FR2842821A1 - Cutting oil formulation comprises one or more vegetable and/or synthetic oils and fatty acid esters, for use in machining operations such as turning, cutting and shaping - Google Patents

Abstract

A cutting oil comprises a vegetable or synthetic oil, or mixture of vegetable and/or synthetic oils, in which the oil or oil mixture contains one or more 20-24C fatty acids representing at least 30% of the total fatty acids present, and having ester bonds. An independent claim is also included for the use of the products.

Description

i The invention relates to a cutting oil based on vegetable oils,

  with a specific fatty acid profile.

  Cutting oils are lubricants used in metalworking. They make it possible, during stamping, turning, milling, cutting, polishing operations, to reduce friction between moving parts, to evacuate the heat produced in the work area and to eliminate the chips from parts work. Cutting oils therefore limit tool wear and lead to better finished parts, particularly in terms of surface quality and precision in

dimensions.

  In addition to these lubricating performances, the cutting oils must have other properties, in particular wetting properties with respect to the metal and the tool, anticorrosive properties with respect to the workpiece, anti-wear properties with respect to of the tool, and properties related to the structure of the fluid such as the mechanical stability of the emulsion or of the microemulsion, the thermal stability under the conditions of use, the

  bacterial stability due to the presence of water and organic matter.

  Being in contact with operators, cutting oils must still present very limited risks in terms of hygiene by being neither toxic,

  allergens or irritants for the respiratory tract and the skin.

  Cutting oils are usually made from oils

  mineral oil, to which various additives are added. These formulations have the disadvantage of being non-biodegradable and sometimes allergenic.

  There are also cutting oils formulated from oils

  plant. However, these oils have a fatty acid profile with medium and short chains, in any case less than 18 carbon atoms.

  In vegetable oils, the fatty acid profile is responsible for the technical and functional properties. The short-chain fatty acids 30 give the cutting oils good wettability, which makes it possible to increase the heat transfers and thus limit the wear of the tools. But these fatty acids with medium and short chains do not act on the power

lubricant as such.

  The applicant has therefore sought to formulate a cutting oil which exhibits excellent lubricating properties, while retaining the other properties desired in metalworking, in particular the

  wettability, anticorrosive power and biodegradability.

  It has therefore been found that it is possible to formulate a cutting oil exhibiting such properties using one or more vegetable and / or synthetic oils comprising one or more C20-C24 fatty acids, the said fatty acid (s) representing at least 30 %, preferably at least%, by weight of the total weight of the fatty acids present in the vegetable and / or synthetic oil (s), the said fatty acid (s) being used in

ester bonds.

  The invention therefore relates to a cutting oil comprising a vegetable or synthetic oil, or a mixture of vegetable and / or synthetic oils, the oil or mixture of vegetable and / or synthetic oils comprising one or more C20 fatty acids -C24, the said fatty acid (s) representing at least 30%, preferably at least 45%, by weight of the total weight of the fatty acids present in the oil or the mixture of vegetable oils

  and / or synthetic, the said fatty acid (s) being involved in ester bonds.

  By vegetable oil is meant any oil extracted from vegetable matter. By synthetic oil is meant an oil obtained by reaction of the fatty acid (s) with at least one alcohol, preferably a tri-alcohol,

preferably glycerol.

  By fatty acid is meant an aliphatic monocarboxylic acid having a chain of 4 to 40 carbon atoms, which can be saturated or

unsaturated.

  Among the C20-C24 fatty acid (s) used in the cutting oils according to the invention, there may be mentioned arachidonic, behenic acids,

  lignoceric, gadoleic, ketoleic, erucic and nervonic.

  Preferably, the C20-C24 fatty acid (s) are chosen from

C22 fatty acids.

  According to a first preferred embodiment, at least one fatty acid

in C22 is behenic acid.

  According to a second preferred embodiment, at least one fatty acid

in C22 is erucic acid.

