Positive displacement dump bailer

Abstract

A system and method for injecting bailer content utilizing a dump bailer having an elongated, flexible bailer receptacle secured between a head assembly and an injection assembly. Disposed within the dump bailer are first and second piston assemblies, each of which includes a piston having a central fluid passage with a pressure actuated flow control mechanism in the form of a rupture disk disposed along the fluid passage of the piston. An electric, positive displacement pump within the head assembly draws wellbore fluid into the dump bailer assembly to drive the first piston assembly towards the second piston assembly so as to release bailer content into a wellbore. The elongated flexible bailer receptacle may be a hose stored on a bailer receptacle reel, which hose may be paid out by the reel to a length that corresponds with a volume of bailer content to be released into the wellbore.

What is claimed: 
     
         1 . A dump bailer system comprising
 a tool body having a first end, a second end and an exterior;   an elongated bailer receptacle, carried by the tool body and having a cavity formed within the receptacle, the cavity having a first end and a second end,   a piston assembly slidably disposable within the cavity and movable between the first end and the second end of the cavity; and   a pump carried by the tool body and in fluid communication with the first end of the cavity.   
     
     
         2 . The dump bailer system of  claim 1 , wherein the pump is an electric, positive displacement pump. 
     
     
         3 . The dump bailer system of  claim 2 , wherein the pump is reversible. 
     
     
         4 . The dump bailer system of  claim 1 , wherein the tool body comprises a head assembly attached to the elongated bailer receptacle adjacent the first end of the cavity and an injection assembly attached to the elongated bailer receptacle adjacent the second end of the cavity, wherein the head assembly comprises the pump. 
     
     
         5 . The dump bailer system of  claim 4 , wherein head assembly further comprises a fluid passage formed within the tool body and extending from the exterior of the tool body to the first end of the cavity, wherein the positive displacement pump is disposed along the fluid passage. 
     
     
         6 . The dump bailer system of  claim 5 , wherein the head assembly further comprises a fluid filter disposed along the fluid passage between the exterior of the tool body and the first end of the cavity. 
     
     
         7 . The dump bailer system of  claim 1 , wherein the piston assembly comprises a first piston having a first side and a second side and an exterior surface, with a piston fluid passage extending between the first and second sides; and a rupture disk disposed along the fluid passage. 
     
     
         8 . The dump bailer system of  claim 7 , further comprising a second piston assembly having a second piston with a first side and a second side and an exterior surface, with a piston fluid passage extending between the first and second sides of the second piston; and a rupture disk disposed along the fluid passage of the second piston. 
     
     
         9 . The dump bailer system of  claim 8 , wherein the head assembly further comprises a tubular filling chamber having a first end and a second end, with the second end of the of the tubular filling chamber attached to the elongated bailer receptacle adjacent the first end of the cavity, the tubular filling chamber having a first piston assembly disposed adjacent the first end of the filling chamber, a second piston assembly disposed adjacent the second end of the filling chamber, and a fluid filling port disposed in the tubular filling chamber between the first and second piston assemblies. 
     
     
         10 . The dump bailer system of  claim 1 , further comprising an integral vibrator. 
     
     
         11 . The dump bailer system of  claim 1 , wherein the elongated bailer receptacle is a rigid receptacle. 
     
     
         12 . The dump bailer system of  claim 1 , wherein the elongated bailer receptacle is flexible. 
     
     
         13 . A dump bailer system comprising
 a tool body having a first end, a second end and an exterior, wherein the tool body comprises a head assembly with a fluid passage formed within the tool body and extending from the exterior of the tool body through the head assembly;   a flexible, elongated bailer receptacle, carried by the tool body and having a cavity formed within the receptacle, the cavity having a first end and a second end, wherein the head assembly is attached to the elongated bailer receptacle adjacent the first end of the cavity, and the fluid passage formed within the tool body extends from the exterior of the tool body to the first end of the cavity, and wherein the flexible, elongated bailer receptacle is a hose;   a piston assembly slidably disposable within the cavity and movable between the first end and the second end of the cavity, wherein the piston assembly comprises a first piston having a first side and a second side and an exterior surface, with a piston fluid passage extending between the first and second sides; and pressure actuated flow control mechanism disposed along the fluid passage of the piston; and   an electric, positive displacement pump carried by the tool body and in fluid communication with the first end of the cavity, wherein the positive displacement pump is disposed along the fluid passage.   
     
     
         14 . The dump bailer system of  claim 13 , wherein the hose comprises at least one woven outer flexible layer and at least one rubber inner flexible layer. 
     
     
         15 . The dump bailer system of  claim 13 , wherein the pump is reversible. 
     
     
         16 . A method for injecting bailer content into a wellbore, the method comprising: charging bailer content into an elongated dump bailer assembly; deploying the dump bailer assembly into a wellbore; and operating a pump carried by the dump bailer assembly to drive the bailer content from the dump bailer assembly. 
     
     
         17 . The method of  claim 16 , wherein operating the pump comprises pumping wellbore fluid from around the dump bailer assembly to drive a piston within the dump bailer assembly towards a downhole end of the dump bailer assembly; and utilizing the driven piston to urge the bailer content from the dump bailer assembly. 
     
     
         18 . The method of  claim 17 , wherein the step of pumping the wellbore fluid comprises pumping the wellbore fluid at a first pressure to drive the piston; and utilizing the driven piston to increase the fluid pressure of the bailer content; and utilizing the increased fluid pressure of the bailer content to actuate a flow control mechanism to inject the bailer content into the wellbore. 
     
     
         19 . The method of  claim 18 , wherein the step of pumping the wellbore fluid further comprises pumping the wellbore fluid at a second pressure greater than the first wellbore fluid pressure; utilizing the second pressure to actuate a flow control mechanism disposed within the piston; and pumping the wellbore fluid through the flow control mechanism of the piston to flush the bump bailer assembly. 
     
     
         20 . The method of  claim 19 , wherein the step of pumping the wellbore fluid further comprises reversing direction of the pumped wellbore fluid to create a low pressure on the piston; and driving the piston towards an uphole end of the dump bailer assembly.