Coated cylinder for walking beam compressor

Abstract

Various methods and device are provided for use in a walking beam compressor used in an oil well pump. In one embodiment, a walking beam compressor assembly is provided having a compressor configured to receive and compress gas. The compressor can be positioned around a piston rod movably disposed therethrough and can include a cylindrical housing having an interior surface that is coated with a self-lubricating composite material. The self-lubricating composite material can be impervious to gas such that it protects the interior surface of the cylindrical housing from corrosion by the gas. In one embodiment, the self-lubricating composite material can be a nickel ceramic composite. The cylindrical housing can be formed of any suitable material known in the art able to withstand pressure and heat within the housing, for example, a metallic material.

1 . A walking beam compressor assembly, comprising:
 a compressor configured to receive and compress gas, the compressor being positioned around a piston rod movably disposed therethrough and including a metallic cylindrical housing having an interior surface that is coated with a self-lubricating composite material that is impervious to gas such that the self-lubricating composite material protects the interior surface of the metallic cylindrical housing from corrosion by the gas.   
   
   
       2 . The walking beam compressor assembly of  claim 1 , wherein the self-lubricating composite material comprises a nickel ceramic composite. 
   
   
       3 . The walking beam compressor assembly of  claim 1 , wherein the metallic cylindrical housing is formed from steel. 
   
   
       4 . The walking beam compressor assembly of  claim 1 , wherein the coating of the self-lubricating composite material disposed on the interior surface of the metallic cylindrical housing has a thickness in the range of about 0.003 inches and 0.006 inches. 
   
   
       5 . The walking beam compressor assembly of  claim 1 , wherein an inner diameter of the coated interior surface of the metallic cylindrical housing is about 12 inches. 
   
   
       6 . The walking beam compressor assembly of  claim 1 , wherein an inner diameter of the coated interior surface of the metallic cylindrical housing is about 14 inches. 
   
   
       7 . The walking beam compressor assembly of  claim 1 , wherein the metallic cylindrical housing includes proximal and distal cylindrical rims coupled to top and bottom end plates. 
   
   
       8 . The walking beam compressor assembly of  claim 7 , wherein the top and bottom end plates include circumferential grooves for receiving top and bottom o-rings therein to form a seal within the metallic cylindrical housing. 
   
   
       9 . An oil well pump, comprising:
 a walking beam configured for driving a rod and plunger system to pump oil out of the ground;   a piston rod mated to the walking beam and extending vertically therefrom; and   a compressor mounted on the piston rod and having a cylindrical housing defining an interior surface, the interior surface having a coating disposed thereon and configured to prevent the metallic cylindrical housing from excessive frictional wear and corrosion.   
   
   
       10 . The oil well pump of  claim 9 , wherein the coating is a nickel ceramic composite. 
   
   
       11 . The oil well pump of  claim 9 , wherein the coating is a self-lubricating material. 
   
   
       12 . The oil well pump of  claim 9 , wherein the cylindrical housing is metallic. 
   
   
       13 . The oil well pump of  claim 12 , wherein the metallic cylindrical housing is formed from steel. 
   
   
       14 . The walking beam compressor assembly of  claim 9 , wherein the coating of the self-lubricating composite material disposed on the interior surface of the cylindrical housing has a thickness of between about 0.003 inches and 0.006 inches. 
   
   
       15 . The walking beam compressor assembly of  claim 9 , wherein an inner diameter of the coated interior surface of the cylindrical housing is selected from the group consisting of about 12 inches, 13 inches, and 14 inches. 
   
   
       16 . The oil well pump of  claim 9 , wherein the piston rod is configured for reciprocal longitudinal movement within the compressor. 
   
   
       17 . The oil well pump of  claim 9 , wherein the compressor is configured to receive and compress gas. 
   
   
       18 . The oil well pump of  claim 9 , wherein the metallic cylindrical housing includes proximal and distal cylindrical rims coupled to top and bottom end plates. 
   
   
       19 . The oil well pump of  claim 18 , wherein the top and bottom end plates include circumferential grooves for receiving top and bottom o-rings therein to form a seal within the cylindrical housing. 
   
   
       20 . A method of manufacturing a walking beam compressor, comprising:
 coating an interior surface of a cylindrical casing with a self-lubricating composite material that is impervious to gas;   truing the coating on the interior surface such the metallic cylindrical casing has a predetermined inner diameter; and   coupling the coated metallic cylindrical casing to a walking beam compressor.   
   
   
       21 . The method of  claim 20 , further comprising positioning the coated cylindrical casing around a compressing mechanism. 
   
   
       22 . The method of  claim 20 , further comprising coupling top and bottom end plates to top and bottom rims of the cylindrical casing. 
   
   
       23 . The method of  claim 22 , further comprising positioning o-rings between the top and bottom end plates and the interior surface of the cylindrical casing to provide a gas tight seal therebetween. 
   
   
       24 . The method of  claim 20 , further comprising positioning the assembled walking beam compressor around a piston rod extending from a walking beam. 
   
   
       25 . The method of  claim 20 , wherein the self-lubricating composite material is a nickel ceramic composite that protects the interior surface of the cylindrical casing from corrosion.