  More preferably, the erucic acid represents at least 30%, better still at least 45%, by weight of the total weight of the fatty acids present in

  the oil or mixture of vegetable and / or synthetic oils.

  Among the vegetable oils comprising the erucic acid used according to the invention, there may be mentioned: - BRASSICA napus, the erucic fatty acid content of which is% by weight relative to the total weight of the fatty acids in the oil, - erucic colza, whose erucic fatty acid content is% by weight relative to the total weight of the fatty acids in the oil, - CRAMBE abyssinica, whose erucic fatty acid content is 59% by weight relative to total weight of the fatty acids in the oil, - CRAMBE Hispanica, whose erucic fatty acid content is 55% by weight relative to the total weight of the fatty acids in the oil,

  - SINAPIS alba, whose erucic fatty acid content is 54.5% by weight relative to the total weight of the fatty acids in the oil.

  Preferably, the oil or mixture of vegetable and / or synthetic oils constituting the cutting oil according to the invention further comprises one or more C10-C14 fatty acids, the said C10-C14 fatty acid (s) representing at least 5% by weight, preferably at least 10% by weight, of the total weight of the fatty acids present in the vegetable and / or synthetic oil (s), the said fatty acid (s) being involved in bonds

esters.

  The vegetable oil comprising at least one C10-C14 fatty acid may be any vegetable oil usually used for the formulation of oils

cutting.

  The C10-C14 fatty acid (s) used in cutting oils

  according to the invention are preferably chosen from C12 fatty acids.

  More preferably, at least one C12 fatty acid is lauric acid. Among the vegetable oils comprising lauric acid used according to the invention, mention may be made of LITSEA, CUPHEA calophylla,

  CINNAMOMUM iners, ACTINODAPHNE hookeri, COPHRA.

  The cutting oil according to the invention can be in the form

  of a whole oil, that is to say free of aqueous phase.

  The cutting oil can also be in the form of a solution, said solution being obtained by passing an oily phase s (comprising the vegetable and / or synthetic oil (s)) into an aqueous phase. The oily phase then preferably represents from 1 to 10% by

  weight of the total weight of the solution, better from 2 to 8% by weight.

  To facilitate dissolution, a cosolvent is advantageously used, for example propylene glycol ether, said cosolvent

  preferably representing from 10 to 50%, better still from 15 to 30% by weight of the total weight of the oily phase.

  The cutting oil can also be in the form of an emulsion or a microemulsion comprising at least one oily phase (comprising the vegetable and / or synthetic oil or oils) and at least one

aqueous phase.

  In this case, it is preferably an oil-in-water emulsion or microemulsion, the oily phase preferably representing

  from 1 to 10% by weight of the total weight of the emulsion, better from 2 to 8% by weight.

  The cutting oil then preferably comprises at least one emulsifier or a coemulsifier. This emulsifier or coemulsifier can be any type of emulsifier or coemulsifier conventionally used to formulate cutting oils. Mention may in particular be made of Skosan, sold by the company LUBRIZOL, Rewopal EO 60 sold

  by the company Goldsmidt, and their mixtures.

  The emulsifier or coemulsifier preferably represents from 10 to 50% by weight relative to the total weight of the oily phase, better still from 15

at 30% by weight.

  The cutting oil according to the invention can also comprise additives conventionally used in lubricants. Mention may in particular be made of anticorrosive agents, antimicrobial agents, sulfur and / or chlorinated lubrication additives, anti-foam agents, antioxidant agents and

their mixtures.

  The anticorrosive agents can be chosen from salts of fatty acids, alkanolamine, polycarboxylic acids, mono or diamines,

and their mixtures.

  Antimicrobial agents are particularly useful in cutting oils based on vegetable oils since microbial contamination is more marked there than in mineral oils. We can cite in particular the

  derivatives of triazine, morpholine, imidazole and mixtures thereof. However, the use of antimicrobial agents must be done without increasing the risk of toxicity, allergies and induced skin conditions.

