Method of circulating through a reciprocating downhole tubing pump and a reciprocating downhole tubing pump

Abstract

A method of circulating through a reciprocating downhole tubing pump and a reciprocating downhole tubing pump. The reciprocating downhole tubing pump has a standing valve assembly and a travelling valve. The method involves displacing and disabling, without removing, the standing ball valve assembly and the travelling valve. This can be done with pins which knock the balls out of position or by enclosing the balls in cages which can be mechanically moved out of position with linkages. With the standing ball valve assembly and the travelling valve disabled, circulation can occur through the reciprocating downhole tubing pump. This has a number of advantages, such as removal of blockages due to sand accumulation.

1 . A method of circulating through a reciprocating downhole tubing pump which has a standing ball valve and a travelling ball valve positioned downhole, comprising the steps of: 
 providing first means for mechanically displacing and disabling, without removing, a ball from a ball seat on the travelling ball valve;    providing second means for mechanically displacing and disabling, without removing, a ball from a ball seat on the standing valve assembly; and    activating the first means to prevent the ball from engaging the ball seat on the travelling ball valve and the second means to prevent the ball from engaging the ball seat on the standing ball valve assembly and circulating fluids through both the travelling ball valve and the standing ball valve assembly.    
   
   
       2 . A reciprocating downhole tubing pump, comprising: 
 a barrel;    a piston axially movable along the barrel;    a travelling ball valve carried by the piston, the travelling valve having a ball seat which receives a ball;    a first means for mechanically displacing and disabling, without removing, the ball from the ball seat on the travelling ball valve;    a standing ball valve assembly positioned within the barrel, the standing ball valve assembly including a ball seat which receives a ball;    a second means for mechanically displacing and disabling, without removing, the ball from the ball seat on the standing valve assembly; and    means for activating the first means to prevent the ball from engaging the ball seat on the travelling ball valve and the second means to prevent the ball from engaging the ball seat on the standing ball valve assembly, such that a circulation of fluids can occur through both the travelling ball valve and the standing ball valve assembly.    
   
   
       3 . A method of circulating through a reciprocating downhole tubing pump which has a standing ball valve and a travelling ball valve positioned downhole, comprising the steps of: 
 providing displacing means on top of the standing ball valve assembly for displacing a ball from a ball seat on the travelling ball valve when the travelling ball valve is lowered onto the standing ball valve assembly;    providing a linkage for displacing a ball from a ball seat on the standing valve assembly, the linkage being engaged to displace the ball when the travelling ball valve is lowered onto the standing ball valve assembly; and    lowering the travelling ball valve onto the standing ball valve assembly, such that the displacing means extends through the valve seat to prevent the ball from engaging the ball seat on the travelling ball valve and the travelling valve acts upon the linkage to prevent the ball from engaging the ball seat on the standing ball valve assembly, thereby permitting an unfettered circulation of fluids through both the travelling ball valve and the standing ball valve assembly.    
   
   
       4 . A method of circulating through a reciprocating downhole tubing pump which has a standing ball valve and a travelling ball valve positioned downhole, comprising the steps of: 
 providing a standing ball valve assembly that has: 
 an upstanding first pin secured on top of the standing ball valve assembly, the first pin being in axial alignment with a ball seat which receives a ball on the travelling ball valve;  
 a ball seat which receives a ball, the ball being confined within a ball cage;  
 a pivot linkage adapted to pivot the ball cage from an operative position to a circulating position in which the ball cage is raised and the ball on the standing ball valve assembly is lifted by the ball cage off the ball seat; and  
   lowering the travelling ball valve onto the standing ball valve assembly, such that the first pin extends through the valve seat to prevent the ball from engaging the ball seat on the travelling ball valve and the travelling valve acts upon the pivot linkage to pivot the ball cage to the circulating position to prevent the ball from engaging the ball seat on the standing ball valve assembly, thereby permitting an unfettered circulation of fluids through both the travelling ball valve and the standing ball valve assembly.    
   
   
       5 . A method of circulating through a reciprocating downhole tubing pump which has a standing ball valve and a travelling ball valve positioned downhole, comprising the steps of: 
 providing a standing ball valve assembly that has: 
 an upstanding first pin secured on top of the standing ball valve assembly, the first pin being in axial alignment with a ball seat which receives a ball on the travelling ball valve;  
 a ball seat which receives a ball, the ball being confined within a ball cage;  
 a rigid pivot linkage having a first end and a second end, the first end being secured to the ball cage with a fulcrum positioned between the first end and the second end, such that when a downward force is exerted on the second end of the pivot linkage, the pivot linkage pivots about the fulcrum lifting the ball cage from an operative position to a circulating position in which the raised ball cage lifts the ball on the standing ball valve assembly from the ball seat;  
 an upstanding second pin secured to the second end of the pivot linkage and extending above the standing ball valve assembly adjacent to the first pin; and  
   lowering the travelling ball valve onto the standing ball valve assembly, such that the first pin extends through the valve seat to prevent the ball from engaging the ball seat on the travelling ball valve and the second pin acts upon the pivot linkage to pivot the ball cage to the circulating position to prevent the ball from engaging the ball seat on the standing ball valve assembly, thereby permitting an unfettered circulation of fluids through both the travelling ball valve and the standing ball valve assembly.    
   
