GB1573456A

GB1573456A - High production rate cutting fluid and coolant

Info

Publication number: GB1573456A
Application number: GB48753/76A
Authority: GB
Original assignee: Standard Oil Co
Current assignee: Standard Oil Co
Priority date: 1975-12-05
Filing date: 1976-11-23
Publication date: 1980-08-20
Also published as: FR2333854B1; BE848640A; NL7613515A; DE2654217A1; IT1064327B; FR2333854A1; JPS5269081A

Description

(54) HIGH PRODUCTION RATE CUTTING FLUID AND COOLANT (71) We, THE STANDARD OIL COMPANY, a corporation organised under the laws of the State of Ohio, United States of America of Midland Building, Cleveland, Ohio 44115, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a composition of matter adapted for use both as a coolant and a lubricating agent in metal cutting, and more particularly pertains to a composition which is used in a superior cutting and cooling fluid which is based on nonpetroleum oil and is a water-in-oil emulsion which is capable of sustaining high production rates for long periods of time.

In the machining of metals in operations such as cutting, threading, tapping, grinding, honing, lapping, milling, and the like, it is customary to flood the tool and work with a coolant to carry away heat from the tool and work, and normally such coolants are also so compounded as to lubricate the operation. Because of the high unit pressures involved, particularly in highspeed operations, the cutting fluid, if used also as a lubricant, must be an exceptionally capable lubricant. Many of such previously known fluids are petroleum oil-based fluids which are oil-in-water emulsions. The present invention relates to non-petroleumbased cutting fluids.

It is an object of this invention to provide a composition for use in a novel cutting and cooling fluid in the form of a water-in-oil emulsion, the composition being capable of being used either as formed or in dilute form, preferably as formed, which will be effective as a coolant and lubricant under the conditions noted. Another object is to provide a composition which gives excellent lubrication and cooling in a single fluid through use of water-in-oil emulsions which lubricate by virtue of an external oil phase and cool by heat capacity and by virtue of the heat of vaporization of water. Another object is to provide a stable, non-corrosive, rust-inhibiting, metal-processing lubricant and coolant which has exceptionally long use life and can be degreased with water instead of conventional solvents. The cutting fluid embodied herein has been found to have an emollient effect on the hands of workers exposed to it.

The design of modern metal-cutting machines often requires that the lubricant be the coolant. In the present invention, the water is present in an invert emulsion which means that the oil is the external phase to wet the metal surfaces and the cutting fluid provides lubrication superior to that of other emulsions. This overcomes the most common complaint of poor lubrication for soluble cutting fluid.

When approaching the problem of providing an efficient and long-lasting lubricant-coolant, it must be remembered that the efficiency of a coolant is dependent upon its specific heat, i.e., the amount of heat energy required to raise the temperature of a unit weight of the material one degree at temperatures below the vaporization temperature and in some cases its heat of vaporization. While oils are known to be good lubricants, they generally are poor coolants as compared to water because the specific heat of mineral oil, for example, is only about 0.5 that of water. On the other hand, it is well known that except under special conditions, water is not a good lubricant. In the instant case, the fluid does not cool alone because of the specific heat of the water it contains; it provides superior cooling because the water is converted to steam, absorbing heat due to vaporization of the liquid. It is thus required to add makeup water to the fluid as it is being used in the cutting operation by means well known.

The compositions of this invention provide maximum lubrication properties and at the same time act as efficieni coolants. The compositions of this invention maintain stability under ambient and operating conditions over a considerable range of water content and working conditions. The compositions of this invention readily re-emulsify water which is added as makeup for that lost by vaporization during the coolant function.

This invention therefore provides a composition for use as a water-in-oil emulsion metal cutting fluid, or for use in the preparation of a water-in-oil emulsion metal cutting fluid, comprising Parts by weight Ingredient Broad Preferred low-viscosity inactive or active (as hereinafter defined) sulfurized ester of an olefinic fatty acid 15-84 22-48 rosin acid soap 010 3-6 ethoxylated castor oil 8-25 10-20 amide of diethanol amine and a fatty acid 8-25 1020 biocide-fungicide 08 .1-5 chlorinated fat or fatty acid ester 015 2-10 amine-type rust inhibitor 010 07 Na NO2 5 0.3.5 foam inhibitor e3 02 Water (distilled or deionized) e60 8.30 The combination of ethoxylated castor oil and a fatty amide of diethanol amine constitutes an efficient emulsifier system when used in conjunction with an oily material of a specific type. Auxiliary conventional emulsifiers such as rosin acid salts and sodium petroleum sulfonate can be used as adjuncts, but are not essential. The oily material forming the external phase of the compositions of this invention preferably comprises chemicals providing active species (S, Cl) known to be effective lubricating agents in metal cutting, for example sulfurized esters chlorinated paraffins. Preferred are those oily materials of the foregoing types which are of relatively low viscosity (3W1000 SSU at 100"F).