  The sulfurized and / or chlorinated lubrication additives can be chosen from methyl esters of sulfurized vegetable oils, paraffins

chlorinated and their mixtures.

  The defoaming agents can be chosen from ethers of

polyoxyethylenated polysiloxanes.

  The antioxidant agents can be chosen from BHT and TBHQ. Preferably, all of the additives present in the cutting oil according to the invention represent at most 20% by weight of the total weight of the cutting oil. The cutting oil according to the invention is particularly suitable for

  be used during metal working operations.

  More particularly, it can be used during operations

  stamping, turning, milling, cutting, polishing, rolling, boring, sawing, stamping and peeling.

  The invention is illustrated by the following examples.

  The examples refer in particular to FIG. 1, which is a graph of the average diameter of the imprints left by three balls as a function of the load applied, in the "Extreme Pressure" test according to the CNOMO standard.

D-55 11 36.

  The technical tests have been set up and characterized according to the

  CNOMO standard - Standardization Committee for Tooling and Machine Tools.

  Three oils are the subject of these tests described in examples 1 to 5: an oil known as BIOCUTTOIL according to the invention - an oil based on vegetable oil from COLZA 00 - a mineral oil HCMineral BIOCUTTOIL oil comprises, by weight : - erucic rapeseed oil (comprising 45% by weight of erucic acid relative to the total weight of fatty acids in the oil):%, - cophra oil (comprising 50% by weight of lauric acid relative to the weight total fatty acids in the oil): 5% Rapeseed oil 00 is the New rapeseed oil (thus listed in the Codex alimentarus) in which the majority fatty acids are fatty acids with 18 carbon atoms, representing 60% by weight of the total weight of the fatty acids in the oil, the erucic fatty acid representing less than% by weight of the total weight of the fatty acids in the oil. Mineral oil is an oil based on 100 Neutral mineral oil whose composition, by weight, is as follows: - oil of petroleum origin type 100 Neutral: 75% - new rapeseed oil: 10% - sulfur olefin: 10% - calcium sulfonate: 5% In the examples which follow, these oils are found either in the form of whole oil (to form whole cutting oils), or are

  incorporated in aqueous phases to form cutting oils in the form of an emulsion or in the form of a solution.

  EXAMPLE 1 Test for Demonstrating the Lubricating Power of a Cutting Oil According to the Invention This test is carried out on whole cutting oils, that is to say made up of 100% oil and without additive, in order to observe the performances

actual cutting oils.

  The lubrication power of the oils is evaluated by means of an HFRR test (High Frequency Reciprocating Rig) on a

  "high frequency reciprocating bench", according to ISO 12156.

  The lubricating power of the cutting oil is determined by measuring the wear mark produced by the contact of an oscillating ball on a fixed plate immersed in the cutting oil and under closely controlled conditions. The weight of the ball is 200 g. It oscillates for 75 minutes at a frequency of 50 Hz. Two parameters serve as indicators: - the friction coefficient; the lower this parameter,

  the better the lubricating performance.

  - Scar X / Y which corresponds to the deformation diameter 10 of the ball; the higher this parameter, the greater the wear on the ball. Each test is carried out with a 300 ml sample of cutting oil.

  The results obtained are presented in Table 1.

TABLE 1

  Scar X / Y coefficient of friction (l m) Rapeseed 00 92.10-3 180

BIOCUTTOIL 88.10-3 134

  HCMinérale 87.10-3 250 The deformation diameter of the ball (SCAR X / Y) in the presence of BIOCUTTOIL cutting oil is less than that measured in the presence of rapeseed oil, and significantly less than that measured in presence of a mineral cutting oil. The wear of the ball is therefore limited in the presence of the BIOCUTTOIL cutting oil, which shows the superior lubricating power of the cutting oils according to the invention, in particular compared to a conventional vegetable cutting oil such as '' an oil based

rapeseed.

