Methods of making a drilling tool with low friction coatings to reduce balling and friction

Abstract

Provided are methods to make a drilling tool with low friction coatings to reduce balling and friction. In one form, the method includes providing one or more drilling tool components with specified locations for fitting cutters, inserts, bearings, rollers, additional non-coated components, or combinations thereof; cleaning the one or more drilling tool components; applying masking for fitting cutters, inserts, bearings, rollers, additional non-coated components or combinations thereof; applying a multi-layer low friction coating to the cleaned specified locations; removing the masking from the cleaned and coated specified locations of the one or more drilling components; inserting cutters and inserts and assembling moving parts to the cleaned and coated specified locations of the one or more drilling tool components; and assembling the one or more drilling tool components to form a drilling tool.

What is claimed is: 
     
         1 . A method of manufacturing a drilling tool comprising:
 providing one or more drilling tool components with specified locations for fitting cutters, inserts, bearings, rollers, additional non-coated components, or combinations thereof;   cleaning said one or more drilling tool components with specified locations to remove oil, organic compounds, and/or adsorbates;   applying masking to said cleaned specified locations for fitting cutters, inserts, bearings, rollers, additional non-coated components or combinations thereof;   applying a multi-layer low friction coating to said cleaned specified locations, wherein said multi-layer low friction coating comprises:
 i) an under layer selected from the group consisting of CrN, TiN, TiAlN, TiAlVN, TiAlVCN, TiSiN, TiSiCN, TiAlSiN and combinations thereof, wherein the under layer ranges in thickness from 0.1 to 100 μm, 
 ii) an adhesion promoting layer selected from the group consisting of Cr, Ti, Si, W, CrC, TiC, SiC, WC, and combinations thereof, wherein the adhesion promoting layer ranges in thickness from 0.1 to 50 μm and is contiguous with a surface of the under layer, and 
 iii) a functional layer selected from the group consisting of a fullerene based composite, graphene, a diamond based material, diamond-like-carbon (DLC), and combinations thereof, wherein the functional layer ranges from 0.1 to 50 μm and is contiguous with a surface of the adhesion promoting layer. 
 wherein the adhesion promoting layer is interposed between the under layer and the functional layer, 
 wherein the coefficient of friction of the functional layer of the low friction coating as measured by the block on ring friction test is less than or equal to 0.15, and 
 wherein the abrasion resistance of the low friction coating as measured by the modified ASTM G105 abrasion test yields a wear scar depth of less than or equal to 20 μm and a weight loss less than or equal to 0.03 grams; 
 removing the masking from said cleaned and coated specified locations of said one or more drilling components; 
 inserting cutters and inserts and assembling moving parts to the cleaned and coated specified locations of the one or more drilling tool components; and 
 assembling the one or more drilling tool components to form a drilling tool. 
   
     
     
         2 . The method of  claim 1 , wherein the under layer is contiguous with a surface of a substrate. 
     
     
         3 . The method of  claim 2 , wherein the substrate is selected from the group consisting of steel, stainless steel, hardbanding, an iron alloy, an aluminum based alloy, a titanium based alloy, ceramics and a nickel based alloy. 
     
     
         4 . The method of  claim 3 , wherein the hardbanding comprises a cermet based material, a metal matrix composite or a hard metallic alloy. 
     
     
         5 . The method of  claim 1 , wherein the functional layer is a diamond based material. 
     
     
         6 . The method of  claim 5 , wherein the diamond based material is chemical vapor deposited (CVD) diamond or polycrystalline diamond compact (PDC). 
     
     
         7 . The method of  claim 1 , wherein the functional layer is diamond-like-carbon (DLC). 
     
     
         8 . The method of  claim 7 , wherein the diamond-like-carbon (DLC) is selected from the group consisting of ta-C, ta-C:H, DLCH, PLCH, GLCH, Si-DLC, N-DLC, O-DLC, B-DLC, Me-DLC, F-DLC and combinations thereof. 
     
     
         9 . The method of  claim 1 , wherein the under layer hardness ranges from 800 to 3500 VHN. 
     
     
         10 . The method of  claim 1 , wherein the adhesion promoting layer hardness ranges from 200 to 2500 VHN. 
     
     
         11 . The method of  claim 1 , wherein the functional layer hardness ranges from 1000 to 7500 VHN. 
     
     
         12 . The method of  claim 1 , further including a gradient at the interface of the under layer and the adhesion promoting layer ranging from 0.01 to 10 μm. 
     
     
         13 . The method of  claim 1 , further including a gradient at the interface of the adhesion promoting layer and the functional layer ranging from 0.01 to 10 μm. 
     
     
         14 . The method of  claim 1 , further including a second adhesion promoting layer selected from the group consisting of Cr, Ti, Si, W, CrC, TiC, SiC, WC, and combinations thereof, wherein the second adhesion promoting layer ranges in thickness from 0.1 to 50 μm and is contiguous with a surface of the functional layer, and a second functional layer selected from the group consisting of a fullerene based composite, graphene, a diamond based material, diamond-like-carbon (DLC), and combinations thereof, wherein the second functional layer ranges from 0.1 to 50 μm and is contiguous with a surface of the second adhesion promoting layer. 
     
