US 3929652 A
A dual purpose cutting oil is provided which serves as a heavy duty cutting oil and a machine lubricant. The oil comprises a base oil, an extreme pressure agent comprising primarily Bis ( beta -chlorophenethyl) disulfide and a copper corrosion inhibitor comprising an alkyl derivative of 2,5-di-mercapto 1, 3,4-thiadiazole.
Claims available in
Description (OCR text may contain errors)
United States Patent Seni et al.
[ Dec. 30, 1975 DUAL PURPOSE CUTTING OIL Inventors: Leonard S. Seni, Port Arthur, Tex.;
James E. Davis, Summerville, SC; Henry R. Harrison, River Rouge,
Assignee: Texaco Inc., New York, NY.
Filed: Nov. 13, 1974 Appl. No.: 523,301
U.S. Cl. 252/46.7; 72/42; 252/47; 252/475; 252/394 Int. Cl.". C10M l/48;C1OM 3/42; ClOM 5/24; ClOM 7/46 Field of Search 72/42; 252/46.7, 47, 47.5, 252/394 References Cited UNITED STATES PATENTS 8/1969 Rul 252/46.7
6/1974 Malec ..252/46.7 12/1974 Wilpers 252/475 Primary Examiner-Delbert E. Gantz Assistant Examiner-1. Vaughn Attorney, Agent, or Firm-Thomas H. Whaley; Carl G. Ries; Kenneth R. Priem  ABSTRACT A dual purpose cutting oil is provided which serves as a heavy duty cutting oil and a machine lubricant. The oil comprises a base oil, an extreme pressure agent comprising primarily Bis (,B-chlorophenethyl) disulfide and a copper corrosion inhibitor comprising an alkyl derivative of 2,5-di-mercapto 1, 3,4-thiadiazole.
10 Claims, No Drawings DUAL PURPOSE CUTTING OIL BACKGROUND OF THE INVENTION 1. Field of the Invention The invention pertains to the field of cutting oils.
2. Description of the Prior Art Metal cutting and grinding have as their objective a progressive removal of metal from the work piece in the form of chips rather than by plastic reforming of the metal. In the field of metal cutting, the use of single and multiple point tools is well known and a great deal of metal working lubricant is used in the metal cutting process. In general, two types of lubricants are needed: a metal cutting lubricant and a machine oil. The cutting oil serves to remove heat generated during machining of the metal and lubricates the cutting tool against the work and chips. The machine oil lubricates the machine parts.
Cutting oils are generally paraffinic or intermediate base mineral oils. These are preferred because such products generally create less fog or smoke than naphthene oil. In severe conditions, which are more normal than not in heavy duty operations, it may be necessary to use an additive package in the cutting oil. These additives will comprise extreme pressure additives,
copper corrosion inhibitors, oxidation inhibitors, antimist agents, odorants to mask or remove the odors of other additives and other additives for special situations.
It is desirable when considering cutting oils and machine lubricants to think in terms of using one oil for both purposes. The use of a single oil rather than two or more has many advantages including reduced lubricant stock inventory and removal of the effects of cross-contamination of cutting oil and machine lubricant. Although dual purpose cutting oil formulations have been used in automatic screw machines for several years, these formulations often cannot be used in heavy duty cutting operations. Conversely, it is known that heavy duty cutting oil cannot normally be used as machine lubricants since in general they are unsatisfactory in copper corrosion characteristics.
It is an object of our invention to provide a dual purpose cutting oil which may be used for both a cutting oil and a machine lubricant. Because of a unique combination of additives, the oil of our invention will successfully operate as a dual purpose cutting oil for use in heavy duty cutting operations.
