MXPA06004815A - Water-based metalworking fluid - Google Patents

Abstract

A water-based, recyclable metalworking fluid comprises a polyalkylene glycol, an alkanolamine, a polyglycol surfactant, a polyol surfactant, a biocide and a corrosion inhibitor. The biocide may comprise a mixture of biocidal compounds effective against bacterial and fungal organisms. The material may also include an isoalkoxy amine oxide and a glycol ether. The composition may also include ancillary ingredients such as viscosity controlling agents, defoamers, coloring agents and the like. It is a notable feature of the composition of the present invention that it is free of hazardous materials and fatty acids. Also disclosed is a method for using the composition in a metal-shaping operation.

Description

FLUID FOR WATER BASED METAL FIELD OF THE INVENTION This invention relates in general to fluids for metal working. More specifically, the invention relates to fluids for machining water-based recyclable metals, which are free of harmful materials and which are compatible with a wide range of metal alloys.

BACKGROUND OF THE INVENTION Metalworking fluids are used in metal working operations such as, for example, carving, forming, stamping and laminating to provide cooling and lubrication to both the resistance welding part and the metalworking apparatus. Metalworking fluids also work to dispose of oil and debris from the jobsite, and provide corrosion protection for both the strength-bearing part and the metalworking machine. Initially, fluids for metalworking consist of water-based materials or water and oil emulsions. However, the industry has increasingly sought to replace oil-based products with water-based materials. Therefore, the industry is returning to the use of fluids to work metals based on water. In addition to providing a cooling function, the water-based metalworking fluids should provide good lubrication capacity to the piece to be welded by resistance and to the metalworking apparatus, and should be capable of sequestering and removing waste and contaminants, among which are included, oils, from the workplace. In addition, fluids for machining metals based on water should provide good protection against corrosion of both the equipment and the parts to be welded by resistance. For this purpose, the industry has developed various compositions of fluids for machining metals based on water; however, several problems have arisen together with the use of these compositions. Many metal alloys, in particular bronze and steel alloys, include lead in them, and it has been found that this lead can react with the fatty acids in a metalworking fluid to produce a soap and water-insoluble metal deposit that accumulates on the metalworking apparatus. The soap scum attracts and binds to any oils that may be present, thereby making the foam very viscous. The foam is very difficult to remove from the imaginary parts, and may cause the gluing of the metalworking machinery or otherwise interfere with the metalworking process. Therefore, there is a need for a metalworking fluid that is free of fatty acids. It has also been found that various fluids for machining metals based on water include ingredients that are corrosive or otherwise react with copper, lead, zinc and aluminum; therefore, there is an additional need for a metalworking fluid that is not corrosive to a wide variety of metals. Biocontamination is a significant problem in fluids for metal working. This infection can contaminate both the metalworking fluid and the metalworking apparatus, and is the result of the development of bacterial and / or fungal organisms in the fluid. The problem is particularly severe in water-based fluids, and there is a need for a water-based metalworking fluid that is resistant to the development of a broad spectrum of biological species therein. In order to face the various problems discussed above, prior art metalworking fluid compositions often include phenols, cresols, halogenated materials and the like in their formulations. Many of these materials are classified as harmful materials, and their use is severely restricted or limited by law. Therefore, it is further convenient to have a metalworking fluid that does not include any of these harmful materials. As will be described later, the present invention is directed to a water-based metalworking fluid that provides very good lubricity and cooling to the equipment and to the parts to be welded by resistance. The metalworking fluid of the present invention is compatible and non-corrosive with a wide variety of metal alloys. It is free of fatty acids and harmful materials. The metalworking fluid of the present invention is capable of removing oils, dirt and debris from the parts to be welded by resistance and equipment. It is resistant to biological contamination, stable and recyclable.

SUMMARY OF THE INVENTION A recyclable, water-based metalworking fluid is disclosed herein. The fluid comprises an aqueous solution of a polyalkylene glycol, an alkanolane, a polyglycol surfactant, a polyol surfactant, a packet of biocide and a corrosion inhibitor. In specific embodiments, the alkanolamine may comprise one or more of triethanolamine, diethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine and the like. The biocide package may comprise a mixture of biocide materials, this mixture is effective in controlling both the mucus and bacterial contamination. In specific embodiments, the metalworking fluid may also include an isoalkyloxyamine oxide and / or a benzotriazo salt. The compositions of the present invention are capable of being formulated so that they are free of phenolic compounds and / or fatty acids. Methods for using fluids in metal-working processes are also discussed, while spent fluid can be recycled and reused.

