US2953352A - Tensile energy accumulator and shock absorbing device for well pipe strings - Google Patents

Tensile energy accumulator and shock absorbing device for well pipe strings Download PDF

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US2953352A
US2953352A US752987A US75298758A US2953352A US 2953352 A US2953352 A US 2953352A US 752987 A US752987 A US 752987A US 75298758 A US75298758 A US 75298758A US 2953352 A US2953352 A US 2953352A
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section
mandrel
chamber
plunger
piston
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Webb Derrel Dee
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Houston Engineers Inc
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Houston Engineers Inc
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B31/00—Fishing for or freeing objects in boreholes or wells
    • E21B31/107—Fishing for or freeing objects in boreholes or wells using impact means for releasing stuck parts, e.g. jars
    • E21B31/113—Fishing for or freeing objects in boreholes or wells using impact means for releasing stuck parts, e.g. jars hydraulically-operated

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  • the jarring tool is normally interposed in the pipe string relatively close to the drilling tools and in operation when it is desired to remove partsY which khave become jammed in the well bore, a strong upward force is applied to the pipe string and thereafter the jarring tool is actuated to impart hammer blows tothe same in order to free the stuck parts and permit withdrawalof the same from the well bore.
  • the operation of the jarring tool imparts extremely high impact loads or shock to the well string, as well as to the jammed tool or other part wedged in the well and also tothe hoisting equipmentrat the surface. Such shock materially reduces the life of the well equipment and also reduces the effectiveness of the jarring operation.
  • a further object of the invention is the provision of a tensile energy accumulator and shock absorbing device for well pipe strings which operates to store tensile energy and release the same on the actuation of a jarring tool and at the same time, operates to absorb shock caused by operation of such jarring tool.
  • a still further object of the invention is the provision of a tensile energy accumulator and' shock absorbing device for well pipe strings which may be installed in the string adjacent a jarring tool Yand in which relative movement caused by operation of the jarring tool isl substantially confined to the section between theupper end of the energy'accumulator and shock absorbing device and the tool or other' object to be removed from the well, thereby maintaining the eliiciency of the jarring device and preventing absorption of the force exerted therebyV by the pipe string disposed in a well having a crooked bore or one drilled at an angle to the vertical.
  • Another object of the invention is the provision of a tensile energy accumulator and shock absorbing device for well pipe strings which may be conveniently installed in such pipe string and which will in no way interfere with normal drilling operations.
  • a further object ofthe invention is the provision of a tensile energy accumulator and shockk absorbing device for well pipe strings utilizing a compressible non-combustible uid for accumulating and storing tensile energy and also incorporating a valve controlled means for facilitating introduction of such compressible uid into the device.
  • a stillr further object of the invention is the provision of a tensile energy accumulator and shock absorbing device for well pipe strings which may be conveniently and economically manufactured from readily available materials and which may be conveniently utilized with conventional jarring tools and other well equipment.
  • Fig la is a longitudinal sectional view of the upper half of a tensile energy accumulator and shock absorbing device'constructed in accordance with this invention.
  • Fig. 1b a longitudinal sectional view showing the lower half of the tool shownin Fig. la;
  • Fig. 2 ⁇ a sectional view taken substantially on the line 2,:-2 of Fig. la;
  • Fig. 3 a fragmentary sectional Iview showing the means for facilitating 'introduction of compressible fluid into the toolfof this invention.
  • a tensile energyaccumul'ator'and shock absorbing device constructed in accordance with' this invention and which may. wellcomprise an elongated'v tubular body 10 having 1arniupper section 11,y a central section 12 and a lower sectionl',V Y
  • the upper section 11 is provided with a collar 14 threadedly received' in the upper end thereof and the collar 14 serves to ⁇ provide a downwardly facing abutment 15 within the upper section 11.
  • the collar v14 is provided with splines 1'6 which' inter-engage with splines l1,7 on a hollow mandrel 18 which is slidably received in the collar 14 and upper section 11 ⁇ .
  • the mandrel 18 is provided at the fupper end with conventional screw threaded means l9 ⁇ for facilitating connecting the same to a wellv pipe string and the mandrel 18 is provided with a fluid passage 20 extending therethrough.
  • the splines 116. and 17 serve to Vprevent relative rotation between the mandrel 18 andthe body 10, but permit sliding movement ofthe mandrel 18 within the collar 14 and upper section 11.
  • a coupling member 21 is secured to the lower end of the mandrel 18 by screw threaded or other suitable fasteningmeans 22 and the coupling member 21 serves to provide an upwardly facing shoulder 23 and a downwardly facing shoulder 24. Vent openings 25 and 26 are provided in the upper and lower ends respectively of the upper section 11 and serve to release any uid whichmay collect therein which might otherwise impede vertical movement of the mandrel 18 within the upper section 11.
  • a coupling section 27 serves to connect theupper section 11 andthecentral section 12 and the coupling section 27 maybe secured' to the' upper section 11 by screw threaded' or otherisuitableffastening means 28l and this coupling'section 27 serves-to' provide an upwardly facingabutment 29 in the lower end of the upper section 11.
