Device and method for identifying conditional changes in a downhole tool string or bottom hole assembly

Abstract

Devices and methods are provided for identifying changes in conditions in a downhole tool string or bottom hole assembly (BHA), which may be caused directly by manipulations or actions of the tool string or BHA. These devices and methods allow improved control and decision-making by an operator of the tool string or BHA, without the need to remove the tool string or BHA from a borehole, such as a wellbore. The device may be incorporated into a standalone unit or device that can be incorporated into any existing BHA to enhance operational efficiency, or it may be built as an integral portion of the tool or BHA component.

What is claimed is: 
     
         1 . A device for indicating a change in an operating condition of a downhole tool string or bottom hole assembly (BHA), comprising:
 a barrel, comprising a top end, the top end adapted to interconnect to the downhole tool string or BHA;   a spring, adapted to interconnect to a downhole tool component and adapted to compress when the downhole tool component supports a weight of an object;   a piston and a bushing, the piston interconnected to the spring and adapted to move along the bushing when the spring compresses, the bushing sealing the barrel and preventing the piston from being forced out of the device when the spring compresses; and   a lid, interconnected to the piston and adapted to move from a first position to a second position when the piston moves along the bushing,   
       wherein the lid substantially allows flow of a working fluid of the downhole tool string or BHA along a predetermined flow path when the lid is in the first position, and 
       wherein the lid substantially restricts flow of the working fluid along the predetermined flow path when the lid is in the second position. 
     
     
         2 . The device of  claim 1 , further comprising a lid housing, wherein at least a portion of the predetermined flow path runs through the lid housing, and wherein the lid seals against the lid housing when the lid is in the second position. 
     
     
         3 . The device of  claim 1 , further comprising a rupture disc, adapted to rupture and permit free flow of the working fluid when a pressure of the working fluid exceeds a predetermined limit. 
     
     
         4 . The device of  claim 1 , wherein the lid is a drop door. 
     
     
         5 . The device of  claim 1 , wherein the downhole tool component is an external catch device. 
     
     
         6 . The device of  claim 1 , wherein the downhole tool component is an internal catch device. 
     
     
         7 . The device of  claim 1 , wherein the lid is a flapper, a dual flapper, or a set of gates. 
     
     
         8 . A method for detecting whether a target object is secured to a downhole tool component of a work string, comprising:
 a) lowering the downhole tool component into a borehole;   b) positioning the downhole tool component into an engaging position relative to the target object;   c) placing the work string in tension, whereby the downhole tool component supports a weight of the target object if the target object is secured to the downhole tool component;   d) initiating flow of a working fluid of the work string along a predetermined flow path through an indicator device, such that the indicator device substantially restricts flow of the working fluid along the predetermined flow path when the downhole tool component supports the weight of the target object and substantially allows flow of the working fluid along the predetermined flow path otherwise; and   e) measuring a pressure of the working fluid along the predetermined flow path.   
     
     
         9 . The method of  claim 8 , wherein the indicator device comprises a lid and a lid housing, wherein at least a portion of the predetermined flow path runs through the lid housing, and wherein the lid substantially restricts flow of the working fluid by sealing against the lid housing. 
     
     
         10 . The method of  claim 9 , wherein the lid is a drop door. 
     
     
         11 . The method of  claim 8 , wherein the indicator device comprises a rupture disc, adapted to rupture and permit free flow of the working fluid when a pressure of the working fluid exceeds a predetermined limit. 
     
     
         12 . The method of  claim 8 , wherein the downhole tool component is an external catch device. 
     
     
         13 . The method of  claim 8 , wherein the downhole tool component is an internal catch device. 
     
     
         14 . The method of  claim 8 , further comprising pulling or jarring loose the target object. 
     
     
         15 . A system for detecting a change in an operating condition of a downhole tool string or bottom hole assembly (BHA), comprising:
 an indicator device, comprising:
 a barrel, comprising a top end, the top end adapted to interconnect to the downhole tool string or BHA; 
 a spring, interconnected to a downhole tool component and adapted to compress when the downhole tool component supports a weight of an object; 
 a piston and a bushing, the piston interconnected to the spring and adapted to move along the bushing when the spring compresses, the bushing sealing the device and preventing the piston from being forced out of the device when the spring compresses; and 
 a lid, interconnected to the piston and adapted to move from a first position to a second position when the piston moves along the bushing, 
 wherein the lid substantially allows flow of a working fluid of the downhole tool string or BHA along a predetermined flow path when the lid is in the first position, and 
 wherein the lid substantially restricts flow of the working fluid along the predetermined flow path when the lid is in the second position; 
   a pump, pumping the working fluid along the flow path; and   a pressure gauge, measuring a pressure of the working fluid at the flow restriction point.   
     
     
         16 . The system of  claim 15 , further comprising a lid housing, wherein at least a portion of the predetermined flow path runs through the lid housing, and wherein the lid seals against the lid housing when the lid is in the second position. 
     
     
         17 . The system of  claim 15 , further comprising a rupture disc, adapted to rupture and permit free flow of the working fluid when a pressure of the working fluid exceeds a predetermined limit. 
     
     
         18 . The system of  claim 15 , wherein the lid is a drop door. 
     
     
         19 . The system of  claim 15 , wherein the downhole tool component is an external catch device. 
     
     
         20 . The system of  claim 15 , wherein the downhole tool component is an internal catch device.