Metalworking fluid composition and method for its use in the machining of compacted graphite iron

Abstract

Compositions and methods for reducing toolwear during iron-machining, including applying a composition comprising water; a lubricant ester; and a sulfur-containing lubricant additive.

What is claimed is: 
     
         1 . An iron-machining composition comprising
 (a) water;   (b) a sulfur-containing lubricant additive; and   (c) optionally containing a lubricant ester in an amount of about 0 wt % to about 50 wt % of the iron-machining composition.   
     
     
         2 . The composition of  claim 1 , wherein the lubricant ester comprises about 0.05 wt % to about 50 wt % of the iron-machining composition. 
     
     
         3 . The composition of  claim 1 , wherein the lubricant ester comprises a polyol ester selected from those of C 12  toC 18  fatty acid esters of 2,2 dimethyl-1,3-propanediol, 2-propanol, 1,1,1, tris(hydroxymethyl)propane, 2-hydroxy-1,3-propanediol, 2,2-bis(hydroxymethyl)-1,3-propanediol, and 1,2,3-propanetriol. 
     
     
         4 . The composition of  claim 1 , wherein the lubricant ester comprises a glycerol-based ester. 
     
     
         5 . The composition of  claim 4 , wherein the lubricant ester comprises a glycerol ester of C 12  to C 18  saturated and unsaturated fatty acids. 
     
     
         6 . The composition of  claim 5 , wherein the ester is derived from vegetable oils and animal fats. 
     
     
         7 . The composition of  claim 5 , wherein the ester is synthetically produced via the reaction of fatty acids with glycerol. 
     
     
         8 . The composition of  claim 1 , wherein the lubricant ester comprises a polyol ester produced by the initial reaction of the polyol with ethylene oxide and/or propylene oxide followed by subsequent esterification, to yield a polyoxyalkylated polyol ester. 
     
     
         9 . The composition of  claim 1 , wherein the lubricant ester comprises a oligomeric or polymeric ester produced by the condensation of hydroxyl-functionalized fatty acids, such as ricinoleic acid. 
     
     
         10 . The composition of  claim 1 , wherein the lubricant ester comprises C 18  fatty acid esters of 2,2 dimethyl-1,3-propanediol, 2-propanol, 1,1,1, tris(hydroxymethyl)propane, 2-hydroxy-1,3-propanediol, 2,2-bis(hydroxymethyl)-1,3-propanedioI, 1,2,3-propanetriol, or combinations thereof. 
     
     
         11 . The composition of  claim 1 , wherein the lubricant ester is present in an amount of less than about 50 wt % of the iron-machining composition. 
     
     
         12 . The composition of  claim 1  wherein the sulfur-containing lubricant additive is selected from the group consisting of sulfurized alpha olefins, di-branched alkyl tri and polysulfides, sulfur containing carboxylic acids, complex sulfurized esters, and/or dialkyl polysufides. 
     
     
         13 . The composition of  claim 1 , wherein the sulfur-containing lubricant additive comprises a dialkyl polysufide selected from those having a formula:
   CH 3 —C(R 1 )(R 2 )—(CH 2 )n-) x -S m  
   whereby R 1 ═H or CH 3 , R 2 ═H or CH 3 , n=8-20, x=1-2, and m=2-7.   
     
     
         14 . The composition of  claim 1 , wherein the sulfur-containing lubricant additive is present in an amount of about 0.5 wt % to about 7 wt %. 
     
     
         15 . The composition of  claim 1 , further comprising fatty acids selected from those containing saturated and unsaturated chains of between 12 and 22 carbons, in an amount of about 0 wt % to about 12 wt %. 
     
     
         16 . The composition of  claim 1 , further comprising about 3 wt % to about 15 wt % of a mixture of amine compounds having a formula R 1 (R 2 )—N—R, whereby R 1 ═H, CH 3  or —CH 2 CH 2 OH, R 2 ═H, CH3-(CH2) n , whereby n=0-22, —CH 2 CH 2 OH, or cyclic C 6 H 11 , and R 3 ═—(CH 2 CH 2 O) m —H whereby m=1-12, CH 3 —(CH 2 ) x O— whereby x=0-8, or cyclic C 6 H 11 . 
     
     
         17 . The composition of  claim 16 , wherein the amine comprises ethanolamine, triethanolamine, 2-amino-2-methyl propanol, dicyclohexylamine, diglycolamine, or combinations thereof. 
     
     
         18 . The composition of  claim 1 , further comprising about 0 wt % to about 15 wt % of an amine-boric acid comprising alkanolamine borate esters, amine polyborate, amine salts of boric acid, and combinations thereof. 
     
     
         19 . The composition of  claim 1 , further comprising about 0 wt % to about 40 wt % of a mineral oil, the mineral oil comprising a paraffinic oil, naphthenic oil, or mixtures thereof, with an ambient pressure viscosity of between about 15 cSt and about 30 cSt at 40 degrees centigrade. 
     
     
         20 . The composition of  claim 1 , further comprising about 4 wt % to about 10 wt % of a mixture of nonionic and anionic emulsifiers. 
     
     
         21 . A method of machining iron, comprising applying the fluid composition of  claim 1  to the iron during machining. 
     
     
         22 . A method of machining iron, comprising applying the fluid composition of  claim 1  in the form of a water dilution, to the iron during machining. 
     
     
         23 . A method according to  claim 22 , whereby the fluid composition of  claim 1  is diluted in water to a concentration of between 2% by wt. to 50% by weight prior to use in machining of iron. 
     
     
         24 . A method according to  claim 22 , whereby the fluid composition of  claim 1  is diluted in water to a concentration of between 2% by wt. to 15% by weight prior to use in machining of iron 
     
     
         25 . A method of reducing tool wear during machining of iron, comprising applying the fluid composition of  claim 1  at to the iron during machining. 
     
     
         26 . A method of  claim 25  wherein reduced tool wear during machining of iron is achieved by use of the fluid composition diluted in water to a concentration of between 2% by wt to 50% by wt. 
     
     
         27 . A method of  claim 25  wherein reduced tool wear during machining of iron, is achieved by use of the fluid composition diluted in water to a concentration of between 2% by wt to 15% by wt. 
     
     
         28 . The method of  claim 25 , wherein the tool wear is reduced by about 5% to about 90% as compared to conventional lubricant fluids. 
     
     
         29 . The method of  claim 21 , wherein the iron comprises compacted graphite iron.