Method of manufacturing continuous sucker rod

Abstract

A method for manufacturing a continuous sucker rod coil, wherein the method includes the step of selecting a plurality of input coils, each input coil having the same uniform hardness, and each input coil having two free ends. The method further includes the step of fusing adjacent free ends of adjacent input coils together to form one continuous length of rod, the fusing creating fused areas and a heat-affected zone at each fused area. The method also includes the step of treating each of the heat-affected zones to alleviate irregularities induced during fusing. Additionally, the method includes the step of winding the continuous length of rod into a finished coil.

What is claimed is: 
     
         1 . A system for manufacturing a continuous sucker rod coil, the system comprising:
 a single production line, comprising:
 a coil straightener configured to straighten input coils, each input coil having the same uniform hardness; 
 a welding machine that is configured to:
 fuse adjacent input coils together to form one continuous length of fused input coils, wherein fusing creates a heat-affected zone at each fused joint; and 
 treat the heat-affected zones to alleviate irregularities induced during fusing, wherein the welding machine selectively treats sections of the fused input coils to form treated sections and untreated sections; 
 
 a flaw detection system for inspecting a surface of the straightened coils; 
 a surface treating machine configured to clean a surface of the input coils and induce compressive stress in the surface; and 
 a transport reel to receive the continuous length of fused coils. 
   
     
     
         2 . The system of  claim 1 , wherein the single production line consists of a single welding machine. 
     
     
         3 . The system of  claim 1 , wherein the welding machine receives the straightened input coils directly from the coil straightener. 
     
     
         4 . The system of  claim 1 , wherein the surface treating machine receives the input coils directly from the welding machine. 
     
     
         5 . The system of  claim 1 , wherein the flaw detection system receives the straightened coils directly from the surface treating machine. 
     
     
         6 . The system of  claim 1 , wherein the surface treating machine receives the input coils directly from the coil straightener. 
     
     
         7 . The system of  claim 1 , wherein the flaw detection system comprises an eddy current sensor. 
     
     
         8 . The system of  claim 1 , wherein welding machine receives the straightened coils directly from the flaw detection system. 
     
     
         9 . The system of  claim 1 , wherein the welding machine is a flash butt welder. 
     
     
         10 . The system of  claim 1 , wherein the straightener is a cold straightener. 
     
     
         11 . The system of  claim 1 , further comprising flaw marking equipment and a digital encoder. 
     
     
         12 . The system of  claim 1 , wherein the flaw marking equipment is positioned downstream of the welding machine. 
     
     
         13 . The system of  claim 1 , wherein the flaw marking equipment is positioned upstream of the welding machine.