  • the abutments and 29 serve to limit axial vertical movement of the mandrel 18 within the upper section 11, the upper limit of movement being reached when the shoulder 23 engages the abutment 15 andthe lower limit of movement being reached when the shoulder 24 engages the abutment 29 on the coupling section 27.
  • the coupling section 27 is connected to the central Section 12 by screw threaded or other suitable fastening means 30 and if desired, suitable packing means 31 may be provided in the joint between the coupling section 27 and the central section 12 in order to prevent leakage of uid through this joint.
  • a hollow plunger 32 is connected to the coupling member 21 by screw threaded or other suitable fastening means 33 and the plunger 32 extends through the coupling section 27 and the central section 12 and terminates at its lower end 34 within the lower section 13.
  • the plunger 32 is provided with a passage 35 extending therethrough in axial alignment with the passage in the mandrel 18.
  • An elongated cylindrical chamber -36 is provided in the central section 12 and a piston 37 on the plunger 32 is provided with packing means 38 for providing a uid tight engagement between the piston 37 and the wall of the chamber 36.
  • the upper portion of the central section 12 is provided with a transverse bore 39 extending to the exterior thereof and in alignment with the bore 39 is a threaded counterbore 40 for receiving a valve plug 41 which may be manipulated to open or close the bore 39.
  • Communicating with the counterbore 40 outwardly of the valve seat 42 is a threaded bore 43 normally closed by a threaded plug 44 but upon removal of the plug 44, a source of compressible non-combustible lluid may be connected to the threaded bore 43 and upon opening of the valve plug 41, such fluid may be forced into the chamber 36 to fill the same with uid above the piston 37 at any desired pressure. Closure of the valve plug 41 against the seat 42 will permit removal of the source of uid and insertion of the closure plug 43 without the loss of fluid from the chamber 36.
  • Fluid tight packing means 45 is provided in the coupling section 27 engaging the plunger 32 to prevent leakage of uid from the chamber 36 to the interior of the upper section-11 and a fluid tight packing means 46 is provided in the upper portion of the lower section 13 engaging the plunger 32 to prevent leakage of fluid ⁇ from the chamber 36 into the lower section 13.
  • the lower section 13 is provided with conventional screw threaded means 47 for detachably connecting the lower section 13 to a jarring tool or other equipment disposed in the well above the jarring tool.
  • the tensile energy accumulator and shock absorbing device of this invention is installed in a well pipe string with the mandrel 18 connected to the lower end of the well pipe string by means of the threaded connection 19 and with the lower section 13 of the device connected by means of the connection 47 to a jarring tool or other equipment in the well above the jarring tool.
  • the chamber 36 is filled with a compressible noncombustible fluid to the desired pressure and during normal drilling operations, the piston 37 on the plunger 32 will be located adjacent the lower end of the chamber 36 as clearly shown in Fig. lb.
  • Actuation of the jarring tool will serve to impart a sudden impact or hammer blow to the equipment below the device of this invention which will result in movement of the body 10 upwardly with relation to the plunger 32 and mandrel 18 and during such upward movement, the energy stored in the compressed fluid in the chamber 36 will be expended to maintain an upward ⁇ force on the jarring tool and other equipment in the well below the device of this invention and this relative movement between the body 1% and they plunger 32 and mandrel 18 will serve to absorb the shock to the pipe string and equipment above the device of this invention which would normally be caused by actuation of the jarring tool. This operation may be repeated as many times as necessary to free the stuck equipment.
  • a device which serves as a cushion between a jarring tool and a well pipe string and hoisting equipment, as well as a device for storing tensile energy which may be expended upon actuation of the jarring tool to maintain the eciency of such jarring tool, regardless of the freedom of movement of the equipment above such tool, which movement might be impeded by a crooked well bore or one drilled at an angle from the vertical and furthermore such device will operate to absorb the shock resulting from actuation of the jarring tool.
  • the device of this invention may be utilized with conventional jarring tools and other well equipment without necessitating modification thereof and will also operate to materially increase the life and maintain the eiciency of such equipment.
  • a tensile energy accumulator and shock absorbing device for well pipe strings comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, a collar threadedly received in the upper end of said upper section surrounding said mandrel and providing a downwardly facing abutment within said upper section, inter-engaging splines on said collar and mandrel to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel within said upper section and providing upwardly and downwardly facing shoulders, a coupling section between said upper section and said central section and providing an upwardly facing abutment in said upper section, engagement of said-shoulders with said abutments serving to limit axial movement of said mandrel in said upper section,
  • a device as defined in claim 1 in which said upper section is provided with vent apertures adjacent the upper and lower ends thereof to permit release of fluid within said upper section.