By the terms active sulfur and active chlorine are meant sulfur and chlorine which form iron sulfide or chloride during the metal-working operation, thereby dirtying the bearing surfaces and hence preventing welding of the bearing surfaces.

The compositions of this invention can also contain the usual anti-rust agents, biocides, foam inhibitors, and the like.

In the following examples which will further illustrate this invention, the amounts of ingredients are expressed in parts by weight unless otherwise indicated.

Example 1 A cutting oil containing inactive sulfur and chlorine was prepared using the following ingredients: Ingredient Parts low-viscosity active sulfurized ester of an olefinic fatty acid 20 low-viscosity synthetic fatty acid ester 27 ethoxylated castor oil 13 amide of diethanol amine and coconut fatty acid- 13 chlorinated synthetic fatty acid ester (28-300A Cl) blow to 300 SUS at 100"F 5 Na NO2 1.5 water (deionized) 20.5 Example 2 A cutting oil was prepared using the following ingredients: Ingredient Parts low-viscosity inactive sulfurized fat 39.65 ethoxylated castor oil 16 amide of diethanol amine and coconut acid 16 morpholine biocide-fungicide 0.15 chlorinated methyl stearate (20 /" C1) 7.5 Na NO2 - 0.2 water (deionized) 20.5 Example 3 An active-sulfur cutting oil was prepared using the following ingredients: Ingredient Parts highly sulfurized ester of an olefinic fatty acid 25.91 rosin acid 4 KOM 0.22 neutralized, esterified ethoxylated castor oil 13 ethoxylated castor oil 4 amide of diethanol amine and coconut acid 13 morpholine-type biocide fungicide 3.87 chlorinated methyl stearate 7.5 triethanol amine 7 Na NO2 water (demineralized) 20.5 The neutralized, esterified ethoxylated castor oil is an ethoxylated castor oil which is treated with an alcohol and then a base to react all free carboxyl groups that may be present in the composition of this Example, the total ethoxylated castor oil content is 17 parts.

Example 4 A petroleum oil-based cutting oil which is outside the scope of the present invention but included for comparison purposes was prepared from the following ingredients: Ingredient Parts 100-sec. naphthenic oil 81.84 500-sec. naphthenic oil - 9.09 sulfur 0.9 sulfurized terpene 1.72 sulfurized lard oil, viscous 4 chlorinated wax (65V Cl) 0.45 polyisobutylene 2 Example 5 Another petroleum oil-based cutting oil outside the scope of this invention which could be emulsified to a water-in-oil emulsion otherwise similar to that described in Example 1 was prepared from the following ingredients: Ingredient Parts 100-sec. paraffinic neutral oil 31.44 highly sulfurized olefinic fatty acid ester 9.65 sulfur 0.19 sulfurized terpene 2.70 chlorinated paraffin 0.43 sodium petroleum sulfonate emulsifier 15.44 ethoxylated castor oil 5.79 amide of diethanol amine and coconut acid 9.65 rosin acid 3 KOH 0.47 Na NO2 1.45 water (deionized) 19.79 Example 6 The various cutting oils described in the preceding examples were evaluated on a test-cutting machine which was a 1 and 1/4inch, 6-spindle New Britain Model 52 automatic screw machine which was used to manufacture an ASTM part from l-inch bar stock. The test conditions of machine operation were adjusted so as to cause tool failure within a 6- to 8-hour period (normal working time during one shift). Tool failure is caused bv the occurrence of one or more of three: (1) oversize cut part caused by excessive tool wear, (2) undersize cut part caused by welding of metal onto the tool cutting edge, and (3) finish failure on the part. This is excessive roughness on the surface of the part.

For each cutting oil, the tool feed and spindle speed of the machine were adjusted to give from 6 to 8 hours of continuous operation before tool failure occurred. The production rate was then determined.

Adjustments were made in feed and speed so as to give the highest possible rate of production of parts within the 6- to 8-hour period for a given cutting oil. The production rate is expressed in parts per hour or, more preferably, in seconds per part under maximum production conditions as described above.

The cutting oils were found to have the following maximum cutting rates: Cutting Oil Seconds Per Part Example 1 Less than 11.8, more than 8.8.

Example 2 Less than 11.8.

Example 3 Less than 11.8.

Example 4 More than 19.5.

Example 5 Less than 13.7, more then 11.8.

WHAT WE CLAIM IS: 1. A composition for use as a water-in-oil emulsion metal-cutting fluid or for use in the preparation of a water-in-oil emulsion metal cutting fluid, comprising Ingredient Parts by weight low-viscosity inactive or active (as herein defined) sulfurized ester of an olefinic fatty acid 15-84 rosin acid 0--10 ethoxylated castor oil 8-25 amide of diethanol amine and a fatty acid 8-25 biocide-fungicide 0-8 chlorinated fat or fatty acid ester e15 Na NO2 foam inhibitor water (distilled or deionized) W60 2. A composition as claimed in claim 1 in which the low-viscosity sulfurized ester of the olefinic fatty acid is present in from 22 to 48 parts by weight.