DETAILED DESCRIPTION OF THE INVENTION The water-based metalworking fluid of the present invention consists of a mixture of a polyalkylene glycol, which functions as a lubricant together with an alkanolamine, a first surfactant which is a polyglycol, and a second surfactant which It is a polyol. The composition includes a biocide package which may comprise an individual biocidal material or a combination of biocides. The composition also includes a corrosion inhibitor package which may also comprise a single corrosion inhibitor or a mixture of corrosion inhibitors. The above ingredients are mixed in water. The composition can also be provided as a concentrate that is subsequently diluted for use. It has been found that materials of this type provide very good lubricity and cooling in the processes for metal working. In addition, they work very well to sequester and remove contaminants, including oils from the metal-working apparatus and parts to be welded by resistance. The metalworking fluids of the present invention are free of fatty acids that can form deposits. They are also free of harmful material such as, for example, phenols, cresols and the like. The compositions are compatible with a wide variety of metals including ferrous and non-ferrous metals, and it is a remarkable feature of the present invention that they are not corrosive to copper, zinc or lead. In specific embodiments, the metalworking fluid comprises, on a weight basis, 12-14% polyalkylene glycol; 1-15% of the alkanolamine; 5-7% of the polyglycol surfactant; 0.5-1.0% of the polyol surfactant; 10-30% of the corrosion inhibitor; and 0.5-1.0% of the biocide, with the rest being water. In certain embodiments of the above composition, the alkanolamine comprises 13-15% of the composition, and in others, the corrosion inhibitor comprises 8-10% of the composition. It should be noted that throughout this specification, all percentages are given on a weight basis, unless stated otherwise. The polyalkylene glycol functions as the primary lubricant in the compositions. It has been found that these materials are quite lubricious and soluble in water. In addition, they are stable under conditions of high temperature and high pressure that are often found in processes for metal working. The polyalkylene glycol materials are not degraded by contaminating oils and they can be mixed with the metalworking fluid, and the compositions including polyalkylene glycol lubricants can be easily recycled. The most preferred polyalkylene glycols for use in the present invention are the water soluble polyalkylene glycols. One of these materials comprises a polyalkylene glycol sold by the Dow Chemical Corporation under the designation "Ucon EPML-483". Other similar materials include ADDCO MLB 10X sold by the Lubrizol Corporation and Actralube BN 6000 sold by Georgia Pacific. Other similar materials are commercially available and will be readily apparent to those skilled in the art. Typically, materials of this type are supplied as aqueous solutions. The metalworking fluids of the present invention also include an alkanolamine. There are several alkanolamines that can be used either alone or in combination in the present invention. Preferred alkanolamines are in general C 1 -C 4 alkanolamines. The primary, secondary and tertiary alkanolamines can all be employed in the practice of the present invention. A preferred specific alkanolamine comprises triethanolamine (TEA, for its acronym in English). Mono- and di-ethanolamine can also be used. Other alkanolamines include mono-, di- and tri-isopropanolamine. The alkanolamines can be used either alone or in combination, and generally comprise 1-15%, and in certain embodiments 13-15% of the composition. The composition of the present invention preferably includes two surfactants, the first being a polyglycol surfactant and the second being a polyol surfactant. It has been found that this combination of surfactants provides superior sequestering performance and facilitates the removal of oils and other hydrophobic materials from the piece to be welded by resistance and machinery. A polyglycol surfactant useful in the present invention comprises a polyoxypropylene and polyoxyethylene block copolymer. Surfactants of this type are commercially available from various sources, and a material having a particular utility in the present invention comprises the product sold under the designation Pluronic 17R2. This material is available from BASF Corporation. Other of these surfactants that can be used in this invention include P-41-300 sold by the Hoescht Celanese Corporation, and Triton EF-14 sold by Rohm and Haas. Still other materials will be known to those skilled in the art. The polyol surfactant, in one embodiment, comprises a material sold under the designation Superwet 9.5 by the Superior Chemical Corporation of Indianapolis, Indiana. This particular material comprises poly (oxy-1,2-ethanediyl), alpha- (4-nonylphenyl) -omega-hydroxy, branched. Other polyol and polyglycol surfactants may also be employed in the practice of the present invention. Some of these materials include Triton N-101 sold by Rohm and Haas, and Tomadol 9E0 sold by Tomal Products, Inc. of Milton, Wisconsin. While there is a wide variety of compositions that can be implemented in accordance with the present invention, in a preferred embodiment, the polyglycol surfactant is present in a variation of 5-7% and the polyol surfactant in a variation of 0.5-1.0. %. The material of the present invention includes a biocide which, in a preferred