  • a tensile energy accumulator and shock -absorbing device for well pipe strings comprising an elongated tubular body having an upper sect-ion, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said vmandrel for detachably connecting a well pipe string, a collar threadedly received in the upper end of said upper section surrounding said mandrel and providing a downwardly facing abutment within said upper section, inter-engaging splines on said collar and mandrel to lprevent relative rotation between said mandrelv and body, a coupling member secured to the lower end of said mandrel within said upper section and providing upwardly and downwardly facing shoulders, a coupling section between said upper section and said central section and providing an upwardly facing abutment in said upper section, engagement of said shoulders with said abutments serving to limit axial movement of said mandrel
  • a tensile energy accumulator and shock absorbing device for well pipe strings comprising an elongated tubular body having an upper section, a central'section andl a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, a collar secured in the upper end of said upper section surrounding said mandrel and providing a downwardly ⁇ facing abutment within said upper section, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel within said upper section and providing upwardly and downwardly facing shoulders, a coupling section Vbetween said upper section and said central section and providing an upwardly facing abutment in said upper section, engagement of said shoulders with said abutments serving to limit axial movement of said mandrel in said upper section, a hollow plunger connected to said coupling member extending through said coupling section and said
  • a tensile energy accumulator and shock absorbing device for well pipe strings comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, a collar secured ini the upper end of said upper section surrounding said mandrel and providing a downwardly facing abutment within said upper section, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel within said upper section and providing upwardly and downwardly facing shoulders, a coupling section bet-Ween said upper section and said central section and providing an upwardly facing abutment in said upper section, engagement of said shoulders with said abutment serving to limit axial movement of said mandrel.
  • ay hollow plunger connected to said coupling member extending throughy said coupling section and said central section and into said lower section,:an elongated cylindrical chamber in said central section, a piston on said plunger having a iiuid tight sliding engagement with ythe wall of said chamber, means ⁇ in the upper portion of said central section for facilitating the introduction of a compressible uid intousaid chamber above said piston, fluid tight packing means in saidcoupling.
  • a tensile energy accumulator and shock absorbing device for wellV pipe strings comprising kan elongated tubular body havingfan upper section, a centralrsectionand ⁇ alower section, said sections being detachably secured together, a hollow mandrel slidably received insaid upper section, means on the upper 'end of said mandrel for detachably connecting arwell pipe string, means to prevent relative rotatonbetween said mandrel and body, a couplingmember secured to the lower end of said mandrel within said upper section, a coupling section betweenfsaid upper section and said central section, means to limit axial movement of said mandrel in said upper section, ak hollow plunger connected to said coupling member extending through said coupling section and said central section and into said lower section, an elongated cylindrical chamber in said central section, a piston onv said plunger having a fluid tight sliding engagement-with the wall of said chamber, means inthe upper portion of said central section for facilitating the introduction of
  • a tensile energy accumulator and shock absorbing device for well pipe strings comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel within said upper section, means to limit axial movement of said mandrel in said upper section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and into said lower section, an elongated cylindrical chamber in said central section, a piston on said plunger having ra fluid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible fluid into said chamber above said piston, iiuid tight packing means in said coupling section engaging said plunger to prevent leakage of fluid from
  • a tensile energy accumulator and shock absorbing device for well pipe strings comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel, a coupling section between said upper section and said central section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and into said lower section, an elongated cylindrical chamber inV said central section, a piston on said plunger having a tuid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible fluid into said chamber above said piston, uid tight packing means in said coupling section engaging said plunger to prevent leakage of fluid from said chamber to said upper
  • a tensile energy accumulator and shock absorbing device for well pipe strings comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, Imeans on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between saidmandrel and ⁇ said body, a coupling member secured to the lower end of said mandrel, a coupling section between said upper section and said central section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and into said lower section, an elongated cylindrical chamber in said central section, a piston on said plunger having a iiuid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible uid into said chamber above said piston, means -to prevent leakage of iluid from said chamber to said upper section
  • a tensile energy accumulator and shock absorbing device for well pipe strings comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel, a hollow plunger connected to said coupling member extending through said central section and into said lower section, an elongated cylindrical chamber in said central section, a piston on said plunger having a iiuid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible fluid into said chamber above said piston, means to prevent leakage of iluid from said chamber to said upper section, means to prevent leakage of fluid from said chamber lto said lower section and means on the lower end of said lower section
  • a tensile energy accumulator and shock absorbing device for well pipe strings comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower find, 0f Said mandrel, a hollow plunger connected to said coupling member extending through said central section and into said lower section, an elongated cylindrical chamber in sa-id central section, a piston on said plunger having a uid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible fluid into said chamber labove said piston and means on the lower end of said lower section for detachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel

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Description

Sept. 20, 1960 D. D. WEBB 2,953,352
TENSILE ENERGY AccuMuLAToR AND sHocK ABsoRBING DEVICE Foa WELL PIPE STRINGS f Filed Aug. 4, 195e INVENTOR @4f/eea .0. Wf
a. A A
ATTORNEY Patented Sept. 20, 1960 United States PatentOfiice TENSILE ENERGY ACCUMULTOR AND lSHOCK ABSORBING DEVICE FOR WELL PIPE STRINGS Derrel Dee Webb, Houston, Tex., assigner to Houston Engineers, Inc., Houston, Tex., a corporation of Texas Filed Aug. 4, 1958, Ser. No. 752,987
11 Claims. (Cl. Z55- 28) go. to a great depth in the earth, the drilling tools are attached to the lower end of a pipe string which is loweredrwithin the well and provides the driving connection for the `drilling tools.V Occasionally, either the tools or the pipe become jammed4 or wedged in the well and it is sometimes exceedingly diflicult to remove such parts from the well in order to repair the Ysame and resume drilling operations. Where a direct pullV from the surface is insuilicient to dislodge the stuck parts, it has been cus'- tornary to utilize what. is commonly known as a jarring tool. which in eliectyprovides a succession of hammer blows in an axial direction to free the parts and permit withdrawal of the same from the Well. o
The jarring tool is normally interposed in the pipe string relatively close to the drilling tools and in operation when it is desired to remove partsY which khave become jammed in the well bore, a strong upward force is applied to the pipe string and thereafter the jarring tool is actuated to impart hammer blows tothe same in order to free the stuck parts and permit withdrawalof the same from the well bore. The operation of the jarring tool imparts extremely high impact loads or shock to the well string, as well as to the jammed tool or other part wedged in the well and also tothe hoisting equipmentrat the surface. Such shock materially reduces the life of the well equipment and also reduces the effectiveness of the jarring operation. It has also been found that the effectiveness of conventional jarring tools is materially reduced when such tools are utilized in a well bore which is crooked or has been drilled at an angle to the vertical, since the jarring effect is absorbed in the pipe string and is not applied in its full intensity to the object to be removed. s
It is accordingly an object of the invention to provide a tensile energy accumulator and shock absorbing device which may be conveniently installed in well pipe strings without requiring any modification whatsoever, and which operates to materially increase the eciency of jarring tools also installed in the pipe string.
