Plunger Lift Apparatus

Abstract

A plunger of improved construction for reciprocating in a production string of a gas or oil well to remove fluid from the well. The plunger includes a sleeve having a through passage extending longitudinally from a first end to a second end, the second end forming a seat, a sealing means carried by the sleeve for engaging the inner surface of the production string, a detachable valve member releasably received by the seat to seal the through passage, and a catch positioned to releasably couple the detachable valve member to the sleeve within the seat. The catch retaining the detachable valve member until the detachable valve member is impacted at the surface of the well by a trip rod. The improved construction provides for the use of a heavier or more dense detachable valve member and a lighter or less dense sleeve than previously used in prior plungers, which results in a plunger having an increased efficiency and a greater cycle frequency.

1 . A plunger for reciprocating in a production string of a gas or oil well to remove fluid from the well, the well including a trip rod at the surface, the plunger comprising: 
 a sleeve having a through passage extending longitudinally from a first end to a second end thereof, said second end forming a seat;    sealing means carried by said sleeve for engaging the inner surface of the production string;    a detachable valve member releasably received by said seat to seal said passage; and    a catch positioned to releasably couple said detachable valve member to said sleeve within said seat, said catch retaining said detachable valve member until said detachable valve member is impacted at the surface of the well by the trip rod.    
   
   
       2 . The plunger of  claim 1 , wherein said catch is a magnetic catch positioned to attract and retain said detachable valve member within said seat.  
   
   
       3 . The plunger of  claim 2 , wherein said magnet encircles said detachable valve member when said detachable valve member is within said seat.  
   
   
       4 . The plunger of  claim 2 , wherein said magnet is flush with the surface of said seat.  
   
   
       5 . The plunger of  claim 4 , wherein said plunger further comprises: 
 a coating applied over said magnet and a least partially over the surface of said seat.    
   
   
       6 . The plunger of  claim 1 , wherein said catch is resiliently biased.  
   
   
       7 . The plunger of  claim 6 , wherein said catch includes spring loaded detents.  
   
   
       8 . The plunger of  claim 1 , wherein said first end defines an internal fishing neck.  
   
   
       9 . The plunger of  claim 1 , further comprising: 
 a resilient seal received by a groove formed around the surface of said seat and sized so that it sealing abuts said detachable valve member when said detachable valve member is within said seat.    
   
   
       10 . The plunger of  claim 1 , wherein said detachable valve member is a sphere.  
   
   
       11 . The plunger of  claim 10 , wherein said seat defines a spherical surface for at least partially receiving said detachable valve member.  
   
   
       12 . The plunger of  claim 1 , wherein said detachable valve member comprises a bullet shaped body having a spherical end.  
   
   
       13 . The plunger of  claim 12 , wherein said seat defines a spherical surface for at least partially receiving said spherical end of said bullet shaped body.  
   
   
       14 . A plunger for reciprocating in a production string of a gas or oil well to remove fluid from the well, the plunger comprising: 
 a sleeve having a through passage extending longitudinally from a first end to a second end thereof, said second end forming a seat having a spherical surface;    sealing means carried by said sleeve for engaging the inner surface of the production string;    a detachable valve member releasably received by said seat to seal said passage;    a catch positioned to releasably couple said detachable valve member to said sleeve within said seat; and    an resilient seal received by a groove formed around the surface of said seat and sized so that it sealing abuts said detachable valve member when said detachable valve member is within said seat.    
   
   
       15 . The plunger of  claim 14 , wherein said catch is a magnetic catch positioned to attract and retain said detachable valve member within said seat.  
   
   
       16 . The plunger of  claim 2 , wherein said magnet encircles said detachable valve member when said detachable valve member is within said seat.  
   
   
       17 . The plunger of  claim 1 , wherein said catch is resiliently biased.  
   
   
       18 . The plunger of  claim 6 , wherein said catch includes spring loaded detents.  
   
   
       19 . The plunger of  claim 1 , wherein said detachable valve member is a sphere.  
   
   
       20 . The plunger of  claim 1 , wherein said detachable valve member comprises a bullet shaped body having a spherical end.