Oil or gas drilling tool block with textured coating

Abstract

An oil or gas tool block with an advanced textured coating produced by automated electro spark deposition equipment. A die insert includes a substrate onto which a gripping surface is formed. The gripping surface is a textured coating electro-deposited on the substrate. The textured coating includes a cobalt-based alloy supplied directly by the welding electrode, allowing the continuous build-up of material typically in the range of 0.001-0.040 inches. The cobalt-based alloy comprises a blend of chromium, cobalt, iron, manganese, molybdenum, nickel, and silicon. One or more die inserts, whether blank or textured, can be stacked to form a tool block. In a process for making the die insert, the substrate is texture-coated using electro-spark deposition in two passes, including a first coating pass and a second coating pass. Hard coating may follow to thereby form a gradient of layers.

I claim: 
     
         1 . A die insert, comprising:
 a substrate;   a gripping surface on said substrate, wherein said gripping surface is a textured coating electro-spark deposited on said substrate.   
     
     
         2 . The die insert of  claim 1 , wherein said textured coating includes a cobalt-based alloy comprising a blend of chromium, carbon, nickel, molybdenum, iron, silicon, and cobalt. 
     
     
         3 . The die insert of  claim 2 , wherein said blend consists of chromium in the range of 15-40%, cobalt in the range of 40-70%, iron in the range of 1-5%, manganese in the range of 0.1-1.0%, molybdenum in the range of 3-7%, nickel in the range of 1-5%, and less than 1.0% silicon. 
     
     
         4 . The die insert of  claim 2 , further comprising a hard coating on said textured coating. 
     
     
         5 . The die insert of  claim 4 , wherein said die insert is formed as a gradient, varying in hardness, respectively, from said substrate to said hard coating. 
     
     
         6 . The die insert of  claim 5 , wherein said hard coating consists of tungsten carbide in the range of 40.0-97.7%, cobalt in the range of 3.0-30%, 2.0% or less tantalum carbide, 5.1% or less chromium carbide, 4.5% or less chromium, and 5% or less vanadium carbide. 
     
     
         7 . The die insert of  claim 3 , wherein said blend is supplied by a welding electrode. 
     
     
         8 . The die insert of  claim 1 , wherein said textured coating is formed to a thickness in the range of 0.001-0.040 inches. 
     
     
         9 . A die insert, comprising:
 multiple substrates, wherein at least one of said substrates is a die blank and at least one of said substrates is a textured substrate having a gripping surface;   said substrates stacked to form a tool block, wherein each said die blank and each said textured substrate are stacked in alternation.   
     
     
         10 . The die insert of  claim 9 , wherein said gripping surface is a textured coating electro-spark deposited on said substrate. 
     
     
         11 . The die insert of  claim 10 , wherein said textured coating includes a cobalt-based alloy comprising a blend of chromium, carbon, nickel, molybdenum, iron, silicon, and cobalt. 
     
     
         12 . The die insert of  claim 11 , wherein said blend consists of chromium in the range of 15-40%, cobalt in the range of 40-70%, iron in the range of 1-5%, manganese in the range of 0.1-1.0%, molybdenum in the range of 3-7%, nickel in the range of 1-5%, and less than 1.0% silicon. 
     
     
         13 . The die insert of  claim 9 , further comprising a hard coating on said gripping surface. 
     
     
         14 . The die insert of  claim 9 , wherein said gripping surface is formed to a thickness in the range of 0.001-0.040 inches. 
     
     
         15 . A process for making a die insert, comprising the step of texture-coating a substrate by electro-spark deposition. 
     
     
         16 . The process of  claim 15 , wherein said substrate is texture-coated in two passes, including a first coating pass and a second coating pass. 
     
     
         17 . The process of  claim 16 , wherein said first coating pass further comprises the steps of:
 aligning said substrate on an electro-spark deposition equipment;   inserting a welding electrode into said electro-spark deposition equipment;   setting an applicator angle in relation to said substrate; and,   coating said substrate with said welding electrode.   
     
     
         18 . The process of  claim 17 , wherein said applicator angle is set in the range of 30 to 40 degrees in relation to said substrate. 
     
     
         19 . The process of  claim 16 , wherein said second coating pass further comprises the steps of:
 maintaining said substrate on said electro-spark deposition equipment;   setting said applicator angle in the range of 15 to 25 degrees in relation to said substrate; and,   coating said substrate with said welding electrode.   
     
     
         20 . The process of  claim 15 , further comprising the step of hard coating said die insert, wherein said die insert is formed as a gradient, varying in hardness, respectively, from said substrate to said hard coating.