A further object of the invention is the provision of a tensile energy accumulator and shock absorbing device for well pipe strings which operates to store tensile energy and release the same on the actuation of a jarring tool and at the same time, operates to absorb shock caused by operation of such jarring tool.
A still further object of the invention is the provision of a tensile energy accumulator and' shock absorbing device for well pipe strings which may be installed in the string adjacent a jarring tool Yand in which relative movement caused by operation of the jarring tool isl substantially confined to the section between theupper end of the energy'accumulator and shock absorbing device and the tool or other' object to be removed from the well, thereby maintaining the eliiciency of the jarring device and preventing absorption of the force exerted therebyV by the pipe string disposed in a well having a crooked bore or one drilled at an angle to the vertical.
Another object of the invention is the provision of a tensile energy accumulator and shock absorbing device for well pipe strings which may be conveniently installed in such pipe string and which will in no way interfere with normal drilling operations.
A further object ofthe invention is the provision of a tensile energy accumulator and shockk absorbing device for well pipe strings utilizing a compressible non-combustible uid for accumulating and storing tensile energy and also incorporating a valve controlled means for facilitating introduction of such compressible uid into the device. s
A stillr further object of the invention is the provision of a tensile energy accumulator and shock absorbing device for well pipe strings which may be conveniently and economically manufactured from readily available materials and which may be conveniently utilized with conventional jarring tools and other well equipment.
`Further objects and advantages of the invention will be apparent from the following description taken in conjunction with the accompanying drawing wherein:
"Fig la is a longitudinal sectional view of the upper half of a tensile energy accumulator and shock absorbing device'constructed in accordance with this invention;
Fig. 1b a longitudinal sectional view showing the lower half of the tool shownin Fig. la;
Fig. 2 `a sectional view taken substantially on the line 2,:-2 of Fig. la; and
Fig. 3 a fragmentary sectional Iview showing the means for facilitating 'introduction of compressible fluid into the toolfof this invention.
` With continued reference' to the drawing, there is shown a tensile energyaccumul'ator'and shock absorbing device constructed in accordance with' this invention and which may. wellcomprise an elongated'v tubular body 10 having 1arniupper section 11,y a central section 12 and a lower sectionl',V Y The upper section 11 is provided with a collar 14 threadedly received' in the upper end thereof and the collar 14 serves to` provide a downwardly facing abutment 15 within the upper section 11. The collar v14 is provided with splines 1'6 which' inter-engage with splines l1,7 on a hollow mandrel 18 which is slidably received in the collar 14 and upper section 11`. The mandrel 18 is provided at the fupper end with conventional screw threaded means l9`for facilitating connecting the same to a wellv pipe string and the mandrel 18 is provided with a fluid passage 20 extending therethrough. The splines 116. and 17 serve to Vprevent relative rotation between the mandrel 18 andthe body 10, but permit sliding movement ofthe mandrel 18 within the collar 14 and upper section 11. A coupling member 21 is secured to the lower end of the mandrel 18 by screw threaded or other suitable fasteningmeans 22 and the coupling member 21 serves to provide an upwardly facing shoulder 23 and a downwardly facing shoulder 24. Vent openings 25 and 26 are provided in the upper and lower ends respectively of the upper section 11 and serve to release any uid whichmay collect therein which might otherwise impede vertical movement of the mandrel 18 within the upper section 11. g
A coupling section 27 serves to connect theupper section 11 andthecentral section 12 and the coupling section 27 maybe secured' to the' upper section 11 by screw threaded' or otherisuitableffastening means 28l and this coupling'section 27 serves-to' provide an upwardly facingabutment 29 in the lower end of the upper section 11. The abutments and 29 serve to limit axial vertical movement of the mandrel 18 within the upper section 11, the upper limit of movement being reached when the shoulder 23 engages the abutment 15 andthe lower limit of movement being reached when the shoulder 24 engages the abutment 29 on the coupling section 27. The coupling section 27 is connected to the central Section 12 by screw threaded or other suitable fastening means 30 and if desired, suitable packing means 31 may be provided in the joint between the coupling section 27 and the central section 12 in order to prevent leakage of uid through this joint.
