Patent Publication Number: US-10767430-B2

Title: Opposing piston setting tool

Description:
RELATED APPLICATIONS 
     This application is a continuation application of U.S. Nonprovisional patent application Ser. No. 15/563,798 filed Oct. 2, 2017, which is a 371 of International Patent Application No. PCT/US2016/025732 filed Apr. 1, 2016 which claims priority to U.S. Provisional Application No. 62/142,083, filed Apr. 2, 2015. 
    
    
     BACKGROUND OF THE INVENTION 
     Bridge plugs are often introduced or carried into a subterranean oil or gas well on a conduit, such as wireline, electric line, continuous coiled tubing, threaded work string, or the like, for engagement at a pre-selected position within the well along another conduit having an inner smooth inner wall, such as casing. The bridge plug is typically expanded and set into position within the casing. The bridge plug effectively seals off one section of casing from another. Several different completion operations may commence after the bridge plug is set, including perforating and fracturing. Sometimes a series of plugs are set in an operation called “plug and perf” where several sections of casing are perforated sequentially. When the bridge plug is no longer needed the bridge plug is reamed, often through drilling, reestablishing fluid communication with the previously sealed off portion of casing. 
     Setting a bridge plug typically requires setting a “slip” mechanism that engages and locks the bridge plug with the casing, and energizing the packing element in the case of a bridge plug. This requires large forces, often in excess of 20,000 lbs. The activation or manipulation of some setting tools involves the activation of an energetic material such as an explosive pyrotechnic or black powder charge, sometimes called a “power charge” to provide the energy needed to deform a bridge plug. The energetic material may use a relatively slow burning chemical reaction to generate high pressure gases. One such setting tool is the Model E-4 Wireline Pressure Setting Tool of Baker International Corporation, sometimes referred to as the Baker Setting Tool. 
     The pressure from the power charge igniting is contained with the power charge chamber by the sealed firing head. The pressure builds in the chamber and causes a floating first piston to move down through the tool, compressing the oil reservoir through a small hole in a connector sub. 
     The oil is pressed through the small hole in the connector sub and against a second piston. The hydraulic force applied against the second piston causes the piston to move. The second piston is coupled to a setting sleeve by way of a piston rod and sleeve crosslink. The setting sleeve moves away axially from the setting tool and compresses the outside of a bridge plug. A mandrel located down the center of the tool stays stationary. The mandrel is connected to the bridge plug via a shear stud. After the bridge plug is set, the setting tool is pulled upwards in the borehole until sufficient force is generated to shear the shear stud, thus separating the setting tool from the bridge plug. 
     After the bridge plug is set, the explosive setting tool may remain pressurized and must be raised to the surface and depressurized. This typically entails bleeding pressure off the setting tool by piercing a rupture disk or releasing a valve. 
     SUMMARY OF EXAMPLES OF THE INVENTION 
     An example embodiment may include a setting tool apparatus having a substantially cylindrical body with a center axis. It may also have a first chamber, a first piston slidably disposed within the first chamber and a first piston face. It may include a mandrel extending normal from the first piston face in a first direction, and a second piston slidably disposed in the first chamber. The embodiment may have a second piston face and an axial through bore. The mandrel of the first piston may slidably engage the axial through bore of the second piston. The first piston face, the second piston face, and the cylindrical body may form a pressure chamber. 
     A variation of the described embodiment may include the second piston moving along the axis in a first direction. The cylindrical body may move along the axis in the first direction. The embodiment may further have a shear stud coupled to the end of the mandrel. The second piston is located between the first piston and the shear stud along the mandrel. The embodiment may further have an expandable plug coupled to the shear stud. The expandable plug may be a bridge plug. The embodiment may further have a vent. A fluid can enter the pressure chamber. A first oil reservoir may be formed by the first piston and the cylindrical body. A second oil reservoir is formed by the second piston and the cylindrical body. The fluid may be a gas resulting from a chemical reaction. The fluid may be a hydraulic fluid. 
     Another example embodiment may include a setting tool apparatus having a cylindrical body with a center axis, a first end, a second end, an inner surface, and an outer surface. The setting tool has a first piston located within the cylindrical body and axially aligned with the cylindrical body. The first piston has a first end and a second end. It also has a fluid passage connecting the first end to the second end. A cylindrical mandrel extends from the second end of the first piston and is axially aligned with the cylindrical body. A second piston is located within the cylindrical body and is axially aligned with the cylindrical body. The second piston has an axial bore throughout its length. The second piston has a first end and a second end. The first end of the second piston, the second end of the first piston, and the cylindrical body form a variable volume pressure chamber. 
