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Publication numberUS2721056 A
Publication typeGrant
Publication dateOct 18, 1955
Filing dateFeb 14, 1952
Priority dateFeb 14, 1952
Publication numberUS 2721056 A, US 2721056A, US-A-2721056, US2721056 A, US2721056A
InventorsStorm Lynn W
Original AssigneeStorm Lynn W
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Hydraulic well jar
US 2721056 A
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Description  (OCR text may contain errors)

Oct. 18, 1955 w. STORM HYDRAULIC WELL. JAR

4 Sheets-Sheet 1 Filed Feb. 14, 1952 W Jform INVENTOR Lynn ZZQKWJ ATTORNEY Oct. 18, 1955 1.. w. STORM HYDRAULIC WELL JAR 4 Sheets-Sheet 2 Filed Feb. 14, 1952 [507/7 l V. Jfo/"m l N VEN TOR.

A 7 TOR/V5) Oct. 18, 1955 w STORM 2,721,056

HYDRAULIC WELL JAR TTOR/VE Y United States Patent HYDRAULIC WELL JAR Lynn W. Storm, Houston, Tex.

Application February 14, 1952, Serial No. 271,473

7 Claims. (Cl. 25527) This invention relates to a hydraulic well jar, and more particularly to a jarring tool for use in the removal of a stuck object in the bore of a well and in which a liquid is employed for controlling the action of the tool.

The invention finds particular application in jarring tools of the hydraulic type, having inner and outer concentrically arranged tubular parts movable longitudinally relative to each other and forming between them a closed fluid chamber. The outer part, or barrel, in jars of this type, is provided with a portion of restricted internal diameter within the fluid chamber, and the inner part, or mandrel, carries a piston which is movable into and out of the restriction, the annulus of the piston being slightly smaller than the internal diameter of the restriction to permit the flow of liquid past the piston as the piston moves in the restriction.

In the use of jars of this type, the outer part, or barrel, may be connected to an operating string, while the inner part, or mandrel, may be connected to an object stuck in the bore of a well, and upon upward or downward movement of the operating string, the parts are moved longitudinally relative to each other, the liquid in the chamber flowing past the piston during such movement. Upon movement of the piston into the restriction, however, the flow of liquid past the piston is restricted, so that further relative movement of the parts takes place very slowly, resulting in the development of tension or compression in the operating string, depending upon whether the same is being moved upwardly or downwardly. As soon as the piston moves out of the restriction, however, the relative movement of the parts is no longer restrained, and the parts move suddenly to the limit of their relative movement to produce a jarring action.

Jars of this type may be used to produce a jarring action either upwardly or downwardly, and in the event it is desired to operate such a jar to carry out a jarring action in one direction only, either upwardly or downwardly, the difliculty is encountered that the parts must be moved relative to each other in the opposite direction to bring them to position to initiate a jarring stroke, and such return movement of the parts can take place only very slowly as the piston makes its return movement in the restriction, thus greatly slowing the jarring operation.

In the use of such tools the fluid chamber is customarily filled completely with a suitable liquid, such as oil, and any loss of liquid due to leakage results in the entrance of air into the chamber, which may adversely affect the operation of the tool, in that it interferes with the hydraulic action of the same, and continued operation of the tool in such condition often results in the formation of an undesirable emulsion with the oil. The construction of such a tool having a fluid chamber which is adapted to be completely filled with liquid also presents a diflicult problem in that the inner and outer parts must be so formed that no change in the volume of the fluid chamber will take place upon relative longi- ICC tudinal movement of the parts. A slight variation in the volume of the fluid chamber, brought about upon relative longitudinal movement of the parts, may result in the production of a tool which does not operate properly or in which the packing between the moving parts is subjected to excessive pressures, causing leakage of the liquid, or permitting the entrance of air into the fluid chamber.