3. A composition as claimed in claim 1 or claim 2 in which the rosin acid is present in from 3 to 6 parts by weight.

4. A composition as claimed in any of claims 1 to 3 in which the ethoxylated castor oil is present in from 10 to 20 parts by weight.

5. A composition as claimed in any of claims 1 to 4 in which the amide of diethanolamine and fatty acid is present in from 10 to 20 parts by weight.

6. A composition as claimed in any of claims 1 to 5 in which the water is present in from 8 to 30 parts by weight.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

The neutralized, esterified ethoxylated castor oil is an ethoxylated castor oil which is treated with an alcohol and then a base to react all free carboxyl groups that may be present in the composition of this Example, the total ethoxylated castor oil content is 17 parts.

Example 4 A petroleum oil-based cutting oil which is outside the scope of the present invention but included for comparison purposes was prepared from the following ingredients: Ingredient Parts

100-sec. naphthenic oil 81.84 500-sec. naphthenic oil - 9.09 sulfur 0.9 sulfurized terpene 1.72 sulfurized lard oil, viscous 4 chlorinated wax (65V Cl) 0.45 polyisobutylene
2 Example 5 Another petroleum oil-based cutting oil outside the scope of this invention which could be emulsified to a water-in-oil emulsion otherwise similar to that described in Example 1 was prepared from the following ingredients: Ingredient Parts

100-sec. paraffinic neutral oil 31.44 highly sulfurized olefinic fatty acid ester 9.65 sulfur 0.19 sulfurized terpene 2.70 chlorinated paraffin 0.43 sodium petroleum sulfonate emulsifier 15.44 ethoxylated castor oil 5.79 amide of diethanol amine and coconut acid 9.65 rosin acid 3 KOH 0.47 Na NO2 1.45 water (deionized) 19.79 Example 6 The various cutting oils described in the preceding examples were evaluated on a test-cutting machine which was a 1 and 1/4inch, 6-spindle New Britain Model 52 automatic screw machine which was used to manufacture an ASTM part from l-inch bar stock. The test conditions of machine operation were adjusted so as to cause tool failure within a 6- to 8-hour period (normal working time during one shift). Tool failure is caused bv the occurrence of one or more of three: (1) oversize cut part caused by excessive tool wear, (2) undersize cut part caused by welding of metal onto the tool cutting edge, and (3) finish failure on the part. This is excessive roughness on the surface of the part.

For each cutting oil, the tool feed and spindle speed of the machine were adjusted to give from 6 to 8 hours of continuous operation before tool failure occurred. The production rate was then determined.

Adjustments were made in feed and speed so as to give the highest possible rate of production of parts within the 6- to 8-hour period for a given cutting oil. The production rate is expressed in parts per hour or, more preferably, in seconds per part under maximum production conditions as described above.

The cutting oils were found to have the following maximum cutting rates: Cutting Oil Seconds Per Part Example 1 Less than 11.8, more than 8.8.

Example 2 Less than 11.8.

Example 3 Less than 11.8.

Example 4 More than 19.5.

Example 5 Less than 13.7, more then 11.8.

WHAT WE CLAIM IS: 1. A composition for use as a water-in-oil emulsion metal-cutting fluid or for use in the preparation of a water-in-oil emulsion metal cutting fluid, comprising Ingredient Parts by weight low-viscosity inactive or active (as herein defined) sulfurized ester of an olefinic fatty acid 15-84 rosin acid 0--10 ethoxylated castor oil 8-25 amide of diethanol amine and a fatty acid 8-25 biocide-fungicide 0-8 chlorinated fat or fatty acid ester e15 Na NO2 foam inhibitor water (distilled or deionized) W60 2. A composition as claimed in claim 1 in which the low-viscosity sulfurized ester of the olefinic fatty acid is present in from 22 to 48 parts by weight.
3. A composition as claimed in claim 1 or claim 2 in which the rosin acid is present in from 3 to 6 parts by weight.
4. A composition as claimed in any of claims 1 to 3 in which the ethoxylated castor oil is present in from 10 to 20 parts by weight.
5. A composition as claimed in any of claims 1 to 4 in which the amide of diethanolamine and fatty acid is present in from 10 to 20 parts by weight.
6. A composition as claimed in any of claims 1 to 5 in which the water is present in from 8 to 30 parts by weight.
7. A composition as claimed in any of

claims 1 to 6 in which the chlorinated fat or fatty acid ester is present in from 2 to 10 parts by weight.
8. A composition as claimed in any of claims 1 to 7 in which the biocide-fungicide is present in from 0.1 to 5 parts by weight.
9. A composition as claimed in claim 1 -substantially as herein described with reference to the Examples.
10. A process of cutting metals wherein a metal-cutting fluid acting as a coolant and lubricant is utilized, in which said fluid is as claimed in any of claims 1 to 9.