A hollow plunger 32 is connected to the coupling member 21 by screw threaded or other suitable fastening means 33 and the plunger 32 extends through the coupling section 27 and the central section 12 and terminates at its lower end 34 within the lower section 13. The plunger 32 is provided with a passage 35 extending therethrough in axial alignment with the passage in the mandrel 18.
An elongated cylindrical chamber -36 is provided in the central section 12 and a piston 37 on the plunger 32 is provided with packing means 38 for providing a uid tight engagement between the piston 37 and the wall of the chamber 36.
As best shown in Fig. 3, the upper portion of the central section 12 is provided with a transverse bore 39 extending to the exterior thereof and in alignment with the bore 39 is a threaded counterbore 40 for receiving a valve plug 41 which may be manipulated to open or close the bore 39. Communicating with the counterbore 40 outwardly of the valve seat 42 is a threaded bore 43 normally closed by a threaded plug 44 but upon removal of the plug 44, a source of compressible non-combustible lluid may be connected to the threaded bore 43 and upon opening of the valve plug 41, such fluid may be forced into the chamber 36 to fill the same with uid above the piston 37 at any desired pressure. Closure of the valve plug 41 against the seat 42 will permit removal of the source of uid and insertion of the closure plug 43 without the loss of fluid from the chamber 36.
Fluid tight packing means 45 is provided in the coupling section 27 engaging the plunger 32 to prevent leakage of uid from the chamber 36 to the interior of the upper section-11 and a fluid tight packing means 46 is provided in the upper portion of the lower section 13 engaging the plunger 32 to prevent leakage of fluid `from the chamber 36 into the lower section 13. The lower section 13 is provided with conventional screw threaded means 47 for detachably connecting the lower section 13 to a jarring tool or other equipment disposed in the well above the jarring tool.
In operation, the tensile energy accumulator and shock absorbing device of this invention is installed in a well pipe string with the mandrel 18 connected to the lower end of the well pipe string by means of the threaded connection 19 and with the lower section 13 of the device connected by means of the connection 47 to a jarring tool or other equipment in the well above the jarring tool. The chamber 36 is filled with a compressible noncombustible fluid to the desired pressure and during normal drilling operations, the piston 37 on the plunger 32 will be located adjacent the lower end of the chamber 36 as clearly shown in Fig. lb.
Upon the drilling tool or other equipment below the device of this invention becoming wedged or stuck in the well, an upward force is exerted on the mandrel 18 by hoisting equipment at the surface and such upward force operates to move the mandrel 18 and plunger 32, as well as the piston 37 upwardly to compress the fluid in the upper portion of the chamber 36 until the upward pulling force is balanced by the pressure fluid in such chamber 36. This will also serve to exert an upward force on the jarring tool and equipment wedged in the well. Actuation of the jarring tool will serve to impart a sudden impact or hammer blow to the equipment below the device of this invention which will result in movement of the body 10 upwardly with relation to the plunger 32 and mandrel 18 and during such upward movement, the energy stored in the compressed fluid in the chamber 36 will be expended to maintain an upward `force on the jarring tool and other equipment in the well below the device of this invention and this relative movement between the body 1% and they plunger 32 and mandrel 18 will serve to absorb the shock to the pipe string and equipment above the device of this invention which would normally be caused by actuation of the jarring tool. This operation may be repeated as many times as necessary to free the stuck equipment.
it will be seen that by the above described invention, there has been provided a device which serves as a cushion between a jarring tool and a well pipe string and hoisting equipment, as well as a device for storing tensile energy which may be expended upon actuation of the jarring tool to maintain the eciency of such jarring tool, regardless of the freedom of movement of the equipment above such tool, which movement might be impeded by a crooked well bore or one drilled at an angle from the vertical and furthermore such device will operate to absorb the shock resulting from actuation of the jarring tool. The device of this invention may be utilized with conventional jarring tools and other well equipment without necessitating modification thereof and will also operate to materially increase the life and maintain the eiciency of such equipment.
It will be obvious to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the invention is not limited by that which is shown in the drawing and described in the specification, but only as indicated in the appended claims. What is claimed is:
l. A tensile energy accumulator and shock absorbing device for well pipe strings, said-device comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, a collar threadedly received in the upper end of said upper section surrounding said mandrel and providing a downwardly facing abutment within said upper section, inter-engaging splines on said collar and mandrel to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel within said upper section and providing upwardly and downwardly facing shoulders, a coupling section between said upper section and said central section and providing an upwardly facing abutment in said upper section, engagement of said-shoulders with said abutments serving to limit axial movement of said mandrel in said upper section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and terminating within said lower section, an elongated cylindrical chamber in said central section, a piston on saidplunger having a fluid tight sliding engagement with the wall of said chamber, coupling and valve means in the upper portion of said central section for facilitating the introduction of a compressible fluid into said chamber above said piston, fluid tight packing means in said coupling section engaging said plunger to prevent leakage of fluid from said chamber to said upper section,uid tight packing means in the upper portion of said lower section engaging said plunger to prevent leakage of fluid from said chamber to said lower section and meanson the lower end of said lower section for detachably connecting a jarring tool, whereby uponexerting an upward force on said mandrel said plunger and piston will move upwardly to compress einem y fluid in said chamber and impose an upward force on said jarringl tool and upon actuation of said jarringrtoolsaid body will `move upwardly relative to said plunger and piston to expend the energy stored in the compressed fluid and absorb shock caused by said jarring tool.