SUMMARY OF THE INVENTION The invention is a lubricant which is useful as both a cutting oil and a machine lubricant which comprises a major amount of a base oil and minor amounts of Bis (B-chlorophenethyl) disulfide and minor amounts of an alkyl derivative of 2,5 di-mercapto-l,3,4-thiadiazole.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The dual purpose oil of our invention is comprised of a base oil and additive package. The unique combination of additives in our oil was arrived at after many failures of so called equivalent additives in other combinations. Although each component additive in our oil is used for a purpose for which it is generally known, the unique feature of our invention is the combination of additives which function collectively to give a single product, all the performance properties hereinafter enumerated without undesirable side effects such as malodor, corrosiveness, or instability. It was found in developing our invention that it was not enough to put together a list of additives wherein each was known in the art to impart a specific property. In every combination but the one of our invention, the additives were not compatible with each other and/or the base oil. Thus, other combinations attempted failed even though the additive package consisted of additives known in the art. The unsuccessful formulations showed that when use together, many additives interact with each other unpredictably or tended to ruin the properties of the oil in some way.
BASE OIL The bulk of our oil consists of a base oil.
In fact, usually more of our oil consists of a base oil which may be paraffinic oil of from about to 170 SUS/100F viscosity and preferably to SUS/100F viscosity. It is also acceptable to use a combination of two or more oils as a base oil wherein one oil may range from about 80 to 120, and preferably from about 85 to 105 SUS/l00F viscosity and the other oil may range from to 220 and preferably from about to SUS/100F viscosity. Paraffinic or intermediate base mineral oils are generally preferred as a base oil in our invention since they generate less fog and smoke than a naphthene oil. However, any suitable base oil may be used.
An extreme pressure agent is needed in the dual purpose cutting oil of our invention. The extreme pressure additives useful in our invention are halogenated aryl sulfides. These additives are, particularly, haloaryl polysulfides having one or more halogenated aromatic rings,which if desired can carry side chains containing halogen and/or other substituents.
According to a preferred embodiment of our invention, the extreme pressure additives are chlorophenyl polysulfides. A particularly preferred extreme pressure agent comprises primarily Bis (Ii-chlorophenyl) disulfide which is the reaction product of styrene and sulfur monochloride. This additive is present in amounts ranging from about 0.5 to 10 weight percent and preferably from about 1.0 to 5.0 weight percent of the total oil.
A copper corrosion inhibitor is needed for the oil of our invention. The corrosion inhibitor which is useful for our invention is an alkyl derivative of 2,5di-mercapto-1,3,4-thiadiazole. This copper corrosion inhibitor should be present in amounts ranging from about 0.05 to 5.0 weight percent and preferably from about 0.05 to 0.5 weight percent in the oil of our invention. A particularly preferred copper corrosion inhibitor is described in U.S. Pat. Nos. 2,714,125; 2,714,126 and 2,983,716.
Although the base oil and the two additives mentioned above will provide an acceptable dual purpose cutting oil, it is preferred that other additives be used to provide additional properties which enhance the desirability of the dual purpose cutting oil. It is particularly preferred that a rust inhibitor be used. It is particularly preferred for our invention that a combination of the extreme pressure agent and a copper corrosion inhibitor above be combined with a rust inhibitor comprising a mixture of alkylmaleic acid, phenol and lauryl acid phosphate. This three component additive system provides a particularly preferred cutting oil.
The alkylmaleic acid should be present in amounts ranging from about 0.01 to 1.0 weight percent and preferably from about 0.02 and 0.05 weight percent. The lauryl acid phosphate should be present in amounts ranging from about 0.001 to 0.01 weight percent and preferably from about 0.002 to 0.005 weight percent. The phenol should be present in amounts ranging from trace amounts to about 0.01 weight percent. The percentage of these components is only approximate and may be varied outside of the suggested ranges wihtout departing from the scope of our invention.
It is also desirable that cutting oils have an oxidation inhibitor, an anti-mist additive, and an odorant. The oxidation inhibitor may be selected from those known in the art. A great many oxidation inhibitors are available commercially on many are hindered phenols although other types may be acceptable. Several of these might work in the cutting oil and the dual purpose cutting oil of our invention. However, it is preferred that tertiary butyl phenol or 4-methyl-2,5-ditertiary butyl phenol may be used in amounts ranging from about 0.05 to 1.0 weight percent and preferably 0.1 to 0.5 weight percent.