The present invention has for its principal object the provision of a jarring tool of the type referred to in which the above disadvantages are overcome, and in which means is provided for the relatively rapid movement of the piston in the restriction, upon relative longitudinal movement of the inner and outer parts in one direction, in order to permit a rapid movement of the parts to place the tool in condition for jarring operation upon relative movement of the parts in the other direction.

Another object of the invention is to provide a jarring tool of the hydraulic type, having inner and outer telescopically arranged tubular parts movable longitudinally relative to each other, and forming between them a closed liquid chamber, the outer parts having a portion of reduced internal diameter forming a restriction in the chamber, and the inner part carrying a piston whose annulus is slightly smaller than the restriction, there being compressible means within the chamber responsive to the pressure of the liquid therein, to permit the piston to have unrestrained movement in the restriction, upon relative longitudinal movement of the parts in one direction.

Another object of the invention is the provision of a jarring tool of the type referred to wherein a compressible fluid is utilized within the liquid chamber which is responsive to pressure developed in the liquid in the chamber to permit relatively unrestricted movement of the piston in the restriction, upon relative longitudinal movement of the parts in one direction, and means is provided for maintaining the compressible fluid out or contact with the liquid in the chamber to prevent intermingling of the fluid with the liquid.

A further object of the invention is to provide a jarring tool of the hydraulic type, constructed as described above, and embodying means responsive to the pressure of the liquid in the fluid chamber, upon relative longitudinal movement of the parts in one direction, to permit movement of the piston in the restriction in said one direction more easily than in the other direction, said means being eifective to cause a flow of liquid through the restriction in the other direction, upon movement of the piston out of the restriction in said one direction.

Another object of the invention is the provision of a jarring tool constructed with inner and outer concentrically arranged tubular parts movable longitudinally relative to each other, and forming between them a closed fluid chamber, the outer part having a portion of reduced internal diameter forming a restriction within the chamber, and the inner part carrying a piston whose annulus is slightly smaller than said portion of reduced diameter, there being means in the chamber responsive to variations in the volume of the chamber at one side of the restriction, to allow the piston to have relatively unrestricted movement in one direction in the restriction.

A further object of the invention is the provision of a jarring tool of the type referred to, which is of simple design and rugged construction, capable of long Withstanding the severe conditions of use to which such an object is customarily subjected.

The above and other objects and advantages of the invention will best be understood from the following detailed description, constituting a specification of the same.

7 when taken in conjunction with the annexed drawings,

cross section, of the upper portionof a :jarin accordance with the "invention;

Figure 2A is a fragmentary 'elevational view, partly in cross section, of the lower portion ofthe same;

Figure 3 is a cross-sectional view taken along the line 3-3 of Figure 2, looking in thedirection indicated 'by the arrows;

Figure 4 is across-sectional view taken-along theline of 4-4 of Figure 2A, looking inthe direction indicated by the arrows;

Figure 5 is a-fragmentary vertical cross-sectional view on a somewhat enlargedscale, showing details of construction of a-prefe'rred form of the invention;

' Figure 6 is a fragmentary elevational view, :partly in cross section, illustrating a somewhat different form of the invention;

Figure Tis a .view similar to that of Figure 6, illustrating another formof'the invention;

Figure 8 is a view similar to'that of Figure 5, ing a further different form of the invention;

Figure 9 is a view similar to that of Figure 2, illustrating a furtherdifferent form of the invention; and

Figure 10 is a view similar to that of Figure 6, illustrating a somewhat modified form of the invention.

Referring now to the drawings in greater detail, the jar comprises inner-and outer telescopically arranged'tubular parts indicated generally at 1 and 2, respectively, which parts are movable longitudinally relative to each other, and form between them a closed fluid chamber 48.

illustrat- The outer part'is conveniently made up of an upper tubular coupling member 10, and intermediate barrel section 12 and a lower tubular member '14, and the inner part is made up of upper and lower tubular mandrel sections 16 and 18, respectively. The lowerend of the lower'mandrel section 18 is externally threaded, as indicated at 20, for the attachment thereto of a lower coupling member 22, which is-provided with an internally threaded box portion, as indicated at 24, by which the inner partof'the tool is attached to the upper end of a lower section 26 of the operating string, or'other device below the jar.