2. A device as defined in claim 1 in which said upper section is provided with vent apertures adjacent the upper and lower ends thereof to permit release of fluid within said upper section.
3. A tensile energy accumulator and shock -absorbing device for well pipe strings, said device comprising an elongated tubular body having an upper sect-ion, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said vmandrel for detachably connecting a well pipe string, a collar threadedly received in the upper end of said upper section surrounding said mandrel and providing a downwardly facing abutment within said upper section, inter-engaging splines on said collar and mandrel to lprevent relative rotation between said mandrelv and body, a coupling member secured to the lower end of said mandrel within said upper section and providing upwardly and downwardly facing shoulders, a coupling section between said upper section and said central section and providing an upwardly facing abutment in said upper section, engagement of said shoulders with said abutments serving to limit axial movement of said mandrel in said upper section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and terminating within said lower section, an elongated cylindrical chamber in s-aid central section, a piston on said plunger having a fluid tight sliding engagement with the wall of said chamber, means in the upper portion of said central section for facilitating the introduction of a compressible tluid into said chamber above said piston, lluid tight packing means in said coupling section engaging said plunger toprevent leakage of fluid from said chamber togsaid upper section, fluid tight packing means in the upper portion of said lower section engaging said plunger to prevent leakage of Huid from said chamber to said lower section and means on the lower end of said lower section for detachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel said plunger and piston will move upwardly to compress fluid in said chamber and impose an upward force on said jarring tool and upon actuation of said jarring tool said body will move upwardly relative to said plunger andV piston to expend the energy stored in the compressed uid and -absorb shockv caused by said jarring tool.
4. A tensile energy accumulator and shock absorbing device for well pipe strings, said device comprising an elongated tubular body having an upper section, a central'section andl a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, a collar secured in the upper end of said upper section surrounding said mandrel and providing a downwardly `facing abutment within said upper section, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel within said upper section and providing upwardly and downwardly facing shoulders, a coupling section Vbetween said upper section and said central section and providing an upwardly facing abutment in said upper section, engagement of said shoulders with said abutments serving to limit axial movement of said mandrel in said upper section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and terminating within said lower section, an elongated cylindrical chamber in ysaid central section, a kpiston on said plunger having a I fluid tight sliding engagement with the wall of Vsaidchamber, means in the upperv portion of said vcentral section for facilitating the introduction of a compressible fluid into Vsaid chamber above said piston, fluid tight packing means in said coupling section engaging said plunger to prevent leakage of uid from said chamber to saidr upper section, fluid tight packing means inthe upper portion of said lower section engaging said plunger to prevent leakage of uid from said chamber to said lower section and means on the lower end of said lower section for detachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel said plunger and piston will move upwardly to compress fluid in said chamber and impose an upward force on said jarring tool and upon actuation of said jarring tool said body will move upwardly relative'to said plunger and .piston to` expend the energy stored in the compressed'uid and absorb shock caused by said jarring tool.
- 5. A tensile energy accumulator and shock absorbing device for well pipe strings, said device comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, a collar secured ini the upper end of said upper section surrounding said mandrel and providing a downwardly facing abutment within said upper section, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel within said upper section and providing upwardly and downwardly facing shoulders, a coupling section bet-Ween said upper section and said central section and providing an upwardly facing abutment in said upper section, engagement of said shoulders with said abutment serving to limit axial movement of said mandrel. in said uppersection, ay hollow plunger connected to said coupling member extending throughy said coupling section and said central section and into said lower section,:an elongated cylindrical chamber in said central section, a piston on said plunger having a iiuid tight sliding engagement with ythe wall of said chamber, means `in the upper portion of said central section for facilitating the introduction of a compressible uid intousaid chamber above said piston, fluid tight packing means in saidcoupling. section engaging said plunger to prevent'leakage of tluid from said chamber to said upper section, tiuidtight packing means in the upper rportion of said lower section engaging said plunger to prevent leakage of tluid from said chamber to said lower section and means Aon the lower end of said lower section for detachably connect- .ing va jarringftool, whereby upon exerting an upward force on said mandrel said plunger and piston will move upwardly to compress fluid in said chamber and impose an .upward force on said jarring tool and upon actuation of said jarring tool said body will move upwardly relative to said plunger and piston to expend the energy stored in the compressed fluid and absorb shock caused` by said jarring tool.
