetermined uppermost movement, the fishing jar reaches a position where the upper end of the enlarged diameter portion 97 of the trip valve 84 engages the lower end 120 of the intermediate member 25. Although this position is not shown in the figure, it is an intermediate position immediately before the trip valve 84 is driven.

At this point, the pressure fluid within the fluid pressure chamber 83 is under very high pressure and resists the movement of the pressure piston 89;
This prevents the movement of the mandrel 2, which creates a substantial amount of tension in the mandrel and the drill pipe. When mandrel 2 moves further upwards,
Movement of the trip valve 84 together with the mandrel is restricted, and the valve seat surface 100 of the trip valve 84 moves in a direction away from the valve seat 80 to open the trip valve 84.

In this position, the enlarged portion 9 of the trip valve 84
The upper end of 7 is in contact with the lower end 120 of the intermediate member 25.

Trip valve 84 is opened and pressurized fluid flows through holes 99 and 82.
through which the various passageways flow freely through the other fluid chambers 108.6.
It communicates with 4.52.

When the trip valve 84 is opened, the fluid in the fluid pressure chamber 83 starts to flow to other fluid chambers, mainly the fluid chambers 108 and 64, and the pressure in the fluid pressure chamber 83 becomes equal to the level of the static pressure in the wellbore. It drops significantly to .

This pressure drop removes the resistance to upward movement of the pressure piston 89, and the pressure piston 89 and mandrel 2 move rapidly through the remainder of the jarring stroke.

Such rapid movement of the pressure piston 89 and mandrel 2 is the movement between the position where the trip valve 84 begins to open and the position shown in Figures 5A-5D. This movement causes the trip valve 84 to be wide open and the top surface 72 of the hammer 70 to be opened as shown in FIGS. 5B and 5C.
This is the movement when the mandrel 2 moves upwards to the point where it engages the anvil surface 65. The above-described rapid movement of the mandrel 2 and pressure piston 89 transfers the tensile energy in the mandrel 2 and the drill pipe to the hammer 7.
0 is released in the form of mechanical energy that drives it at high speed to collide with the anvil surface 65. At the time hammer 70 engages anvil surface 65, the fishing jar reaches its limit of upward movement. Thus, upward movement of the mandrel 2 is limited by the engagement of the hammer 70 with the anvil surface 65, and downward movement of the mandrel 2 is limited by the engagement of the hammer 70 with the shoulder 67, as described above. .

When the fishing jar reaches the limit of its upward movement shown in Figures 5A to 5D, the fishing jar releases the tension on the drill pipe and the mandrel 2 moves to the initial position after upward jarring. It is returned to a state in which it can be operated again by allowing it to return to the initial position shown in FIGS. 1A to 1D. When the mandrel 2 moves downward, the hammer 70 moves away from the anvil surface 65. In this case, the pressure piston 89 moves downwards together with the mandrel 2. The fluid pressure chamber 83 is filled with pressure fluid that is forcibly passed through the hole 87, the passage 77, the hole 82, and the trip valve 84 which is in the open state as the pressure piston 89 moves downward. As the mandrel 2 moves downward, the trip valve 84 closes to the end 1 of the intermediate member 25.
20, thereby closing the trip valve 84. As the downward movement of the mandrel 2 continues, the pressure piston 89 contacts the shoulder 107 and the valve formed by the pressure piston 89 and the enlarged diameter portion 86 of the sleeve member 85 opens. The static pressure acting on the piston 111 forces the pressure fluid through the opened valve into the fluid pressure chamber 83, thereby ensuring that the fluid pressure chamber 83 is filled with pressure fluid. The initial position shown in FIGS. 1A-1D, where further downward movement of the mandrel 2 causes the hammer 70 to engage the shoulder 67, thereby preventing further downward movement of the mandrel 2. Pressure fluid is distributed between fluid chamber 108 and fluid chambers 52 and 64 until the fishing jar is returned.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited to such embodiments, and it is understood that various embodiments are possible within the scope of the present invention. It will be clear to those skilled in the art.

[Brief explanation of drawings]