An anti-mist additive is generally desirable and a few are known in the art. However, it is preferred in the cutting oil of our invention that a copolymer of ethylene and propylene be used.
A particular preferred copolymer of ethylene and propylene has a molecular weight ranging from about 70,000 to 100,000 and a propylene content of from about 35 to 50 percent. This copolymer is usually used diluted with a paraffinic mineral oil. About 0.1 to 10.0 arid preferably about 0.5 to 5.0 weight percent of an anti-mist additive is desirable.
The odorant in the oil of our invention may be any of those that are available in the commercial market. Generally, the choice of an odorant is important in that a specific odorant will normally mask only a few types important. In the oil of our invention, it was found that oil of citronella has performed adequately, although other odorants could have been used.
EXPERIMENTAL Table I following gives three formulations of our invention which have acceptable performance properties as listed. Table II, following, is an illustration of the problems encountered in putting together the formulation of our invention. We found that it was not enough simply to put together an additive package wherein each additive was known in the art to impart a specific property. The additives must be compatible with each other and the base oil, they must compliment each other and function together to give all the properties desired in the intended application. Table ll,'following, shows a comparison of an oil of our invention (A) and three unsuccessful oils, B, C and D. The oils A, B, C and D all contain an additive package of ingredients known in the art to impart qualities which added together should result in a satisfactory dual purpose cutting oil. Yet only A was satisfactory in all respects.
As indicated in Table II, oil B which contains sulfur and chlorine extreme pressure agents with zinc dialkyl dithiophosphate copper corrosion inhibitor had the desired performance characteristic but developed an unacceptable haziness in storage.
Oil C contained a non-corrosive extreme pressure additive and did not require a copper corrosion inhibitor. However, the odor of Oil B was considered objectionable to customers and could not be marketed. All attempts to mask the offensive odor failed.
Oil D was an attempt to develop a suitable product without malodorous or corrosive sulfurized extreme pressure additives. A high extreme pressure level was achieved by using a relatively high concentration of a chlorinated extreme pressure additive. Oil C appeared satisfactory in laboratory tests but gave unsatisfactory maching performance in shop test. Oil A proved satisof odor and thus the selection of an odorant becomes 40 factory in every respect.
TABLE I TEST DATA ON EXPERIMENTAL DUAL PURPOSE CUTTING OIL FORMULATIONS Identification Experimental Dual Purpose Cutting Oil TL-9297 Alternate Alternate Batch No., PARL-RL-73 8214 8619 8904 Composition Base Oil, Vol.
Code 481 101 Pale Oil 50.15 50.15 50.15 Code 409 E Pale Oil 49.85 49.85 49.85 Totals 100.00 100.00 100.00
Finished Oil, Wt.
Base Oil 95.017 95.017 94.917 Car-A-Van 20/20 2.500 2.500 2.500 Amoco (PMS-05440) 0.100 0.100 0.100 TLA-S 10 Code 7566 TLA-5l0 A 2.000 2.000 Code 2001 Anti-Rust Concentrate 0.033 0.033 0.033 MDBP (PMS-05149) 0.300 0.300 Tertiary Butylphenol (PMS-05392) 0.400 Oil of Citronella (PMS-05297) 0.050 0.050 0.050 Totals 100.000 100.000 100.000
Tests Gravity, API 27.8 27.3 27.5 Flash, COC, F 375 375 380 Viscosity, SUS at 100F 158 159 156 Viscosity, SUS at 210F 43.9 43.8 Viscosity Index 102 104 Color, D-1500 L1.0 L1.5 1.1.5
TABLE I-continued TEST' DATA'ON EXPERIMENTAL DUAL PURPOSE 4-Ball Wear, 1 hr.