6. A tensile energy accumulator and shock absorbing device for wellV pipe strings, saidf device comprising kan elongated tubular body havingfan upper section, a centralrsectionand` alower section, said sections being detachably secured together, a hollow mandrel slidably received insaid upper section, means on the upper 'end of said mandrel for detachably connecting arwell pipe string, means to prevent relative rotatonbetween said mandrel and body, a couplingmember secured to the lower end of said mandrel within said upper section, a coupling section betweenfsaid upper section and said central section, means to limit axial movement of said mandrel in said upper section, ak hollow plunger connected to said coupling member extending through said coupling section and said central section and into said lower section, an elongated cylindrical chamber in said central section, a piston onv said plunger having a fluid tight sliding engagement-with the wall of said chamber, means inthe upper portion of said central section for facilitating the introduction of a compressible fluid into said chamber above said piston, fluid tight packing means in said coupling section engaging said plunger to prevent leakage of fluid from said chamber to said upper section, fluid tight packing means in the upper portion of said lower section engaging said plunger to prevent leakage of fluid from said chamber to said lower section and means on the lower end of said lower section for detachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel said plunger and piston will move upwardly to compress uid in said chamber and impose an upward force on said jarring tool and upon actuation of said jarring tool said body will move upwardly relative to said plunger and piston to expend the energy stored in the compressed fluid and absorb shock caused by said jarring tool.
7. A tensile energy accumulator and shock absorbing device for well pipe strings, said device comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel within said upper section, means to limit axial movement of said mandrel in said upper section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and into said lower section, an elongated cylindrical chamber in said central section, a piston on said plunger having ra fluid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible fluid into said chamber above said piston, iiuid tight packing means in said coupling section engaging said plunger to prevent leakage of fluid from said chamber to said upper section, fluid tight packing means in the upper portion of said lower section engaging said plunger to prevent leakage of fluid [from said chamber to said lower section and means on the lower end of said lower section for de tachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel said plunger and piston will move upwardly to compress fluid in said chamber and impose an upward force on said jarring tool and upon actuation of said jarring tool said body will move upwardly relative to said plunger and piston to expend the energy stored in the compressed fluid and absorb shock caused by said jarring tool.
8. A tensile energy accumulator and shock absorbing device for well pipe strings, said device comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel, a coupling section between said upper section and said central section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and into said lower section, an elongated cylindrical chamber inV said central section, a piston on said plunger having a tuid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible fluid into said chamber above said piston, uid tight packing means in said coupling section engaging said plunger to prevent leakage of fluid from said chamber to said upper section, fluid tight packing means in the upper portion of said lower section engaging said plunger to prevent leakage of fluid from said chamber to said lower section and means on the lower end of said lower section :for detachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel said plunger and piston will move upwardly to compressV lluidV in said chamber and impose an upward force on said jarring tool and upon actuation of said jarring tool said body will move upwardly relative to said plunger and piston to expend the energy stored in the compressed 'uidrand absorb shock caused by said jarring tool.
9. A tensile energy accumulator and shock absorbing device for well pipe strings, said device comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, Imeans on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between saidmandrel and `said body, a coupling member secured to the lower end of said mandrel, a coupling section between said upper section and said central section, a hollow plunger connected to said coupling member extending through said coupling section and said central section and into said lower section, an elongated cylindrical chamber in said central section, a piston on said plunger having a iiuid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible uid into said chamber above said piston, means -to prevent leakage of iluid from said chamber to said upper section, means to prevent leakage of uid from said chamber to said lower section and means on the lower end of sa-id lower section for detachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel, said plunger and piston will move upwardly to compress iiuid in said chamber and impose an up ward force on said jarring tool and upon actuation of said jarring tool said body will move upwardly relative to said plunger and piston to expend the energy stored in the compressed fluid and Vabsorb shock caused by said jarring tool.
l0. A tensile energy accumulator and shock absorbing device for well pipe strings, said device comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower end of said mandrel, a hollow plunger connected to said coupling member extending through said central section and into said lower section, an elongated cylindrical chamber in said central section, a piston on said plunger having a iiuid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible fluid into said chamber above said piston, means to prevent leakage of iluid from said chamber to said upper section, means to prevent leakage of fluid from said chamber lto said lower section and means on the lower end of said lower section for detachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel said plunger and piston will move upwardly to compress fluid in said chamber and impose an upward force on said jarring tool and upon actuation of said jarring tool said body will move upwardly relative to said plunger and piston to expend the energy stored in the compressed iluid and absorb shock caused by said jarring tool.
