Tool With Modular Pressure Compensator And Related Methods

Abstract

A tool which employs an internal fluid during operation in a subterranean environment at elevated pressures and/or temperatures, the tool including a modular pressure compensator component which can be easily and rapidly replaced as needed. Also described is a related method of maintaining a tool which employs an internal fluid during operation in a subterranean environment at one or more pressures above atmospheric pressure, and a related method of compensating for pressure changes within a tool which employs an internal fluid during operation in a subterranean environment at super-atmospheric pressures.

1 . A tool which employs an internal fluid during operation in a subterranean environment at one or more pressures above atmospheric pressure, the tool comprising:
 a primary tool housing which at least defines an internal fluid volume for containing the internal fluid;   a secondary volume-adjustable housing defining at least one adjustable volume, the secondary housing being sized and configured so that the adjustable volume is in fluid communication with only the internal fluid volume of the tool during operation of the tool; and   a coupling sized and configured to detachably attach the secondary volume-adjustable housing to a conduit in fluid communication with the internal fluid volume, so that the adjustable volume is placed in substantially sealed fluid communication with the internal fluid volume when the secondary volume-adjustable housing is exposed to one or more pressures of the external fluid;   
       wherein the tool defines a cavity that is in fluid communication with an external fluid from the subterranean environment during operation of the tool in the subterranean environment, so that during operation of the tool in the subterranean environment, the secondary volume-adjustable housing expands or contracts the adjustable volume in response to a pressure difference between the internal fluid and the external fluid within the cavity. 
     
     
         2 . The tool according to  claim 1 , wherein the coupling comprises a quick connect-type valve coupling. 
     
     
         3 . The tool according to  claim 1 , wherein the primary tool housing forms at least one exterior surface, wherein the cavity is defined by the primary tool housing and is accessible from the exterior surface of the primary tool housing, wherein the secondary volume-adjustable housing is disposed within the cavity, and wherein the coupling is sized and configured to detachably attach the secondary volume-adjustable housing to the conduit while the secondary volume-adjustable housing is disposed within the cavity, so that during operation of the tool in the subterranean environment the adjustable volume is placed in substantially sealed fluid communication with the internal fluid volume while the secondary volume-adjustable housing is exposed to one or more pressures of the external fluid within the cavity. 
     
     
         4 . The tool according to  claim 3 , wherein the coupling comprises a quick connect-type valve coupling. 
     
     
         5 . The tool according to  claim 4 , further comprising a cover plate sized and configured to engage with the primary tool housing and cover the cavity so that an exterior surface of the cover plate and at least a portion of the exterior surface of the primary tool housing are substantially flush with one another. 
     
     
         6 . The tool according to  claim 4 , wherein the secondary volume-adjustable housing comprises an assembly comprising a plurality of cylindrical segments aligned at their respective center points along an imaginary longitudinal axis and an end cap enclosing one end of the aligned plurality of cylindrical segments. 
     
     
         7 . The tool according to  claim 4 , wherein the secondary volume-adjustable housing comprises one or more bellows. 
     
     
         8 . The tool according to  claim 4 , wherein the secondary volume-adjustable housing comprises a bladder. 
     
     
         9 . The tool according to  claim 8 , further comprising a cover plate sized and configured to engage with the primary tool housing and cover the cavity so that an exterior surface of the cover plate and at least a portion of the exterior surface of the primary tool housing are substantially flush with one another. 
     
     
         10 . The tool according to  claim 1 , wherein the secondary volume-adjustable housing comprises a spring-biased piston seated within a piston cylinder, so that the cavity is defined by a face of the piston and a portion of the piston cylinder, and the secondary volume-adjustable housing is configured for detachable attachment to the primary housing, and further defines one or more passageways extending along a longitudinal axis of the secondary volume-adjustable housing and sized to receive at least one transmission line for the transmission of power and/or signals through the tool. 
     
     
         11 . The tool according to  claim 10 , further comprising a threaded cylindrical sleeve disposed around a portion of the secondary housing and configured so as to provide a threaded connection of the secondary housing to a portion of the primary housing and to urge engagement of the coupling to detachably attach the secondary volume-adjustable housing to the conduit. 
     