At its upper end the upper'coupling rnemberIlO has an externally threaded endportion 28, by which this member may be attached to the lower end of a section '30 of an operating'string, and at its lower end 'the upper coupling member has a reduced extern'ally'threaded portion 32, by which it is threadably attached to the upper end of the barrel 12. The lower end of the upper-coupling member is also inwardly thickened, as indicated at 34,'and is provided with inwardlyopening, annular, internal grooves 36, within which sealing means, such as'O- rings 38 are received, to form a fluid tight seal between the upper coupling member and the upper mandrel section 16. p

The lower tubular member 14 has a reduced, externally threaded, upper end portion 40, by which this member is threadably attached to the lower end of the barrel 12, and the lower end of the member 14 is inwardly thickened, as indicated at 42, and is provided with'inwa'rdly opening, annular internal grooves 44, for the reception of seal ing means, such as O-rings 46, which form a fluid tight seal between the member 14 and the lower mandrel section 18.

'Betweentheinner and outer tubular parts, and extending from the sealing means 38 in the upper coupling member to the sealing means 46 inthelower tubular member 14 there is a closed fluid chamber 48, which is normally intended to be filled with 'asuitable liquid, such as oil. The barrel section'12 has an-inwafdly thickened portion 4 50, providing .an annular restriction in the chamber 48, for a purpose later to be made apparent.

The upper and lower mandrel sections 16 and 18 are threadably connected together, as indicated at 52, and the lower mandrel section has an exteriorly thickened annular portion 54, forming an upwardly facing shoulder 56, upon which an annular member 58 is seated, the lower end 60 of the upper mandrel section being engageable with the member 58, to retain the same in position on the mandrel. The member 58 is conveniently formed with an internalannular groove 62, for the reception of suitable *seal'ingme'ans, such as an D ring 64, forming a fluid tight seal between the member .58 and the mandrel.

The member 58 forms a piston onthe mandrel, which is I adapted to move into and out of the restriction 50, upon relative longitudinal movement of the inner and outer parts.

With the par'ts'assembled asshown, it will be apparent that upon relativ'e longitudinal movement of the sinner and outer parts, when the piston 5'8 enters the restriction 'flow of liquid in thechamber froni one side to -the other :side of the restrictio'n will be restricted, and the rate of "relative longitudinal :movement between the innerand outer parts will depend' upon the amount-of 'cl'earthe exertion of a downward :force on the operating string will result :in forcing the liquid in the chamber slowly from -one side "of the restriction to the other side thereof past the piston, thus building up a'cornpressive force in the operating string while the piston moves slowly through the restriction. As soon asthe piston moves :out of the restriction, however, the liquid in 'thie ch'amber may move freely past the pistongand th'e inn'er and =ou't'er parts may move rapidlyrela'tive to .each other. The piston 58, may, if desired, have a restricted duot 59 le'ading from the upper to the lower side thereof, as s'e'e'r'r in Figure .2, whereby liquid may flow fr'o'm 'one side 'of-the piston to the other as the piston moves in there'st'riction.

The flower'end of th'elower tubular member l'4 'h'as a contact 'face '98 on :the outer :part, which is engageable ternal splines 68 fornied on thelowenmandreI'section 18,

whereby relative rotation ofth'e inner' and outer parts is prevented. The exteriorly thickened annular-por'tion :54 ofthe lower mandrel section 1 8 has a lower face 102, shown in Figure -2, which :i's=engage'able" with the'upper ends 104 of the splines 66 of the barrel 12 as seen in Figure 2A, -to produce an upward ":jarrin'g action in the operation of thetool.