     
         15 . The method of  claim 14 , further including a second under layer interposed between the functional layer and the second adhesion promoting layer, wherein the second under layer is selected from the group consisting of CrN, TiN, TiAlN, TiAlVN, TiAlVCN, TiSiN, TiSiCN, TiAlSiN and combinations thereof, wherein the second under layer ranges in thickness from 0.1 to 100 μm. 
     
     
         16 . The method of  claim 14 , wherein the second functional layer is diamond-like-carbon (DLC). 
     
     
         17 . The method of  claim 16 , wherein the diamond-like-carbon (DLC) is selected from the group consisting of ta-C, ta-C:H, DLCH, PLCH, GLCH, Si-DLC, N-DLC, O-DLC, B-DLC, Me-DLC, F-DLC and combinations thereof. 
     
     
         18 . The method of  claim 1 , further including from 1 to 100 series of incremental coating layers, wherein each series of incremental coating layers includes a combination of an incremental adhesion promoting layer, an incremental functional layer and an optional incremental under layer, wherein the each series of incremental coating layers is configured as follows:
 (i) wherein the optional incremental under layer is selected from the group consisting of CrN, TiN, TiAlN, TiAlVN, TiAlVCN, TiSiN, TiSiCN, TiAlSiN and combinations thereof; ranges in thickness from 0.1 to 100 μm; and is contiguous with a surface of the functional layer and the incremental adhesion promoting layer: wherein the optional incremental under layer is interposed between the functional layer and the incremental adhesion promoting layer,   (ii) wherein the incremental adhesion promoting layer is selected from the group consisting of Cr, Ti, Si, W, CrC, TiC, SiC, WC, and combinations thereof; ranges in thickness from 0.1 to 50 μm; and is contiguous with a surface of the functional layer or optional incremental under layer, and the incremental functional layer:   wherein the incremental adhesion promoting layer is interposed between the functional layer and the incremental functional layer or between the optional incremental under layer and the incremental functional layer   (iii) wherein the incremental functional layer is selected from the group consisting of a fullerene based composite, graphene, a diamond based material, diamond-like-carbon (DLC), and combinations thereof; ranges from 0.1 to 50 μm in thickness; and is contiguous with a surface of the incremental adhesion promoting layer.   
     
     
         19 . The method of  claim 18 , wherein the incremental functional layer is diamond-like-carbon (DLC). 
     
     
         20 . The method of  claim 19 , wherein the diamond-like-carbon (DLC) is selected from the group consisting of ta-C, ta-C:H, DLCH, PLCH, GLCH, Si-DLC, N-DLC, O-DLC, B-DLC, Me-DLC, F-DLC and combinations thereof. 
     
     
         21 . The method of  claim 18 , wherein the optional incremental under layer hardness ranges from 800 to 3500 VHN. 
     
     
         22 . The method of  claim 18 , wherein the incremental adhesion promoting layer hardness ranges from 200 to 2500 VHN. 
     
     
         23 . The method of  claim 18 , wherein the incremental functional layer hardness ranges from 1000 to 7500 VHN. 
     
     
         24 . The method of  claim 18 , further including a gradient at the interface of the optional incremental under layer and the incremental adhesion promoting layer ranging from 0.01 to 10 μm. 
     
     
         25 . The method of  claim 18 , further including a gradient at the interface of the incremental adhesion promoting layer and the incremental functional layer ranging from 0.01 to 10 μm. 
     
     
         26 . The method of  claim 1 , wherein the surface roughness of the functional layer ranges from 0.01 μm to 1.0 μm Ra. 
     
     
         27 . The method of  claim 18 , wherein the surface roughness of the outermost incremental functional layer ranges from 0.01 μm to 1.0 μm Ra. 
     
     
         28 . The method of  claim 1 , wherein the counterface wear scar depth as measured by the block on ring friction test is less than or equal to 500 μm. 
     
     
         29 . The method of  claim 1 , wherein the abrasion resistance of the low friction coating as measured by the modified ASTM G105 abrasion test yields a wear scar depth and a weight loss at least 5 times lower than a single layer coating of the same functional layer. 
     
     
         30 . The method of  claim 1  wherein the one or more drilling tool components is comprised of a carbon steel material that has hardfacing material applied to at least a portion of the area to be coated. 
     
     
         31 . The method of  claim 1  wherein at least a portion of the one or more drilling tool components is comprised of a carbide matrix material. 
     
     
         32 . The method of  claim 1  wherein at least one cutter or insert is brazed to at least one of the one or more drilling tool components of the drilling tool prior to the cleaning step. 
     
     
         33 . The method of  claim 32  wherein the one or more drilling tool components are cooled during the brazing process. 
     
     
         34 . The method of  claim 1  wherein at least one cutter or insert is brazed to at least one of the one or more drilling tool components of the drilling tool prior to the step of applying the multi-layer low friction coating to said one or more drilling tool components. 
     
     
         35 . The method of  claim 34  wherein the one or more drilling tool components are cooled during the brazing process. 
     
     
         36 . The method of  claim 1  wherein the cleaning step includes a solvent bath. 
     
     
         37 . The method of  claim 1  wherein the cleaning step includes ion etching. 
     
     
         38 . The method of  claim 1  further including a processing step after said preparing step and prior to said cleaning step, wherein said processing step comprises polishing at least a portion of the surface of said drilling tool components to a minimum surface roughness specification of less than 1 μm Ra.