     
         12 . A method of maintaining a tool which employs an internal fluid during operation in a subterranean environment at one or more pressures above atmospheric pressure, the method comprising:
 placing a first secondary volume-adjustable housing within or adjacent to a cavity defined by the tool, the cavity being sized and configured to be in fluid communication with an external fluid from the subterranean environment during operation of the tool in the subterranean environment;   detachably coupling the first secondary volume-adjustable housing to a conduit so as to place at least one adjustable volume defined by the first secondary volume-adjustable housing in fluid communication with the internal fluid of the tool, and to substantially maintain a seal between the internal fluid of the tool and the external fluid when the tool in operation is exposed to the external fluid;   exposing the tool to the external fluid during subterranean operation of the tool, so that the first secondary volume-adjustable housing expands or contracts the adjustable volume in response to a pressure difference between the internal fluid and the external fluid;   recovering the tool from the subterranean environment and uncoupling the first secondary volume-adjustable housing from the conduit; and   detachably coupling to the conduit a second secondary volume-adjustable housing in replacement of the first secondary volume-adjustable housing so as to place at least one adjustable volume defined by the second secondary volume-adjustable housing in fluid communication with the internal fluid of the tool, and re-forming a seal between the internal fluid of the tool and the external fluid when the tool in operation is again exposed to the external fluid.   
     
     
         13 . The method according to  claim 12 , wherein the step of detachably coupling the first secondary volume-adjustable housing to the conduit is carried out by mating together compatible components of a quick connect-type valve coupling. 
     
     
         14 . The method according to  claim 12 , wherein the first secondary volume-adjustable housing is placed within the cavity, the cavity being both defined by a primary housing of the tool and accessible from an exterior surface of the primary housing, the method further comprising covering the cavity with a cover plate when the second volume-adjustable housing is coupled to the conduit, so that an exterior surface of the cover plate and at least a portion of the exterior surface of the tool are substantially flush with one another. 
     
     
         15 . The method according to  claim 14 , wherein each of the steps of detachably coupling the first secondary volume-adjustable housing to the conduit and detachably coupling the second secondary volume-adjustable housing to the conduit is carried out by mating together compatible components of a quick connect-type valve coupling. 
     
     
         16 . The method according to  claim 12 , wherein the uncoupling of the first secondary volume-adjustable housing from the conduit is carried out without de-pressurizing the internal fluid in the tool, the second secondary volume-adjustable housing contains a fluid under pressure when it is detachably coupled to the conduit, and the method further comprises maintaining internal fluid pressure in the tool during substitution of the second secondary volume-adjustable housing for the first secondary volume-adjustable housing. 
     
     
         17 . A method of compensating for pressure changes within a tool which employs an internal fluid during operation in a subterranean environment at one or more pressures above atmospheric pressure, the method comprising:
 placing a first secondary volume-adjustable housing within or adjacent to a cavity defined by the tool, the cavity being sized and configured to be in fluid communication with an external fluid from the subterranean environment during operation of the tool in the subterranean environment;   detachably coupling the first secondary volume-adjustable housing to a conduit so as to place at least one adjustable volume defined by the first secondary volume-adjustable housing in fluid communication with the internal fluid of the tool, and to substantially maintain a seal between the internal fluid of the tool and the external fluid when the tool in operation is exposed to the external fluid;   exposing the tool to the external fluid during subterranean operation of the tool, so that the first secondary volume-adjustable housing expands or contracts the adjustable volume in response to a pressure difference between the internal fluid and the external fluid;   recovering the tool from the subterranean environment and uncoupling the first volume-adjustable housing from the conduit; and   detachably coupling a second secondary volume-adjustable housing to the conduit in replacement of the first secondary volume-adjustable housing so as to place at least one adjustable volume defined by the second secondary volume-adjustable housing in fluid communication with the internal fluid of the tool, and re-forming a seal between the internal fluid of the tool and the external fluid when the tool in operation is again exposed to the external fluid.   
     
     
         18 . The method according to  claim 17 , wherein the first secondary volume-adjustable housing is coupled to the conduit by mating (a) a first mating component which is connected to the conduit and (b) a second mating component which is connected to the first secondary volume-adjustable housing, so as to form a quick connect valve coupling, and wherein the second volume-adjustable housing is coupled to the conduit by mating (c) the first mating component which is connected to the conduit and (d) a third mating component which is connected to the second secondary volume-adjustable housing, so as to form another quick connect valve coupling. 
     
     
         19 . The method according to  claim 18 , wherein the uncoupling of the first volume-adjustable housing from the conduit is carried out without de-pressurizing the internal fluid in the tool, the second volume-adjustable housing contains a fluid under pressure when it is detachably coupled to the conduit, and the method further comprises maintaining internal fluid pressure in the tool during substitution of the second volume-adjustable housing for the first volume-adjustable housing. 
     
     
         20 . The method according to  claim 17 , wherein the uncoupling of the first volume-adjustable housing from the conduit is carried out without de-pressurizing the internal fluid in the tool, the second volume-adjustable housing contains a fluid under pressure when it is detachably coupled to the conduit, and the method further comprises maintaining internal fluid pressure in the tool during substitution of the second volume-adjustable housing for the first volume-adjustable housing.