     A variation of the described embodiment may further include a sub connected to the first end of the cylindrical body having at least one orifice placing a first portion of the inside of the cylindrical body in fluid communication with the outside of the cylindrical body. The embodiment may have a sub connected to the second end of the cylindrical body. The sub may have at least one orifice placing a second portion of the inside of the cylindrical body in fluid communication with the outside of the cylindrical body. The embodiment may further have a power charge located proximate to the cylindrical body. The gases generated by the power charge can enter the fluid passage of the first piston at the first end and exit at the end of the fluid passage at the second end. The gases generated would then enter the variable volume pressure chamber. A firing head is coupled to the power charge. The mandrel may be disposed within the axial bore of the second piston. It may further have a cylindrical sub coupled to the second end of the cylindrical body. The cylindrical sub limits the stroke of the second piston with respect to the cylindrical body. It may further have a cylindrical sub coupled to the first end of the cylinder body. The cylindrical sub limits the stroke of the second piston with respect to the cylindrical body. It may further have a setting sleeve coupled to the second piston. It may further have a connector sub coupled to the mandrel. It may further have a shear stud coupled to the connector sub. It may further have an expandable plug coupled to the shear stud. The first piston may stay stationary while the second piston and cylindrical body each move axially away from the first piston. The fluid passage may provide fluid communication for a gas between the first end of the first piston and the variable volume pressure chamber. 
     Another example embodiment may include a method for setting a plug in a borehole. The method step may include activating a firing head, starting a gas pressure generating chemical reaction, pressurizing a chamber located with a cylinder with the generated gas pressure, moving a piston disposed within the cylinder in a first axial direction with the generated gas, and moving the cylinder in the first axial direction with the generated gas. 
     A variation of the example may further include placing a setting tool in a borehole at a predetermined location for installing a bridge plug. It may further include evacuating a first quantity of oil from the setting tool by moving the piston in the first axial direction. It may further include evacuating a second quantity of oil from the setting tool by moving the cylinder in the first axial direction. It may further include expanding a seal radially against an inner wall of a borehole casing. It may further include shearing a shear stud coupled between a setting tool and a setting plug. It may further include removing the setting tool from the borehole after setting a bridge plug. The radially expanded seal may be a bridge plug. 
     Another example embodiment may include a setting tool having a charge chamber and a cylindrical body having a top end and a bottom end. The setting tool may have a longitudinal axis extending through its center from the top end to the bottom end. It may have a top piston with a top end and a bottom end corresponding with the top end and bottom end of the pressure vessel. The top piston may provide a slidable seal within the pressure chamber cylinder. The setting tool may have a bottom piston with a top end and a bottom end corresponding with the top end and bottom end of the pressure vessel. The bottom piston may provide a slidable seal within the pressure chamber cylinder. A top piston mandrel connects the charge chamber to the top end of the top piston through the top end of the cylindrical body. A gas passage through the top piston mandrel provides fluid communication from the energetic material chamber to the pressure chamber cylinder between the top and bottom piston. A bottom piston mandrel connects the bottom piston to a setting sleeve. A setting mandrel extends from the bottom end of the top piston through the bottom piston and bottom piston mandrel. The top piston, bottom piston, and cylindrical body form a pressure chamber. 
     A variation of the example may further have a top fluid reservoir formed between the top end of the top piston and the top end of the cylindrical body. It may further have a bottom fluid reservoir formed between the bottom end of the bottom piston and the top end of the cylindrical body. It may further have a top orifice proximate to the top end of the cylindrical body. The top orifice is adapted to release fluid from the top fluid reservoir under pressure. It may further have a bottom orifice proximate the bottom end of the cylindrical body. The bottom orifice is adapted to release fluid from the bottom fluid reservoir under pressure. It may further have a bottom sub proximate the bottom end of the cylindrical body adapted to stop the bottom piston from exiting the bottom end of the cylindrical body. It also has a top sub proximate the top end of the cylindrical body adapted to stop the top piston from exiting the top of the cylindrical body. The charge chamber, pressure chamber cylinder, top piston, and bottom piston may all be coaxially aligned. The top piston mandrel, bottom piston mandrel, setting sleeve, and setting mandrel may all be coaxially aligned. It may further have an energetic charge disposed within the charge chamber. The combustion of the energetic charge creates gas that flows through the gas passage to the pressure chamber. The pressure created by the gas moves the bottom piston toward the bottom sub and further moves the top end of the cylindrical body down toward the top piston. The bottom piston may move toward the bottom sub to pressurize fluid in the bottom fluid reservoir and move it through the bottom orifice. The top end of the cylindrical body may move toward the top piston to pressurize fluid in the top fluid reservoir and move it through the top orifice. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a thorough understating of the present invention, reference is made to the following detailed description of the preferred embodiments, taken in conjunction with the accompanying drawings in which reference numbers designate like or similar elements throughout the several figures. Briefly: 
         FIG. 1  is cross section of an example wireline setting tool as it is lowered into a wellbore. 