As best seen in Figures 2., 3 and '5, the barrel 12 also has an inwardly thickened portion 70, providing an upwardly facing annular shoulder 72, and in the'preferred form of the invention, as :best seen in Figures 2 and 5, there is an annular casing 74, preferably formed of metal or o'ther relatively rigid material, surr'ounding 'the'upper mandrels'ection 1'6, Within'the ba'rrel 1 2, and ine'enga'gement with the shoulder 72 therein. :In order to securely maintain the casing against longitudinal movement in the barrel tlie slower end 'surfa'ce'bf t'he upper-coupling member 10 may engage the upper surface'ofthe easing to'hold the same againstthe shoulder 72. The casing '14 is of hollow construction, and enclosed within the casing there is a hollow member 76, in the 'form' of aclosed container of flexible material, filled with compressible materiahsuch asair. The casing '74 is also 'provided'with openings 78, communicating with the interior of the casing and also with the chamber 48, whereby liquid in the chamber may enter the casing.

During the operation of the tool, theexertion'of an upwardpull on the'operating string will result in *moving the barrel longitudinally upwardly relative to the mandrel, so that when the piston 53 enters the restriction 59 the flow of liquid in the chamber from one side of the piston to the other side thereof will be restricted, resulting in a building up of tension in the operating string, until the piston moves out of the restriction, whereupon the flow of liquid past the piston will be unrestricted and the barrel will move suddenly upwardly relative to the mandrel, until the lower surface 102 of the piston engages the upper end 194 of the spline 66 of the barrel to cause an upward jarring action. After the occurrence of an upward jarring action of the tool, as just described, the operating string may be lowered, whereupon the barrel 12 will move downwardly relative to the mandrel and the piston 53 will move in the opposite direction through the restriction 55 As soon as the piston 58 enters the restriction the fiow of liquid past the piston is retarded, resulting in a building up of the pressure within the fluid chamber above the restriction, which pressure causes liquid to pass through the openings 78 in the casing 74, thus compressing the container 76, so that the movement of the piston in the restriction is retarded only by the resistance due to the compression of the container 76, and the barrel may readily move downwardly over the mandrel to the limit of its downward movement relative thereto. Thus the parts may be quickly brought to position to initiate a further jarring operation of the tool. As soon as the piston moves out of the restriction on the return movement of the parts just described, the pressure built up in the flexible container 76 will immediately return the liquid through the opening 78 to the fluid chamber, thus immediately restoring the liquid in the chamber to a condition to eiiect another jarring action.

in the form of the invention illustrated in Figure 6, the upper coupling member is formed with a downwardly extending sleeve-like portion 8! spaced radially inwardly of the barrel 12. At its lower end the sleevelike portion St is externally threaded and has a nut 82 threaded thereon, providing an upwardly facing shoulder 84, opposite the shoulder 72 on the barrel. An annular space 86 is formed between the sleeve-like extension 80 and the barrel 12, which space provides an annular compartment or cylinder 86, closed at one end and opening at its other end into the fluid chamber 43, and in this cylinder an annular piston 88 is disposed for longitudinal movement. The piston 88 is provided with suitable packing, as indicated at 92, forming a fluid tight seal between the piston and the inner surface of the barrel 12. A coil spring, 94, or other equivalent resilient member is disposed in the space 86, hearing at one end against the upper coupling member 10, and at the other end against the piston 83, to urge the piston toward the shoulders 72 and 84. In this form of the invention, any increase in pressure in the chamber above the restriction, upon operation of the tool, will result in the liquid in the chamber 48 exerting a pressure against the piston 88, to move the same longitudinally in the space 86 against the action of the spring 94.

Upon movement of the barrel 12 to bring the piston 58 above the restriction, the liquid may move freely past the piston, and after the piston has moved out of the restriction the spring 94 will urge the piston toward the shoulders 72 and 84, returning liquid to the chamber.

The form of the invention illustrated in Figure 7 is similar to that shown in Figure 6, but in this case the upper coupling member 10a does not have the sleeve-like portion 89 thereon, and the shoulder 72 defines one end of the annular compartment 86a between the upper manrel section 16 and the barrel 12. Within the compartment 3612 an annular piston 88a is movably positioned, and suitable sealing means 2a is provided on the piston to form a fluid-tight seal between the piston and the mandrel section 16 and between the piston and the barrel 12. A coil spring 94a is also disposed in the compartment 86a which yieldably urges the piston toward the shoulder 72. This form of the invention is other- 6 wise substantially the same as that illustrated in Figure 6, and operates in the same manner.