  EXAMPLE 2 Demonstration of the lubricating power of a cutting oil according to the invention by the "Extreme Pressure" test (4 ball test) according to standard CNOMO D-551136 The three cutting oils tested are each in the form of 'a

  5% oil in 95% water emulsion.

  The emulsion is made self-emulsifiable using a mixture of

  two emulsifiers, present at 20% by weight for 80% oil.

  The mixture of the two emulsifiers consists of 75% by weight (relative to the weight of the mixture) of Skosan marketed by the company

  LUBRIZOL and 25% by weight of ethoxylated castor oil.

  The extreme pressure test assesses the properties of

  lubrication of cutting oils under extreme conditions.

  The device consists of a steel ball, rotating on 3 balls held stationary in a support. The rotation speed of the ball

higher is 1450 rpm.

  A series of 4-ball tests lasting one minute are carried out under increasing loads. For each load, an average diameter of the imprints left on the 3 lower balls is evaluated. A curve 20 retracing the evolution of this diameter as a function of the applied load

  characterizes the extreme pressure properties of the lubricant (Figure 1).

  To understand these results, we must first determine the different working areas of the tool (represented by the 4 balls) with the 3 oils and thus define the particular properties of each fluid.

  The 4 ball test allows, in the most general case, to define 4 zones or areas of work according to the applied load (cf. figure 1): - Hydrodynamic lubrication area, which is the "ideal" area of work for the machine. This zone generates only limited and superficial wear thereof. In this case, small variations in the wear diameter of the ball are observed compared to an increase.

regular charge.

  - Limiting friction area, which marks a first setback.

  There is a sharp increase in the wear diameter of the ball for

  a slight increase in the load before seizing.

  - Grab area. The fluid no longer does its job of protection.

  There is a significant degradation (large diameter of wear of the ball)

  but stable for increasing pressure loads.

  - Welding of the balls: total immobility of the machine.

  In Figure 1, index 1 relates to mineral cutting oil, index 2 to rapeseed cutting oil and index 3 to cutting oil

BIOCUTTOIL according to the invention.

  The results for the three cutting oils tested are presented

in table 2.

TABLE 2

  Field of Field of Field of Welding lubrication friction hydrodynamic binding limit e HCMineral 600 to 700 N 700 to 800 N 900 N Rapeseed oil 600 to 800 N 800 to 900 N 1000 N

00..

  Biocuttoil 600 to 900 N 900 to 1000 N The BIOCUTTOIL cutting oil according to the invention compared to the mineral cutting oil is clearly more efficient. The range of hydrodynamic lubrication is wider for BIOCUTTOIL and the welding load

  intervenes faster for mineral cutting oil.

  The behavior of the BIOCUTTOIL cutting oil is also significantly better than the cutting fluid formulated with rapeseed 00. These 20 results show a longer lubrication range in optimal condition

  (significant difference of 100 N) in the case of BIOCUTTOIL which gives it more interesting lubrication properties under extreme loads.

  In addition, with BIOCUTTOIL we do not observe seizure on

high pressures.

  We should therefore observe a good maintenance of the production tool

  state for significant pressures. It is also a safety margin for fluid users when pressure peaks appear on tools during production.

  EXAMPLE 3 Test "anticorrosive" in contact with non-ferrous metals according to standard CNOMO D 63 5223 The purpose of this test is to evaluate the anticorrosive properties of a

  cutting oil in contact with non-ferrous metals.

  The three cutting oils tested are each in the form of a

5% oil in 95% water solution.

PRINCIPLE

  A metal test piece is partially submerged during a

  time determined in the cutting oil under test.

  The aggressiveness of the cutting oil on the metal is appreciated by

  variations in the appearance of the cutting oil and the metallic test piece (corrosion). A score, according to the standardized rating provided by CNOMO D 63 5223, is then given to the 2 criteria. This rating is higher the higher the corrosion.