         FIG. 2  is cross section of an example wireline setting tool partially stroked. 
         FIG. 3  is cross section of an example wireline setting tool after setting a plug. 
     
    
    
     DETAILED DESCRIPTION OF EXAMPLES OF THE INVENTION 
     In the following description, certain terms have been used for brevity, clarity, and examples. No unnecessary limitations are implied and such terms are used for descriptive purposes only and are intended to be broadly construed. The different apparatus and method steps described herein may be used alone or in combination with other systems and method steps. It is to be expected that various equivalents, alternatives, and modifications are possible within the scope of the presented claims. 
     An example embodiment is illustrated in the wireline setting tool  10  of  FIG. 1 . The setting tool  10  includes a top piston  11  located within the cylindrical body  12 . An orifice sub connects the cylindrical body  12  with the shear sub  14 . Power charge chamber  15  contains the gas generating energetic material  23 . Bottom piston  16  is located in the cylindrical body  12  opposite of top piston  11 . Top piston  11  has a mandrel  24  attached to the face  28  of the top piston  11 . Bottom piston  16  has a through bore  26  that slidably receives the mandrel  24 . Retainer sub  17  slidably engages the bottom piston  16  and limits the linear travel of bottom piston  16 . Attachment sub  18  interfaces the bottom piston  16  with the setting sleeve  20 . Top piston  11  and bottom piston  16 , combined with cylindrical body  12 , create a variable volume pressure chamber  27 . In this configuration a plug  22  is attached to the setting tool using a shear stud  29 . Shear stud  29  is connected to a connector sub  21 , which is then connected to the mandrel  24 . Pistons  11  and  16  can seal inside the body  12  using o-rings, piston rings, gaskets, or other well-known sealing methods. In typical operation a gas generating explosive material  23  is electrically ignited. The gases generated by the power charge  23  enters chamber  27  by way of the gas vent  28 , exerting pressure on top piston  11  and lower piston  16 . The pressure buildup in pressure chamber  27  causes lower piston  16  to move downward as shown in  FIG. 2 . Fluid  30  is held in a fluid reservoir  50  located between the piston body  32  and the cylindrical body  12 . The movement of lower piston  16  downward causes the fluid  30  to vent out of the setting tool  10  via vents in the retainer sub  17 . The fluid  30  could be any hydraulic fluid or other suitable fluid, such as oil, glycol, or water. Retainer sub  17  limits the downward travel of lower piston  16  with respect to the cylindrical body  12 . 
     Referring to  FIG. 2 , as the lower piston  16  slides downward relative to the mandrel  24 , it causes setting sleeve  20  to move downward as well, relative to the mandrel  24 . As the setting sleeve  20  moves downward it begins to collapse the plug  22  linearly, thereby causing it to expand radially. The center of plug  22  is held in place by mandrel  24 . The full stroke of lower piston  16  may be sufficient to set the plug  22 . 
     As the lower piston  16  bottoms out, the forces due to the pressure in chamber  27  will start to act against the cylindrical body  12  as it is still slidably engaged to upper piston  11  and cause the cylindrical body  12  to move in relation to upper piston  11 , further expanding chamber  27 . As the cylindrical body  12  moves downward relative to a stationary piston  11 , fluid  31  in fluid reservoir  49 , formed by piston  11  and cylindrical body  12 , is vented out of the setting tool  10  via an orifice or valve in orifice sub  13 . The fluid  31  could be any hydraulic fluid or other suitable fluid, such as oil, glycol, or water. 
     When sufficient pressure is generated in pressure chamber  27 , the bottom piston  16  will move downward as shown in  FIG. 2 . As bottom piston  16  moves downward, the mandrel  24  stays stationary, thus pulling the plug  22  through the setting sleeve  20 . This action causes the bridge plug to collapse against itself axially and expand outwardly to seal a borehole. The fluid  30  and fluid  31  provides resistance to the movement of upper piston  11  and lower piston  16  relative to the cylindrical body  12 , thus reducing dynamic loading effects of the rapid pressure buildup in chamber  27  and allowing the plug  22  to properly set with more controlled forces. 
