Controlled descent caged ball bypass plunger

Abstract

The present invention is related to a bypass plunger. The plunger includes a plurality of flow ports, a cage including a seat, a flow restriction member positioned within the cage, a choke passageway extending between the seat and a lower end of the plunger. The cage is located proximate the flow ports. The flow restriction member is movable between a seated position and an unseated position in response to formation contents flowed into the wellbore from a reservoir. The flow restriction member is the unseated position when the plunger descends down a wellbore and is the seated position when the plunger ascends in the wellbore. The flow ports, cage, and choke passageway are in fluid communication when the flow restriction member is in the unseated position. In the seated position, the flow restriction member is in physical contact with the seat. This configuration provides a bypass plunger with controlled descent.

What is claimed is: 
     
         1 . A plunger comprising:
 a body having an upper end and a lower end;   a plurality of flow ports on the upper end of the body, the flow ports extending through the body;   a case including a seat, the cage being located proximate the plurality of flow ports and configured to be in fluid communication with the plurality of flow ports;   a flow restriction member positioned within the case, wherein the flow restriction member is movable between a seated position and an unseated position such that the flow restriction member is in the unseated position when the plunger descends down a wellbore and is in the seated position when the plunger ascends in the wellbore, and wherein in the seated position the flow restriction member is in physical contact with the seat; and   a choke passageway extending between the seat and the lower end of the body, wherein the choke passageway is in fluid communication with the cage and the plurality of flow ports when the ball is unseated.   
     
     
         2 . The plunger of  claim 1 , wherein the number of the flow ports is between 2 and 5. 
     
     
         3 . The plunger of  claim 1 , wherein the flow ports have a helical shape. 
     
     
         4 . The plunger of  claim 1 , wherein the flow restriction member is a ball. 
     
     
         5 . The plunger of  claim 1 , further comprising a fishing neck configured to facilitate retrieval of the plunger from the wellbore. 
     
     
         6 . The plunger of  claim 1 , further comprising a plurality of exterior seal rings. 
     
     
         7 . The plunger of  claim 1 , wherein the body includes a first component and a second component, the first component includes the flow ports, the cage, and a fishing neck, and the second component includes the lower end. 
     
     
         8 . The plunger of  claim 7 , wherein the first component includes an opening to accommodate the second component. 
     
     
         9 . The plunger of  claim 8 , wherein the second component is configured to be inserted into the opening of the first component. 
     
     
         10 . The plunger of  claim 9 , wherein the second component further includes a region having a plurality of threads, fasteners, or other mechanisms capable of affixing the second component to a corresponding structure in the opening of the first component. 
     
     
         11 . The plunger of  claim 7 , wherein the second component further includes a region having a plurality of threads, fasteners, or other mechanisms capable of affixing the second component to the first component. 
     
     
         12 . The plunger of  claim 1 , wherein the body is coated with Nickel Boron or Electroless-Nickel. 
     
     
         13 . The plunger of  claim 1 , wherein the lower end of the body is configured to contact a bumper spring assembly. 
     
     
         14 . The plunger of  claim 1 , wherein the flow restriction member is configured to be movable in response to formation contents flowing into the wellbore from a reservoir. 
     
     
         15 . A method for lifting formation fluid out of a wellbore, comprising:
 introducing the plunger of  claim 1  into the wellbore with the lower end of the plunger entering the wellbore first;   allowing the plunger to descend to a bumper spring assembly, wherein the plunger descents at a speed determined by the size and number of the flow ports; and   allowing the plunger to ascend in the wellbore in response to formation contents flowing into the wellbore from a reservoir thereby pushing formation liquid above the plunger upward to a ground surface.   
     
     
         16 . A method for lifting formation fluid out of wellbore, comprising:
 introducing the plunger of  claim 1  into the wellbore with the lower end of the plunger entering the wellbore first;   allowing the plunger to descent to a bumper spring assembly, wherein the plunger descents at a speed determined by the size of the choke passageway; and   allowing the plunger to ascent in the wellbore in response to formation contents flowing into the wellbore from a reservoir thereby pushing formation liquid above the plunger upward to a ground surface.