MATERIALS

  Copper test piece: NF - A - 51 - 050 Bronze test piece: NF - A - 51 108 25. Aluminum test piece: NF - A - 50 - 411

RESULTS

  The results are presented in Table 3.

he

TABLE 3

  Copper Bronze Aluminum Sample Liquid Test Tube Liquid Test Liquid test te te te HCMineral 0 0 2 2 2 1 Cutting oil 0 0 1 1 0 0 rapeseed 01 Biocuttoil OOII O- O The aggressiveness of the cutting oil according to the invention is comparable to that of rapeseed oil 00. On the other hand, it is weaker on bronze than the aggressiveness of mineral oil, and much weaker on aluminum. The BIOCUTTOIL cutting oil according to the invention therefore retains the

  anticorrosive power in addition to its lubricating power.

  EXAMPLE 4 Test of the wetting power of a cutting oil according to the invention according to standard CNOMO D 65-1662 The purpose of this test is to evaluate the wetting power of

  cutting (contact power between the oil and the materials to be worked).

  The three cutting oils tested are each in the form of a

5% oil in 95% water solution.

PRINCIPLE

  On a suitable device, a disc of unbleached cotton cloth is

  kept immersed in the cutting oil to be tested.

  The wetting power is determined by measuring the time after which the disc begins to sink into the liquid. This power will

  therefore given by the value of time expressed in seconds.

EQUIPMENT

ASPA cotton, diameter 3 cm

RESULTS

  The results are presented in Table 4.

TABLE 4

  Samples Time in seconds HCMineral 282 Rapeseed cutting oil 00 14

BIOCUTTOIL 74

  Reference 55 (standard: 50 - / + 10) The wettability behavior observed in these tests shows a very significant superiority of vegetable cutting oils, and in particular 10 of cutting oil according to the invention compared to mineral cut. EXAMPLE 5 Exfoliation tendency test according to CNOMO D 651663 The three oils tested are in the form of whole oil (as in

Example 1).

  This test makes it possible to assess the tendency for gumming of aqueous machining liquids and therefore their clogging effects on production tools. In fact, the oils, despite the refining, in the long run deposit rubber films on the metal or come to stick metal shavings. On the other hand, these phenomena make the control windows of the windows opaque.

  machines and interfere with quality control.

  A volume of liquid to be examined at working concentration in which a platinum ring is immersed is subjected to evaporation. The tendency to

  gumming of the cutting oil is evaluated by measuring the force necessary to tear off the platinum ring in the absence of water and in the presence of water.

  This measurement will therefore be expressed by the force per unit of length

necessary to tear off the ring.

TEST CONDITIONS

  - volume: 1 mI - duration: 72 hours - temperature: oven at 85 0C +/- 10C

RESULTS

  The results are presented in Table 5.

TABLE 5

  Results (mN / m) Rapeseed cutting oil 00 36

BIOCUTTOIL 34

  HCMineral 22 Reference value (mineral base) 30

CONCLUSION

  As shown in the table above, the observed scrub values are of the same order of magnitude, the reference for this type of

test revolving around 30 mN / m.

  We can conclude that these 3 fluids do not clog and do not represent a constraint for industrial use. Thus, the BIOCUTTOIL cutting oil 20 according to the invention, in addition to its lubricating performance, does not exhibit any significant difference in behavior at

  scrub compared to vegetable oils.

Claims (23)