ll. A tensile energy accumulator and shock absorbing device for well pipe strings, said device comprising an elongated tubular body having an upper section, a central section and a lower section, said sections being detachably secured together, a hollow mandrel slidably received in said upper section, means on the upper end of said mandrel for detachably connecting a well pipe string, means to prevent relative rotation between said mandrel and body, a coupling member secured to the lower find, 0f Said mandrel, a hollow plunger connected to said coupling member extending through said central section and into said lower section, an elongated cylindrical chamber in sa-id central section, a piston on said plunger having a uid tight sliding engagement with the wall of said chamber, means for facilitating the introduction of a compressible fluid into said chamber labove said piston and means on the lower end of said lower section for detachably connecting a jarring tool, whereby upon exerting an upward force on said mandrel said plunger and piston will move upwardly to compress Huid in said chamber and impose anupward force on said jarring References Cited in the le of this patent UNITED STATES PATENTS 1,804,700 Maxwell May 12, 1931 10 2,544,473 Smith Mar. 6, 1951 2,585,995 Brown Feb. 19, 1952
US752987A 1958-08-04 1958-08-04 Tensile energy accumulator and shock absorbing device for well pipe strings Expired - Lifetime US2953352A (en)

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3353613A (en) * 1965-09-24 1967-11-21 Houston Engineers Inc Fluid spring tensile energy accumulator and shock absorbing device for well pipe strings
FR2058260A1 (en) * 1969-08-14 1971-05-28 Sutliff Wayne
US4054040A (en) * 1974-02-21 1977-10-18 A-Z International Tool Company Telescoping torque transmission apparatus
US4387885A (en) * 1980-03-17 1983-06-14 Bowen Tools, Inc. Shock absorber assembly for absorbing shocks encountered by a drill string
US4422823A (en) * 1977-11-29 1983-12-27 Ioannesian Rolen A Turbodrill
US4844183A (en) * 1987-10-28 1989-07-04 Dailey Petroleum Services, Corp. Accelerator for fishing jar with hydrostatic assist
US4846273A (en) * 1987-09-21 1989-07-11 Anderson Edwin A Jar mechanism accelerator
US4963078A (en) * 1988-05-26 1990-10-16 Agee John O Stress and torque reducing tool and method
US20030034079A1 (en) * 2001-06-25 2003-02-20 Lee Arley Gene Pulsation dampener apparatus and method
US20040108144A1 (en) * 2001-03-03 2004-06-10 Gerhard Volkel Drilling device comprising a rotational drive
US20050023739A1 (en) * 2003-07-30 2005-02-03 Ford Michael Brent Shock absorbing and shock force generating apparatus and method for an oil pump
US20070137895A1 (en) * 2005-12-21 2007-06-21 Smith International, Inc. Percussion drill bit with V-shaped splines
US8505653B2 (en) 2010-04-01 2013-08-13 Lee Oilfield Service Ltd. Downhole apparatus
US8937521B2 (en) 2012-12-10 2015-01-20 Correlated Magnetics Research, Llc. System for concentrating magnetic flux of a multi-pole magnetic structure

Citations (3)

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Publication number Priority date Publication date Assignee Title
US1804700A (en) * 1927-04-05 1931-05-12 William H Maxwell Jarring tool
US2544473A (en) * 1946-05-24 1951-03-06 Lester W Smith Hydrostatic rotary jar
US2585995A (en) * 1947-03-21 1952-02-19 Cicero C Brown Drilling joint

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1804700A (en) * 1927-04-05 1931-05-12 William H Maxwell Jarring tool
US2544473A (en) * 1946-05-24 1951-03-06 Lester W Smith Hydrostatic rotary jar
US2585995A (en) * 1947-03-21 1952-02-19 Cicero C Brown Drilling joint

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3353613A (en) * 1965-09-24 1967-11-21 Houston Engineers Inc Fluid spring tensile energy accumulator and shock absorbing device for well pipe strings
FR2058260A1 (en) * 1969-08-14 1971-05-28 Sutliff Wayne
US4054040A (en) * 1974-02-21 1977-10-18 A-Z International Tool Company Telescoping torque transmission apparatus
US4422823A (en) * 1977-11-29 1983-12-27 Ioannesian Rolen A Turbodrill
US4387885A (en) * 1980-03-17 1983-06-14 Bowen Tools, Inc. Shock absorber assembly for absorbing shocks encountered by a drill string
US4846273A (en) * 1987-09-21 1989-07-11 Anderson Edwin A Jar mechanism accelerator
US4844183A (en) * 1987-10-28 1989-07-04 Dailey Petroleum Services, Corp. Accelerator for fishing jar with hydrostatic assist
US4963078A (en) * 1988-05-26 1990-10-16 Agee John O Stress and torque reducing tool and method
US7182158B2 (en) * 2001-03-03 2007-02-27 Tracto-Technik Gmbh Drilling device comprising a rotational drive
US20040108144A1 (en) * 2001-03-03 2004-06-10 Gerhard Volkel Drilling device comprising a rotational drive
US20030034079A1 (en) * 2001-06-25 2003-02-20 Lee Arley Gene Pulsation dampener apparatus and method
US6874540B2 (en) * 2001-06-25 2005-04-05 Smith International, Inc. Pulsation dampener apparatus and method
US6905114B2 (en) * 2003-07-30 2005-06-14 Michael Brent Ford Shock absorbing and shock force generating apparatus with shear pin for an oil pump and method therefor
US20050023739A1 (en) * 2003-07-30 2005-02-03 Ford Michael Brent Shock absorbing and shock force generating apparatus and method for an oil pump
US20070137895A1 (en) * 2005-12-21 2007-06-21 Smith International, Inc. Percussion drill bit with V-shaped splines
US8505653B2 (en) 2010-04-01 2013-08-13 Lee Oilfield Service Ltd. Downhole apparatus
US8937521B2 (en) 2012-12-10 2015-01-20 Correlated Magnetics Research, Llc. System for concentrating magnetic flux of a multi-pole magnetic structure

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