Hydraulic pump jack sytem for reciprocating oil well sucker rods

Abstract

A pumping system for vertical reciprocation of a string of sucker rods within oil well tubing having a positive displacement pump at the bottom thereof, includes a vertically positioned elongated hydraulic cylinder supported above the tubing and in alignment therewith, the cylinder having a vertically displaceable piston therein. A pump rod is affixed to the piston and extends beyond the bottom end of the cylinder. A seal member affixed to the lower end of the cylinder sealably and reciprocally receives the piston rod. A Tee fitting is secured between the tubing and the cylinder bottom end and reciprocally receives the piston rod. A controlled hydraulic power system provides fluid pressure to the cylinder to vertically reciprocate the piston and thereby the piston rod and tubing string to pump crude oil upwardly in the tubing, the crude oil flowing under pressure into the Tee fitting and out through a side opening.

1 . A pumping system for vertical reciprocation of a string of sucker rods in oil well tubing having a positive displacement pump at the bottom thereof, comprising: 
 a vertically positioned elongated hydraulic cylinder having a top and bottom end and supported above said tubing and in alignment therewith;    a vertically displaceable piston within said cylinder;    a pump rod affixed to said piston and extending beyond said cylinder bottom end;    a seal member affixed to said lower end of said cylinder for sealably and reciprocally receiving said piston rod;    a Tee fitting having a vertical passageway therethrough, having a lower open end secured to said tubing, an upper open end secured to said cylinder bottom end and a side opening communicating with said passageway that reciprocally receives said piston rod; and    a controlled hydraulic power system providing fluid pressure to said cylinder to vertically reciprocate said piston and thereby said piston rod and rod string to pump crude oil upwardly in the tubing, the crude oil flowing under pressure into said Tee fitting passageway and out through said side opening.    
   
   
       2 . A pumping system according to  claim 1  wherein said cylinder top end is vented to the atmosphere.  
   
   
       3 . A pumping system according to  claim 1  including: 
 a top seal affixed to said upper end of said cylinder;    an upper piston rod affixed to said piston and extending beyond said cylinder top end and sealably and reciprocally received by said top seal; and    wherein said hydraulic power system provides controlled fluid flow to said cylinder above and below said piston.    
   
   
       4 . A pumping system according to  claim 1  wherein said hydraulic power system is programmable permitting separate selectable upward and downward sucker rod acceleration rates.  
   
   
       5 . A pumping system according to  claim 4  wherein said hydraulic power system includes a program providing selectable delays at the top and/or bottom of sucker rod reciprocations.  
   
   
       6 . A pumping system according to  claim 1  including a sucker rod length adjustment mechanism between said pump rod and said sucker rod string.  
   
   
       7 . A pumping system according to  claim 6  including: 
 a vertical tubular adjustment member affixed at an upper end to said plumb rod and having a reduced internal diameter open lower end;    an externally threaded adjustment rod having an upper end portion received within said tubular adjustment member and a lower end affixed to the sucker rod string;    and    an internally threaded adjustment nut threadably received on said adjustment rod within said adjustment tubular member, the length of the sucker rod string be adjustable by the rotational position of said adjustment bolt.