embodiment, is a mixture of materials having a biocidal effect against both bacteria and fungi. A preferred mixture comprises a first component which is a morpholine compound. A preferred morpholine biocidal compound comprises 4- (2-nitrobutil) morpholine. Other morpholine materials include 4, 40- (2-ethyl-2-nitrotrimethylene) dimorpholine and methylenedimorpholine. Morpholine biocides are available from Angus Chemical Company of Buffalo Grove, Illinois under the designation Bioban P-1487 and Bioban CS-1135. Materials sold by Rohm and Haas with the Kaython EDC 1.5 designation can also be used for this purpose. Another preferred biocidal material for incorporation into the metalworking fluid of the present invention comprises a product sold under the designation Busan 77 by Buckman Laboratories, Inc. of Memphis, Tennessee. This material comprises poly (oxy-1,2-ethanediyl (dimethylimin) -1,2-ethanediyl (dimethylimin) -1,2-ethanediyl dichloride). The equivalent compositions are sold under the designation Bioban TS by Angus chemical Company, and the aforementioned Kaython EDC 1.5. In specific embodiments of the present invention, a biocidal mixture of 0.35-0.5% of the Bioban P-1487 material and 0.5-1.0% of the Busan 77 material is employed. Other compositional variations of these materials, as well as other combinations of materials, are also useful in the practice of the present invention. The compositions of the present invention will preferably also include a corrosion inhibitor. The specific corrosion inhibitor employed will depend, to some degree, on the nature of the metals with which the material is being used. A class of compounds that have utility as corrosion inhibitors comprises thiazoles, and a specific thiazole material is sodium 2-mercaptobenzothiazole. This material is available from Lubrizol Corporation of Wiffe, Ohio in a formulation sold under the designation Aqualox 236. Other corrosion inhibitors include materials sold by Lubrizol Corporation under the designation Alox. Typically, the corrosion inhibitor will be present in an amount of about 10-30%, and in specific embodiments in a variation of 8-10%. In addition to the foregoing, the metalworking fluids of the present invention may include other active components. A material frequently employed in the compositions of the present invention comprises diethylene glycol monobutyl ether. This material is often referred to in the art as DB glycol ether, and in the compositions of the present invention typically is present in an amount of about 0.5-2%. Other ingredients in the composition of the present invention include isoalkyloxyamine oxide. This material may be present in an amount of about 10-12%. Additional amounts of benzotriazole salts can also be added to the compositions. The metalworking fluids of the present invention may also include secondary ingredients such as, for example, coloring agents, fragrances, viscosity or rheology control agents, defoamers, odors and the like. In view of the teaching presented herein, various compositions of the present invention can be easily implemented by those skilled in the art. A particular composition of the present invention comprises, on a weight basis: Monoisopropanolamine 1-2% Diisopropanolamine 6-6.5% Triisopropanolamine 6.6.5% Isoalkyloxyamine oxide 10.12% 4 (2-nitrobutyl) morpholine at 76-85%; 4.40 (2- 0.35-0.5% ethyl-2-nitrotrimethylene) dimorpholine at 2-7%; Methylendimorpholine 3.9-6.5%; morpholine 3-6%; 1-nitropropane 0.3-5.3% (Biobad P-1487) 2-mercaptobenzothiazole mold inhibitor 8-10% sodium (Aqualox 236) Polyoxypropylene block polymer 5-7% Sodium salt and benzotriazole 1.5-2% Poly (oxy-1, 2-ethanediyl (dimethylimin) -1,2-ethanediyl (dimethylimin) -1,2-ethanediyl) dichloride 0.5-1.0%; polyalkylene glycol (ücon EPML-483) at 12-14%; poly (oxy-l-2-ethanediyl), alpha- (4-nonylphenyl) -omega-hydroxy, branched at 0.5-1.0% It has been found that the above composition works very well as a metalworking fluid to cut or otherwise configure a wide variety of materials including lead bronze. The composition provides a high degree of lubricity, and is compatible with systems for high volume, high speed metal working. The fluid is stable against biological contamination, and does not form metallic soap deposits. It cleans easily and sequesters oils and is not corrosive to bronze. The service life of the material is long, and it can be easily recycled. In this regard, the spent fluid can be collected and filtered to remove impurities and debris. The oils and other contaminants can be removed by distillation and / or filtration, and the resulting fluid is reused in the metalworking process. In some cases, the recycled fluid will have certain of its components filled before being reused. Still other compositions can be implemented in accordance with the teachings presented herein. Modifications of the above composition can be prepared, for example, by adding 1.25-1.75% glycol ether DB to the mixture. Relatively small amounts of an anti-foaming agent can be added to the composition, such as, for example, a polysiloxane defoamer. Typically, defoamers are employed at approximately 0.05-0.25%. Still other compositions can be implemented in accordance with the teachings presented herein. It should be understood that the analysis description and previous examples are illustrative of particular embodiments of the invention and should not be construed as limitations to the practice thereof. What defines the scope of the invention are the following claims, which include all equivalents.