FIGS. 1A to 1D are half-sectional views showing an embodiment of the single-action hydraulic fishing jar according to the present invention divided into four parts in the longitudinal direction, respectively, in an initial position. FIG. 2 is a cross-sectional view of a half-section of the finning jar taken along line 2--2 of FIG. 5B. FIG. 3 is a cross-sectional view showing a half section of the fishing jar along line 3-3 of FIG. 5B. FIG. 4 is a cross-sectional view of the fishing jar half section taken along line 4--4 of FIG. 5C. Figures 5A-5D show the position of the fishing jar after the trip valve has been opened, the mandrel has completed its upward movement, and the hammer has impacted the anvil portion. FIG. 3 is a corresponding half-sectional view. 1...fishing v-, 2-...mandrel, 3
... Housing, 4... Upper member, 5... Passage,
7... Internal thread, 8... Shoulder, 9... Internal thread, 10
... Sleeve member, 11... Threaded portion, 12... External thread, 13... Passage. 14... Tubular member, 15... Shoulder, 16... Internal thread, 18... Shoulder, 19... Passage, 20... Tubular member, 21... Inner bore, 22...・External surface, 23・
... Shoulder part, 24... Threaded part, 25... Intermediate member, 2
6... Internal thread, 27... Shoulder, 28... External thread,
29... Tubular member, 30. 31... Internal thread, 32.
... Connection member, 33 ... Outer thread U, 34 ... Shoulder part, 3
5... Passage, 37... External thread, 38... Annular groove,
39.40...0 ring, 41...annular groove, 42...
... O-ring, 43... Annular groove, 44... O-ring, 45... Annular groove, 46... O-ring, 47-...
Annular groove, 48... O ring, 49... Annular iR, 5
0...Inner bore. 52... Empty, 53... Hole, 54... Plug member,
55... Lower end, 56... Groove, 57... Spline, 58... Inner bore, 59... Shoulder, 60...
・Groove, 61... Spline, 62.63... Passage,
64... Fluid pressure chamber, 65... Anvil surface, 66...
・Inner surface, 67...Shoulder, 68...Lower end, 69...
・External thread, 70... Hammer, 71... External thread, 72
. . . upper end portion, 73 . . . lower surface, 74 . . . upper counter bore, 75 . . . lower counter bore, 76 .
... Enlarged diameter portion, 80... Valve seat, 81. ．． 82・
...hole. 83...Fluid pressure air, 84...Trip valve, 85...
- Sleeve member, 86... enlarged diameter portion, 87...
- Hole, 88...Inner surface, 89-...Pressure piston, 91
...groove, 92...0 ring, 93... annular groove, 9
4... Bore, 95... O-ring, 96... Annular groove, 97... Extension part, 98... Counter bore, 99...
...hole, 100...valve seat surface, 101...0 ring,
102... Annular groove, 103... Passage. 104... Orifice, 106... Compression coil spring. 107...shoulder part, 108...fluid chamber, 109...
Exterior. 110...Inner surface, 111...Piston, 112.1
13... O ring, 114.115... Annular groove, 1
16...-Spring, 117...-Upper end, 118...Threaded hole patent applicant Hughes Tool Company representative
Patent Attorney Akira - Masaru Ishifig, 573

Claims (3)

[Claims] (1) a pair of tubular members arranged in a cylindrical manner for limited longitudinal movement of each other relative to each other in a fluid-operated fishing jar, one tubular member connected to a drill pipe; a pair of tubular members, the other tubular member being configured to connect to an object to be removed from the well; means for defining a chamber between the tubular members; a piston means operatively connected to and configured to be driven by the piston means; said chamber being configured to be filled with a fluid resisting relative movement of said piston means; one of the tubular members is adapted to move in one direction without exerting pressure on the fluid within the chamber when the tubular members move in one direction relative to each other; a valve hole disposed between said chamber and one end of said chamber, said valve hole being initially closed and said piston means being moved in said first predetermined relative movement in said one direction; valve means configured to move to open the valve hole to release fluid from the chamber, thereby substantially reducing resistance to further relative movement of the piston means and relative movement of the tubular member; means for allowing a relatively small flow of fluid from the chamber during the first predetermined relative movement of the piston means, which engages with a jarring impact during the further relative movement of the tubular member; A fluid-operated fishing jar comprising: a hammer and anvil means that are compatible; (2) a fluid-operated fishing jar defining radially spaced, longitudinally extending chambers arranged in a cannula for limited longitudinal movement relative to each other; an inner tubular member and an outer tubular member; a sealing means disposed between the tubular member and defining one end of the chamber; and a sealing means disposed between the inner tubular member and the outer tubular member in a longitudinal direction from the sealing means. piston means spaced apart from each other, the piston means being movable relative to the sealing means and defining the other end of the chamber; and the chamber containing a fluid resisting relative movement of the piston means. means for driving said piston means toward said sealing means in response to relative movement in one direction between said tubular members; a valve hole disposed between the means and the sealing means; and when the valve hole is initially closed and the piston means makes a first predetermined relative movement in the one direction; valve means configured to move to open the valve hole to release fluid from the chamber, thereby substantially reducing resistance to further relative movement of the piston means and relative movement of the tubular member; , means for allowing a relatively small flow of fluid from the chamber during the predetermined relative movement of the piston means, and means for engaging with a jarring impact during the further relative movement of the tubular member; a fluid-operated fishing jar comprising: hammer and anvil means for obtaining; (3) single-acting hydraulic fishing jars configured to be connected within a tubular earth drill string, with outer shells arranged in a cannula-like manner to permit limited longitudinal movement of each relative to the other; a tubular member and an inner tubular member; means defining an outer chamber for storing fluid therebetween including the tubular member and sealing means cooperating therewith; another sealing means and piston means spaced apart from each other and defining an inch chamber within the outer chamber; and in response to relative movement of the tubular member in one direction, the piston means moves the piston means into the other direction. means for driving the piston means toward the other sealing means; said outer chamber and said inner chamber being filled with a pressurized fluid to resist relative movement of said piston means toward said other sealing means; and a means for allowing a small amount of fluid to flow from the inner chamber, and when the inner chamber and the outer chamber are filled with fluid, the piston means and the other seal means for allowing relative movement between said piston means and said other sealing means, at least one passageway for allowing fluid to flow from said inner chamber to said outer chamber; a valve means disposed within the inner chamber to close the passage; and a valve means actuated to open the valve means when the tubular member makes a predetermined relative movement in the one direction, thereby allowing passage from the inner chamber to the outer chamber. valve actuation means for permitting fluid flow to substantially reduce resistance to relative movement of said tubular member; further relative movement of said tubular member after opening of said valve means is accompanied by a jarring impact; A single-acting hydraulic fishing jar comprising: a hammer and anvil means configured to engage each other;