600 rpm, 75C, scar, mm
40 kg 0.66 0.70 0.64 Load Wear Index, Kg,
D-2596 81.3 91.8 87.1 Weld 501+ 631 631 SAE, lbs, ST-205,
500 rpm 452 442 435 1000 rpm 302 270 275 Mist Test (Modified Woodward Air Release) Original Oil Very Good Very Good Very Good After shearing 10 cycles FISST MS-103 Good" Good Good Sulfur/chlorine EP additive marketed by Cincinnati Milacron Chemicals, Inc. Very Good none to barely perceptible mist or fog. "Good very slight mist or fog.
TABLE II COMPARISON OF EXPERIMENTAL CUTTING OILS AGAINST DUAL PURPOSE OIL REQUIREMENTS Identification A B C D Composition, Wt.
Base Oil 95.02 94.53 95.50 89.67 EP Agent Bis (B-Chlorophenethyl) disulfide 2.50
Sulfurized Di-isobutylene 2.14
Chlorinated Paraffin 2.00 2.00 10.00
Elco 217 Sulfurized EP Agent 2.50 Copper Corrosion Inhibitor Zinc Dialkyl Dithiophosphate 1.33
Amoco 150 Alkyl derivative of 2,5-
di-mercapto- 1 ,3 ,4-thiadiazole 0. l 0
Copolymer of Ethylene and Propylene 2.00 Oxidation Inhibitor 4-methy1-2,6-Ditertiary butyl phenol 0.30 0.30 Rust Inhibitor Alkylmaleic acid, phenol and lauryl acid phosphate 0.03 0.03
Odorant Oil of Citronella 0.05 Quality Characteristics (1) (2) (l) (l) Odor (Acceptable?) Yes Yes No Yes Stability (Stable?) Yes No Yes Yes Copper Corrosion, ASTM D-1306hr. at 160F 1A 1A 1A 1A EP Properties SAE Test, ST-205, LBS. at
500 rpm 452 480 417 500 1000 rpm 302 325 257 345 Load Wear Index. Kg 81.3 51.5 59.0 47.2 Machining Perfonnance Level High High High Low Shop Test Pass Pass Pass Failed We claim: 3. A lubricant as in claim 2 wherein the chlorophenyl l. A lubricant comprising polysulfide is present in an amount ranging from 1.0 to
a. a major amount of a base oil, 5.0 weight percent of the oil and the mercaptob. a minor amount of a chlorophenyl polysulfide and thiadiazole is present in an amount ranging from about c. a minor amount of a mercapto-thiadiazole. 0.05 to 0.5 weight percent.
2. A lubricant as in claim 1 wherein the chlorophenyl 4. A lubricant as in claim 1 wherein the base oil 15 a polysulfide is present in an amount ranging from 0.5 to paraffinic oil having from about to SUS/100F 10 weight percent of the oil and the mercaptoviscosity. thiadiazole is present in an amount ranging from about 5. A lubricant comprising:
0.05 to 5.0 weight percent. a a. a major amount of a base oil,
b. a minor amount of Bis (B-chlorophenethyl) disulfide, and
c. a minor amount of 2,5-di-mercapto-l,3,4-
6. A lubricant as in claim wherein the Bis (B- chlorophenethyl) disulfide is present in an amount ranging from 0.5 to weight percent of the oil and the 2,5-di-mercapto-l,3,4-thiadiazole is present in an amount ranging from about 0.05 to 5.0 weight percent.
7. A lubricant as in claim 5 wherein the Bis (B- chlorophenethyl) disulfide is present in an amount ranging from 1.0 to 5.0 weight percent of the oil and the 2,5-di-mercapto-l,3,4-thiadiazole is present in an amount ranging from about 0.05 to 0.5 weight percent.
8. A lubricant as in claim 5 wherein the base oil is a paraffmic oil having from about 135 to 145 SUS/l00F viscosity.
9. A lubricant comprising:
a. a major amount of a base oil,
b. a minor amount of Bis (B-chlorophenethyl) disulfide,
I c. a minor amount of an alkyl derivative of 2,5-dimercapto-l ,3,4-thiadiazole and d. a minor amount of a mixture of alkylmaleic acid,
phenol and lauryl acid phosphate.
' 10. A lubricant comprising:
f. oil of citronella.