   
       6 . A reciprocating downhole tubing pump, comprising: 
 a barrel;    a travelling ball valve axially movable along the barrel, the travelling valve having a ball seat which receives a ball;    a standing ball valve assembly positioned within the barrel, the standing ball valve assembly including a ball seat which receives a ball, the ball being confined within a ball cage;    an upstanding first pin secured on top of the standing ball valve assembly, the first pin being in axial alignment with a ball seat which receives a ball on the travelling ball valve;    a rigid pivot linkage having a first end and a second end, the first end being secured to the ball cage with a fulcrum positioned between the first end and the second end, such that when a downward force is exerted on the second end of the pivot linkage, the pivot linkage pivots about the fulcrum lifting the ball cage from an operative position to a circulating position in which the raised ball cage lifts the ball on the standing ball valve assembly from the ball seat; and    an upstanding second pin secured to the second end of the pivot linkage and extending above the standing ball valve assembly adjacent to the first pin, such that when the travelling ball valve is lowered onto the standing ball valve assembly the first pin extends through the valve seat to prevent the ball from engaging the ball seat on the travelling ball valve and the second pin acts upon the pivot linkage to pivot the ball cage to the circulating position to prevent the ball from engaging the ball seat on the standing ball valve assembly, thereby permitting an unfettered circulation of fluids through both the travelling ball valve and the standing ball valve assembly.    
   
   
       7 . The reciprocating downhole tubing pump as defined in  claim 6 , wherein a screen is positioned below the standing ball valve assembly.  
   
   
       8 . A method of circulating through a reciprocating downhole tubing pump which has a standing ball valve and a travelling ball valve positioned downhole, comprising the steps of: 
 providing a standing ball valve assembly that is axially movable along a barrel of the downhole tubing pump with axial travel being limited by an underlying axial stop, an upstanding first pin being secured on top of the standing ball valve assembly, the first pin being in axial alignment with a ball seat which receives a ball on the travelling ball valve;    securing an upstanding second pin below the standing ball valve assembly, the second pin protruding above the axial stop in axial alignment with a ball seat which receives a ball on the standing ball valve assembly;    positioning a spring between the standing ball valve and the axial stop, the spring biasing the standing ball valve assembly into an operative position spaced above the second pin, upon the spring being compressed the standing ball valve assembly assuming a circulating position with the second pin preventing the ball from engaging the ball seat on the standing ball valve assembly; and    lowering the travelling ball valve onto the standing ball valve assembly and exerting a compressive force upon the spring to move the standing ball valve assembly to the circulating position, such that the first pin prevents the ball from engaging the ball seat on the travelling ball valve and the second pin prevents the ball from engaging the ball seat on the standing ball valve assembly, thereby permitting an unfettered circulation of fluids through both the travelling ball valve and the standing ball valve assembly.    
   
   
       9 . The method as defined in  claim 8 , the compressive force being provided by a weight of a tubing string.  
   
   
       10 . The method as defined in  claim 8 , the compressive force being provided by fluid under pressure.  
   
   
       11 . A reciprocating downhole tubing pump, comprising: 
 a barrel;    a travelling ball valve axially movable along the barrel, the travelling valve having a ball seat which receives a ball;    a standing ball valve assembly axially movable along the barrel with axial travel being limited by an underlying axial stop, the standing ball valve assembly having a ball seat which receives a ball;    an upstanding first pin secured on top of the standing ball valve assembly, the first pin being in axial alignment with the ball seat on the standing ball valve assembly;    an upstanding second pin below the standing ball valve assembly, the second pin protruding above the axial stop in axial alignment with the ball seat on the standing ball valve assembly; and    a spring between the standing ball valve and the axial stop, the spring biasing the standing ball valve assembly into an operative position spaced above the second pin, such that, upon the travelling ball valve contacting the standing ball valve assembly and a compressive force being exerted upon the spring, the standing ball valve assembly is moved to a circulating position with the first pin preventing the ball from engaging the ball seat on the travelling ball valve and the second pin preventing the ball from engaging the ball seat on the standing ball valve assembly, thereby permitting an unfettered circulation of fluids through both the travelling ball valve and the standing ball valve assembly.