  1. Cutting oil comprising a vegetable or synthetic oil, or a mixture of vegetable and / or synthetic oils, characterized in that the oil or mixture of vegetable and / or synthetic oils comprises one or more C20 fatty acids -C24, the said fatty acid (s) representing at least 30% by weight of the total weight of the fatty acids present in the oil or the mixture of vegetable and / or synthetic oils, the said fatty acid (s)   being engaged in ester bonds.   2. Cutting oil according to claim 1 characterized in that the synthetic oil or oils are obtained by reaction of the said fatty acid (s) with at least one alcohol, preferably a tri-alcohol, more preferably glycerol.   3. Cutting oil according to claim 1 or 2 characterized in that   the C20-C24 fatty acid (s) represent at least 45% by weight of the total weight of the fatty acids present in the vegetable and / or synthetic oil (s).   4. Cutting oil according to any one of the preceding claims, characterized in that the C20-C24 fatty acid (s) are   chosen from arachidonic, behenic, lignoceric, gadoleic acids,   ketoleic, erucic and nervonic.   5. Cutting oil according to any one of the preceding claims, characterized in that the C20-C24 fatty acid (s) are   chosen from C22 fatty acids.   6. Cutting oil according to claim 5 characterized in that at   minus one C22 fatty acid is behenic acid.   7. Cutting oil according to claim 5 characterized in that at   minus one C22 fatty acid is erucic acid.   8. Cutting oil according to claim 7 characterized in that the erucic acid represents at least 30%, preferably at least 45%, by weight of the total weight of the fatty acids present in the vegetable oil or oils and / or synthetic.   9. Cutting oil according to claim 7 or 8 characterized in that the vegetable oil or oils comprising erucic acid are chosen from   BRASSICA napus, COLZA erucique, CRAMBE abycissinica, CRAMBE Hispanica and SINAPIS alba.   10. Cutting oil according to any one of the preceding claims, characterized in that the oil or the mixture of vegetable oils   and / or synthetic comprises one or more C10-C14 fatty acids, the said C10-C14 fatty acid (s) representing at least 5% by weight, preferably at least 10% by weight of the total weight of fatty acids present in the oil or the mixture of vegetable and / or synthetic oils, the said fatty acid (s) being involved in ester bonds. 11. Cutting oil according to claim 10 characterized in that the   or the C10-C14 fatty acids are chosen from C12 fatty acids.   12. Cutting oil according to claim 11 characterized in that   at least one C12 fatty acid is lauric acid.   13. Cutting oil according to claim 12 characterized in that the vegetable oils comprising lauric acid are chosen from   LITSEA, CUPHEA calophylla, CINNAMOMUM iners, ACTINODAPHNE hookeri and COPHRA.   14. Cutting oil according to any one of the preceding claims, characterized in that it is in the form of an oil whole.   15. Cutting oil according to any one of claims 1 to 13 characterized in that it is in the form of a solution, said   solution being obtained by passing an oily phase into an aqueous phase, the oily phase preferably representing from 1% to 10% in   weight of the total weight of the solution, better from 2% to 8% by weight.   16. Cutting oil according to claim 15 characterized in that the solution comprises at least one cosolvent, preferably propylene glycol ether, preferably representing from 10 to 50%, better still from 15 to 30%, in   weight of the total weight of the oily phase.   17. Cutting oil according to any one of claims 1 to 13   characterized in that it is in the form of an emulsion or a microemulsion comprising at least one oily phase and at least one aqueous phase.   18. Cutting oil according to claim 17 characterized in that it is in the form of an emulsion or a   oil-in-water microemulsion, the oily phase representing from 1% to 10% by weight of the total weight of the emulsion, preferably from 2% to 8% by weight.   19. Cutting oil according to claim 17 or 18 characterized in that it comprises at least one emulsifier or co-emulsifier, preferably representing from 10 to 50%, better still from 15 to 30%, by weight of the total weight of the oily phase.   20. Cutting oil according to any one of the preceding claims, characterized in that it comprises at least one selected additive   among anticorrosive agents, antimicrobial agents, blown and / or chlorinated lubrication additives, anti-foaming agents, agents antioxidants and their mixtures.   21. Cutting oil according to claim 20, characterized in that the additive (s) represent at most 20% by weight of the total weight of the oil cutting.   22. Use of cutting oil as defined in one   any of claims 1 to 21 for the work operations of   metals. 23. Use according to claim 22 characterized in that the metal working operations are stamping, turning, milling, cutting, polishing, rolling, boring operations,   sawing, stamping or peeling.