     Referring to  FIG. 3 , as the shear sub  14  bottoms out against upper piston  11 , the setting tool  10  will be fully stroked. The full stroke of upper piston  11 , in combination with the full stroke of lower piston  16 , is sufficient to set the plug  22  and then separate the setting tool  10  from the plug  22  by shearing shear stud  29 . After this, the setting tool  10  can be removed from the cased wellbore, leaving behind plug  22 . 
     Another example embodiment may include a setting tool  10  with a substantially cylindrical body  12  with a center axis  40 , a first piston  11  slidably disposed within the cylindrical body  12 . The first piston  11  may have a first piston face  28  and a mandrel  24  extending normal from the first piston face  28  in a first direction downhole. The setting tool  10  may include a second piston  16  slidably disposed in the cylinder  12  and having a second piston face  41  and an axial through bore  26 . The mandrel  24  of the first piston  11  slidably engages through the axial through bore  26  of the second piston  16 . The first piston face  28 , the second piston face  41 , and the cylindrical body  12  in this example form a pressure chamber  27 . 
     A variation of this described embodiment may include the second piston  16  moving along the axis  40  in a first direction. The cylindrical body  12  may move along the axis  40  in the first direction. The embodiment may further have a shear stud  29  coupled to the bottom end of the mandrel  24 . The second piston  16  is located between the first piston  11  and the shear stud  29  along the mandrel  24 . The embodiment may further have an expandable plug  22  coupled to the shear stud  29 . The expandable plug  22  may be a bridge plug. The embodiment may further have a vent  42 . A fluid can enter the pressure chamber  27  via vent  42 . A first fluid reservoir  49  may be formed by the first piston  11  and the cylindrical body  12  and containing fluid  31 . A second fluid reservoir  50  is formed by the second piston  16  and the cylindrical body  12  and containing fluid  30 . Fluids  30  and  31  can be an oil, hydraulic fluid, glycerol, water, or other suitable fluids. 
     Another example embodiment may include a setting tool  10  having a cylindrical body  12  having a center axis  40 , a first end, a second end, an inner surface, and an outer surface, and a first piston  11  located within the cylindrical body  12 . The cylindrical body  12  and the first piston  11  may be axially aligned. The first piston  11  may have a first end and a second end, and a fluid passage  42  connecting the first end to the second end. A cylindrical mandrel  24  may extend from the second end of the first piston  11 . The mandrel  24  may be axially aligned with the cylindrical body  12 . The setting tool  10  may include a second piston  16  located within the cylindrical body  12  and axially aligned with the cylindrical body  12 . The second piston  16  may have an axial bore  26  throughout the length of the second piston  16 , with a first end and a second end. The first end of the second piston  16 , the second end of the first piston  11 , and the cylindrical body  12  may form a variable volume pressure chamber  27 . 
     A variation of the described embodiment may further include a cylindrical sub  13  connected to the first end of the cylindrical body  12  having at least one orifice  43  placing a first portion of the inside of the cylindrical body  12  in fluid communication with the outside of the cylindrical body. The embodiment may further have a retainer sub  17  connected to the second end of the cylindrical body  12  having at least one orifice  44  placing a second portion of the inside of the cylindrical body  12  in fluid communication with the outside of the cylindrical body  12 . The embodiment may further have a power charge chamber  15  located proximate to the cylindrical body  12 . Gases generated by the power charge can enter the fluid passage  42  of the first piston  11  at the first end and exit at the end of the fluid passage  42  at the second end, thus entering the variable volume pressure chamber  27 . It may further include a firing head  19  coupled to the power charge chamber  15 . The mandrel  24  may be disposed within the axial bore  26  of the second piston  16 . It may further have a retainer sub  17  coupled to the second end of the cylindrical body  12 . The retainer sub  17  limits the stroke of the second piston  16  with respect to the cylindrical body  12 . It may further have a cylindrical sub  13  coupled to the first end of the cylindrical body  12 . The cylindrical sub  13  limits the stroke of the second piston  16  with respect to the cylindrical body  12 . It may further have a setting sleeve  20  coupled to the second piston  16 . It may further have a connector sub  21  coupled to the mandrel  24 . It may further have a shear stud  29  coupled to the connector sub  21 . It may further have an expandable plug  22  coupled to the shear stud  29 . The first piston  11  may stay stationary while the second piston  16  and cylindrical body  12  each move axially away from the first piston  11 . The fluid passage  42  may provide fluid communication for a gas between the first end of the first piston  11  and the variable volume pressure chamber  27 . 
