Production Plunger

A plunger for reciprocating in a production string of a well to unload the well of formation fluid to increase well production, the plunger comprising:

• a body for reciprocating in a production string of a well, said body having a passage extending longitudinally through said body;
• a valve seat in said passage;
• a valve seal positioned in said passage;
• a valve rod connected to said valve seal and extending through said valve seat in said passage;
• a piston connected to said valve rod;
• means containing air under pressure connected to said piston and urging said valve seal away from said valve seat;
• resilient means connected to said piston and urging said valve seal towards said valve seat;
• locking means for releasable engagement with said valve rod to resiliently lock said valve rod in a first position where said valve seal is away from said valve seat and to resiliently lock said valve rod in a second position where said valve seal is in sealing contact with said valve seat;
• seal means carried by said body for engaging the inner wall of the production string and preventing fluid in the production string from flowing through the production string between said body and the inner wall of the production string;
• and
• said body defining a first opening on a first side of said valve seat through which formation fluid can flow into said passage, across said valve seat and out of said passage through a second opening defined by said body on a second side of said valve seat until a quantity of formation fluid is accumulated which is sufficient to compress the air contained by said means for containing air, and to release said locking means from said valve rod to position said valve seal in sealing contact with said valve seat, thereby allowing gas pressure below said seal means to move said body and the accumulated formation fluid to the surface of the well.

A plunger for reciprocating in a production string of a well to unload the well of formation fluid to increase well production, the plunger comprising:

• a body for reciprocating in a production string of a well, said body having a passage extending longitudinally through said body;
• a valve seat in said passage;
• a valve seal positioned in said passage;
• a valve rod connected to said valve seal and extending through said valve seat in said passage;
• a piston connected to said valve rod;
• a collapsible means containing air under pressure connected to said piston and urging said valve seal away from said valve seat;
• resilient means connected to said piston and urging said valve seal towards said valve seat;
• locking means for releasable engagement with said valve rod to resiliently lock said valve rod in a first position where said valve seal is away from said valve seat and to resiliently lock said valve rod in a second position where said valve seal is in sealing contact with said valve seat;
• seal means carried by said body for engaging the inner wall of the production string and preventing fluid in the production string from flowing through the production string between said body and the inner wall of the production string;
• first and second centralizers positioned at opposite ends of said body;
• a retrieval means attached to said body for use in retrieving said body from the production string;
• and
• said body defining a first opening on a first side of said valve seat through which formation fluid can flow into said passage, across said valve seat and out of said passage through a second opening defined by said body on a second side of said valve seat until a quantity of formation fluid is accumulated which is sufficient to compress the air contained by said means for containing air, and to release said locking means from said valve rod to position said valve seal in sealing contact with said valve seat, thereby allowing gas pressure below said seal means to move said body and the accumulated formation fluid to the surface of the well.