In Figure 8 there is illustrated a somewhat modified form of the invention similar to the form illustrated in Figure 5. In this case, however, the casing 74 is omitted and the flexible hollow container 76a is positioned within the compartment whose ends are defined by the lower end of the upper coupling member 10 and the shoulder 72 between the upper mandrel section 16 and the barrel 12. In other respects this form of the invention is similar to the form shown in Figure 5, and functions in the same manner.

A still further embodiment of the invention is illustrated in Figure 9, and in Figure 10 there is shown a somewhat modified form of the embodiment of Figure 9. As seen in Figure 9, the structure of the jar is substantially the same as that described in connection with Figure 7 except that the inwardly thickened portion b of the barrel i2 is of greater width than the portion 70 previously described, whereby a relatively wide upwardly facing annular shoulder 72!) is provided defining the open end of an annular compartment 861; in communication with the fluid chamber 43. In this form of the invention an O-ring 1% takes the place of the piston 88a, which O-ring is preferably of flexible material such as rubber, or the like. The operation of this form of the invention is similar to that already described, the O-ring 196 moving upwardly in the compartment 86b against the pressure of the air therein during the movement of the piston 58 in the restriction 5%, as the barrel 12 moves downwardly relative to the mandrel. Likewise, as soon as the piston 58 moves up out of the restriction the pressure of air in the compartment 86b returns the O-ring to a position in engagement with the shoulder 72b, thus returning the liquid from within the compartment to the fluid chamber 43.

The form of the invention illustrated in Figure 10 is like that shown in Figure 7, except that the portion 7% of the barrel is thickened as indicated at 70]) to provide the relatively wide upwardly facing shoulder 72]; with which the O-ring 1% is engageable at the limit of its outward movement in the compartment 86b. The O ring 106 in this case is provided with a back-up ring 1%, and there is a coil spring 94b within the compartment 36b which bears at one end upon the back-up ring and at the other end against the upper coupling member 10b. The spring 9412 urges the 0-ring toward the shoulder 725.

This form of the invention is in other respects similar to the form illustrated in Figure 6, and functions in a similar manner.

It will be apparent that the compressible means described may be provided at either side of the restriction in the chamber, whereby the tool may be adapted for jarring either upwardly or downwardly as may be desired.

It will also be apparent that the invention, as described above provides a jarring tool having a closed chamber which may be maintained filled with liquid, in order to secure the maximum efiiciency in the operation of the tool hydraulically, and wherein means is provided for compensating for variations in the volume of the chamher during the operation of the tool, so that injury or excessive wear of the packing elements is prevented, as well as leakage of the liquid from the chamber due to the development of excessive hydraulic pressures or the entrance of air into the chamber past the packing elements in the event of any increase in the volume of the chamber due to imperfection in the manufacture of the parts.

The invention has been disclosed in connection with certain specific embodiments of the same, but it will be understood that these are intended by way of illustration only, and that numerous changes can be made in the construction and arrangement of the various parts, without departing from theQspirit of the.-invention, or the scope ofi the appended claims...

Having thus clearly shown-and described the invention, what is claimed as new and desired to secure by Letters Patent isl; A'well tool comprising inner and outer concentrically arranged tubular parts movable longitudinally relative to. each other, means for connecting one of said parts to an operating string, meansfor connecting the other of said partsto an object stuck in a well bore, said parts forming an annular liquid containing chamber between the parts, a piston on the. inner part in the. chamber, sealing means between the parts at each end of said chamber, saidouter parthaving a portion of reduced internal diameter in the chamber. forming a restriction between the ends of the chamber in which said piston is adapted to move upon relative longitudinal movement of said inner and router parts, the external diameter of the piston being slightly smaller than the internal diameter of said restriction to permit the flow of liquid from one side of the piston to the other side thereof as the piston moves in said portion, pressure responsive means in said chamber on one side of said restriction, including a closed container of flexible material and compressible material filling said container, said means beingresponsive to variations in thepressure in said chamber on said one side of said restriction upon, relative longitudinal movement of said parts to permit movement of the piston in one direction in said restriction against a reduced restraining force.