Claims (27)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property: 1. A water-based recyclable metalworking fluid, characterized in that it comprises : Water; a polyalkylene glycol; an alkanolamine; a polyglycol surfactant; a polyol surfactant; a biocide; and a corrosion inhibitor.
2. 2. The metalworking fluid according to claim 1, further characterized in that it includes an isoalkyloxyamine oxide.
3. 3. The metalworking fluid according to claim 1, further characterized in that it includes a benzotriazole salt.
4. 4. The metalworking fluid according to claim 1, characterized in that the alkanolamine comprises a mixture of alkanolamines.
5. The metalworking fluid according to claim 1, characterized in that the alkanolamine is selected from the group consisting of: triethanolamine, diethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, and combinations thereof.
6. 6. The metalworking fluid according to claim 1, characterized in that the biocide comprises a mixture of biocidal materials, the mixture has an antibacterial and antifungal effect.
7. The metalworking fluid according to claim 6, characterized in that the mixture of biocidal materials includes at least one morpholine compound.
8. The metalworking fluid according to claim 6, characterized in that the mixture of biocidal materials includes poly (oxy-1,2-ethanediyl (dimethylimin) -1,2-ethanediyl (dimethylimin) -1,2-ethanediyl dichloride. ).
9. 9. The metalworking fluid according to claim 1, characterized in that it is free of phenols.
10. 10. The metalworking fluid according to claim 1, characterized in that it is free of fatty acids.
11. The metalworking fluid according to claim 1, characterized in that the polyglycol surfactant comprises a polyoxypropylene-polyoxyethylene block copolymer.
12. 12. The metalworking fluid according to claim 1, characterized in that the polyol surfactant comprises poly (oxy-l-2-ethanediyl), branched alpha- (4-nonylphenyl) -omegahydroxy.
13. 13. A water-based recyclable metalworking fluid, characterized in that it comprises, on a weight basis: 12-14% of a polyalkylene glycol; 1-15% of an alkanolamine; 5-7% of a polyglycol surfactant; 0.5-1.0% of a polyol surfactant; 10-30% of a corrosion inhibitor; 0.5-1.0% of a biocide; and the rest, water. 1 .
14. The metalworking fluid according to claim 13, further characterized in that it includes, on a weight basis: 10-12% isoalkyloxyamine oxide.
15. 15. The metalworking fluid according to claim 13, further characterized in that it includes, on a weight basis: 1.5-2% of a benzotriazole salt.
16. 16. The metalworking fluid according to claim 13, characterized in that the biocide comprises a mixture of biocidal materials, and a mixture having antibacterial and antifungal effects.
17. 17. The metalworking fluid according to claim 16, characterized in that the mixture of biocidal materials includes, on a basis by weight, 0.35-0.5% of a morpholine compound.
18. 18. The metalworking fluid according to claim 16, characterized in that the mixture of biocidal materials includes, on a weight basis, 0.5-1.0% poly (oxy-1,2-ethanediyl (dimethylimin) -1 dichloride, 2-ethanediyl (dimethylimin) -1,2-ethanediyl).
19. 19. The metalworking fluid according to claim 13, further characterized in that it includes a material selected from the group consisting of: surfactants, antifoaming agents, coloring agents, fragrances, viscosity control agents, and combinations thereof.
20. 20. The metalworking fluid according to claim 13, characterized in that the alkanolamine component comprises 13-15% of the composition.
21. 21. The metalworking fluid according to claim 13, characterized in that the corrosion inhibitor comprises 8-10% of the composition.
22. 22. A method for molding a piece to be welded by metallic resistance, the method characterized in that it includes the step of: contacting the piece to be welded by resistance with a water-based recyclable metalworking fluid, while the piece to be welded by resistance is being molded, the fluid comprises: a polyalkylene glycol; an alkanolamine; a polyglycol surfactant; a polyol surfactant; a biocide; and a corrosion inhibitor.
23. The method according to claim 22, characterized in that it includes the additional steps of: collecting the exhausted metal working fluid; and recycling the exhausted metalworking fluid.
24. The method according to claim 22, characterized in that the piece to be welded by resistance comprises leaded bronze, and wherein the method for molding comprises cutting the piece to be welded by resistance of leaded bronze.
25. The method according to claim 22, characterized in that the fluid comprises, on a weight basis: 12-14% of the polyalkylene glycol; 1-15% of the alkanolamine; 5-7% of the polyglycol surfactant; 0.5-1.0% of the polyol surfactant; 10-30% of the corrosion inhibitor; 0.5-1.0% of the biocide; and the rest water.
26. 26. The method according to claim 25, characterized in that the metalworking fluid further includes, on a weight basis, 10-12% isoalkyloxyamine oxide.
27. 27. The method according to claim 25, characterized in that the metalworking fluid further includes, on a weight basis, 1.5-2% of a benzotriazole salt.