     Another example embodiment may include a method for setting a plug  22  in a borehole of activating a firing head  19 , starting a gas pressure generating chemical reaction, pressurizing a chamber  27  located within a cylindrical body  12  with the generated gas pressure, moving a piston  16  disposed within the cylinder in a first axial direction with the generated gas, and moving the cylindrical body  12  in the first axial direction with the generated gas. 
     A variation of the example includes placing a setting tool  10  in a borehole  45  at a predetermined location for installing a plug  22  against casing  46 . Moving the piston  11  in the first axial direction acts to evacuate a fluid  30  from the setting tool  10 . Moving the cylindrical body  12  in the first axial direction may evacuate a second quantity of oil  31  from the setting tool  10 . This will cause seal  47  to radially expand against an inner wall of a borehole casing  46 . The action may also shear a shear stud  29  coupled between a setting tool  10  and a setting plug  22 . After setting a plug  22  the setting tool  10  is removed from the borehole  45 . The radially expanded plug  22  as shown in  FIG. 2  may be a bridge plug. 
     Another example embodiment may include a setting tool  10  having a power charge chamber  15 , a cylindrical body  12  having a top end and a bottom end and a longitudinal axis  40  extending through its center from the top end to the bottom end. The setting tool  10  has a top piston  11 , with a top end and a bottom end corresponding with the top end and bottom end of the cylindrical body  12 . The top piston  11  slidably seals within the cylindrical body  12 . A bottom piston  16 , having a top end and a bottom end corresponding with the top end and bottom end of the cylindrical body  12 , is also located within cylindrical body  12 . Bottom piston  16  slidably seals within the cylindrical body  12 . A top piston mandrel  48  connects the power charge chamber  15  to the top end of the top piston through the top end of the cylindrical body  12 . A gas passage  42  through the top piston mandrel  48  provides fluid communication from the energetic material from the power charge chamber  15  to the pressure chamber  27 . A bottom piston mandrel  32  connects the bottom piston  16  to a setting sleeve  20 . A setting mandrel  24  extends from the bottom end of the top piston  11  through the bottom piston  16  and bottom piston mandrel  32 . The top piston  11 , bottom piston  16 , and cylindrical body  12  form pressure chamber  27 . 
     A variation of the example may further include a top fluid reservoir  49  formed between the top end of the top piston  11  and the top end of the cylindrical body  12 . It may further include a bottom fluid reservoir  50  formed between the bottom end of the bottom piston  16  and the top end of the cylindrical body  12 . It may further include a top orifice  43  located proximate to the top end of the cylindrical body  12  and adapted to release fluid  31  from the top fluid reservoir  49  under pressure. It may further include a bottom orifice  44  located proximate to the bottom end of the cylindrical body  12  and adapted to release fluid  30  from the bottom fluid reservoir  50  under pressure. It may further include a bottom sub  17  located proximate to the bottom end of the cylindrical body  12  and adapted to stop the bottom piston  16  from exiting the bottom end of the cylindrical body  12 . A top cylindrical sub  13  is located proximate to the top end of the cylindrical body  12  and is adapted to stop the top piston  11  from exiting the top of the cylindrical body  12 . The power charge chamber  15 , cylindrical body  12 , top piston  11 , and bottom piston  16  may all be coaxially aligned. The top piston mandrel  48 , bottom piston mandrel  32 , setting sleeve  20 , and setting mandrel  24  may all be coaxially aligned. Energetic charge  23  is disposed within the charge chamber  15 . The combustion of the energetic charge  23  creates gas that flows through the gas passage  42  to the pressure chamber  27 . The pressure created by the gas moves the bottom piston  16  toward the bottom sub  17  and moves the top end of the cylindrical body  12  down toward the top piston  11 . The bottom piston  16  may move toward the bottom sub  17  to pressurize fluid  30  in the bottom fluid reservoir  50 , thereby moving it through the bottom orifice  44 . The top end of the cylindrical body  12  may move toward the top piston  11  to pressurize fluid  31  in the top fluid reservoir  49 , thereby moving it through the top orifice  43 . 
     Although the invention has been described in terms of particular embodiments which are set forth in detail, it should be understood that this is by illustration only and that the invention is not necessarily limited thereto. For example, terms such as upper piston and lower piston can be substituted with top piston and bottom piston, respectfully. Top and bottom could be left and right. The alternative embodiments and operating techniques will become apparent to those of ordinary skill in the art in view of the present disclosure. Accordingly, modifications of the invention are contemplated which may be made without departing from the spirit of the claimed invention.