2. A well tool comprising inner and outer concentrically arranged tubular parts movable longitudinally relative to each other, means for connecting one of said parts to an operating string, means for connecting the other of said parts to an object stuck in a well bore, said parts formingannular liquid filled chamber between the parts, a piston on the inner part in the chamber, sealing means between the parts at each end of said chamber, said outer part havinga portion of reduced internal diameter forming a restriction between the ends of the chamber in which said piston is adapted to move upon relative longitudinal movement of said inner and outer parts, the external diameter of the piston being slightly smaller than the internal diameter of said restriction to permit the flow of liquid fromone side of the piston to the other side thereof as the piston moves in said restriction, means.

connected with the outer part and forming an annular compartment between said inner and outer parts, said compartment being closed at one end and opening at its other end into said chamber, a compressible. fluidin said- V callyarranged tubular parts movable longitudinally relative to each other, means for connecting one of said parts. to an operating string, means for connecting the other of said parts to an object stuck in a well bore, said parts forming between them a liquid containing chamber,

a piston on the inner part in the chamber, sealing means a at each end of said chamber between said inner and outer parts, said outer part having a portion of reduced internal dimeter forming a restriction in the chamber in which the piston is adapted to move upon relative longitudinal movement of said inner and outer parts, the external diameter of the piston being slightly smaller than internal diameter. of said restriction to permit the flow of liquid from one side of the piston to the other side thereof as the piston; moves .in said restriction, a compressible fluid in said chamber 01170116 sideof said restriction, movable. means. in said chamber separating said fluid from the tion to effect compresion of said compressible fluid.

parts formingtbetween them a liquid containing chamber, a piston on the inner partin the chamber, sealing means at each end of said chamber between said inner and outer parts, said outer-part having a'portion of reduced internal diameter forming a restrictionin the chamber in which the piston is adapted to move upon relative longitudinal movement of said inner and outer, parts, the'external' diameter of the-piston being slightly smaller than the internal diameter of said restriction to permit the flow of liquidfrom. one side of the piston to the-other sidev thereof as the piston moves in said restriction, a compressible fluid in said chamber on. one side of saidrestriction, movable means in the chamber separating said' from the. liquid therein, said meansbeing movable in one direction upon an increase in pressure in said chamber on one side of said. restriction to compress said fluid,

and in another. direction upon a decrease of pressure in" said chamberon said one side of said restriction to permit said fluid to expand,

5. A- well tool comprising inner and outer concentrically arranged tubular parts. movable longitudinally. relative to each other, means for connecting one of said parts to an operating string, means for connecting the other of said parts to an object stuck in a well bore, said parts forming between them a liquid containing chamber, a piston on the innerpart in the'chamber, said piston having a duct leading from the'upper to the lower side thereof, sealing means at each end of said chamber between said parts, said outer part having a portion of reduced internal diameter forming a restriction between the ends of the chamber in which the piston is adapted to move upon relative longitudinal movement of said inner and outer parts, said piston being of a size to substantially close said restriction to cause a flow of liquid through said duct from one side of thepiston to the other side thereof as the piston moves in said restriction, a compressible fluidin said chamber onone side of said restriction, means in said chamber separating said fluid from the'liquid therein and movable in the chamber in response to changes in the pressure in said chamber on said one side of said.

7 piston on the. inner, part in the chamber, sealing means at each end of said chamber between said inner and outer parts, said outer part having a portion of reducedinternal diameterv forming a restriction between the ends of the chamber and in which the piston is adapted to move upon relative longitudinal movement of said inner and outer parts, the external diameter of the piston being slightly smaller than the internal diameter of said restriction to. permit the flowot liquidfrom one side of thepiston to the other side thereof as the piston moves in said restric-' tive to each. other,,means for connecting one, of said partsto an operating string, means for connecting the other of said parts to an object stuck in a well bore, said parts forming between them -a liquid containing chamber, a piston on the inner part in the chamber, sealing means at each end of said chamber between said inner and outer parts, said outer part having a portion of reduced internal diameter forming a restriction between ends of the chamber in which the piston is adapted to move upon relative longitudinal movement of said inner and outer parts, a compressible fluid in said chamber on one side of the restriction, movable means in said chamber separating said fluid from the liquid therein and movable in response to an increase of pressure in said chamber on said one side of said restriction to eifect compression of said compressible fluid.

References Cited in the file of this patent UNITED STATES PATENT-S 1,804,700 Maxwell "May 12, 1931 2,265,431 Kerr -d Dec. 9, 1941 2,364,869 Osmun Dec. 12, 1944 10 2,499,695 Storm Mar. 7, 1950

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1804700 *Apr 5, 1927May 12, 1931Maxwell William HJarring tool
US2265431 *Jan 11, 1939Dec 9, 1941Eldon Peek JHydraulic jar
US2364869 *Feb 13, 1942Dec 12, 1944Osmun Fred NJar
US2499695 *Mar 18, 1947Mar 7, 1950Storm Lynn WJar
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2802703 *Aug 2, 1956Aug 13, 1957Houston Engineers IncHydraulic jar
US2819876 *Apr 6, 1954Jan 14, 1958Ransom Russell ACombined safety joint and jar
US2891772 *Nov 30, 1953Jun 23, 1959S R Bowen CoOil well jar-sealed type
US2898084 *Dec 16, 1954Aug 4, 1959Jersey Prod Res CoSeismic shock source
US2972471 *Nov 8, 1956Feb 21, 1961Shaffer Tool WorksOil sealed drilling bumper sub
US2996131 *Jun 3, 1957Aug 15, 1961Greenwood Eugene CLubricant packed bumper sub
US3016961 *Aug 13, 1957Jan 16, 1962Texaco IncRadioactivity geophysical prospecting
US3062305 *Dec 22, 1959Nov 6, 1962Sutliff Wayne NHydraulic oil well tool
US3233690 *Sep 2, 1964Feb 8, 1966Lawrence Richard RFlexible well jar
US3349858 *Oct 14, 1965Oct 31, 1967Baker Oil Tools IncHydraulic jarring apparatus having a restricted flow path from its chamber with constant flow regulator means
US3382936 *May 28, 1966May 14, 1968Hughes Tool CoShock absorbing and static load supporting drill string apparatus
US3804185 *Aug 12, 1971Apr 16, 1974Mason Tools Ltd LeeJarring and bumping tool for use in oilfield drilling strings
US3853187 *Feb 7, 1974Dec 10, 1974Downen JDuplex hydraulic-mechanical jar tool
US3955634 *Jun 23, 1975May 11, 1976Bowen Tools, Inc.Hydraulic well jar
US4023630 *Jan 14, 1976May 17, 1977Smith International, Inc.Well jar having a time delay section
US4462471 *Oct 27, 1982Jul 31, 1984James HippBidirectional fluid operated vibratory jar
US4844183 *Oct 28, 1987Jul 4, 1989Dailey Petroleum Services, Corp.Accelerator for fishing jar with hydrostatic assist
US5906239 *Apr 11, 1997May 25, 1999Iri International CorporationJarring tool
US7753116Jun 6, 2008Jul 13, 2010David BudneyDouble-acting jar
USRE28768 *Dec 30, 1974Apr 13, 1976Lee-Mason Tools Ltd.Jarring and bumping tool for use in oilfield drilling strings
Classifications
U.S. Classification175/297
International ClassificationE21B31/00, E21B31/113
Cooperative ClassificationE21B31/113
European ClassificationE21B31/113