WO2013147136A1

WO2013147136A1 - Lubricating oil composition for metalworking

Info

Publication number: WO2013147136A1
Application number: PCT/JP2013/059488
Authority: WO
Inventors: 順英谷野; 真由長谷川
Original assignee: 出光興産株式会社
Priority date: 2012-03-30
Filing date: 2013-03-29
Publication date: 2013-10-03
Also published as: JP2013213115A; JP5898554B2

Abstract

Provided is a lubricating oil composition for metalworking that can simultaneously offer high load resistance performance and exceptional cleaning properties without requiring a chlorine-based oil to be used, and can be used under severe lubricating conditions such as steel pipe expansion processing by using a lubricating oil composition containing (a) a base oil, (b) a metal sulfonate, (c) an active polysulfide, (d) a fatty acid partial ester of a polyhydric alcohol, and (e) a non-ionic surfactant; and having a kinematic viscosity at 40°C of 50 to 1000 mm²/s.

Description

Lubricating oil composition for metal working

The present invention relates to a lubricating oil composition for metal working, and more particularly to a lubricating oil composition for metal working used under severe lubricating conditions such as steel pipe expansion.

Lubricating oils used for metal processing are usually required to have excellent load bearing performance because they are used under severe lubricating conditions. Moreover, since the lubricating oil used for metal processing needs to be removed by washing the lubricating oil adhering to the workpiece after metal processing, it is also required to have excellent cleaning properties.
Among metal processing, for example, in steel pipe expansion processing such as mechanical steel pipe expansion (mechanical expander), a steel pipe having a diameter of 30 inches or more, a thickness of 6 to 25 mm, and a length of 10 m or more is usually used as a workpiece. Thus, the pipe is formed and the steel pipe having tough strength is expanded by the expander. In this expansion process, a very large surface pressure is applied to the sliding portion formed by the inner surface of the tube and the expansion member of the expander. Therefore, the lubricating oil used for steel pipe expansion processing is required to have extremely high load bearing performance.
Moreover, in the steel pipe expansion process, after processing, the oil adhering to the steel pipe is washed with warm water also serving as a water pressure inspection. Therefore, the lubricating oil used for steel pipe expansion processing is required to have excellent cleaning properties.

Conventionally, chlorinated oil has been used as a lubricating oil for steel pipe expansion processing. Chlorine-based oils have high polarity due to the use of chlorine, have excellent load bearing performance, and also have excellent detergency that can be washed away with water in steel pipe expansion processing.
However, the movement to abolish chlorinated oils is spreading from the viewpoint of reducing environmental impact, and the development of non-chlorinated lubricants that realize this is being promoted worldwide.

For example, Patent Document 1 proposes to use water-soluble polyethylene glycol as a lubricant for steel pipe expansion processing.
However, although water-soluble polyethylene glycol has detergency, load-bearing performance is reduced. Therefore, in order to improve lubricity, an excessively high viscosity oil agent must be used, which is inferior in handling. Further, the high-pressure viscosity of the water-soluble substrate is very low, and the sliding portion having a high surface pressure cannot be lubricated, and seizure occurs.
Thus, it turns out that the method of using water-soluble polyethylene glycol has room for improvement in terms of load bearing performance and handling.
In addition, the sulfur-based oil agent that is most often used as an alternative to the chlorine-based oil agent cannot achieve its purpose because it cannot provide cleaning properties even if it can provide load bearing performance.
Under such circumstances, development of a metal processing lubricant, particularly a steel pipe expansion lubricant, having high load-bearing performance and excellent cleanability without using a chlorinated oil is desired.

JP 58-21490 A

The present invention is a metalworking lubrication that has high load-bearing performance and excellent cleaning properties without using a chlorinated oil, and can be used under severe lubrication conditions such as steel pipe expansion. The object is to provide an oil composition.

The present inventors have found that a composition obtained by combining specific additives can achieve its purpose. The present invention has been completed based on such findings. That is, the present invention

1. (A) a base oil, (b) a metal sulfonate, (c) an active polysulfide, (d) a fatty acid partial ester of a polyhydric alcohol, and (e) a nonionic surfactant. A lubricating oil composition for metal working, wherein the viscosity is 50 mm ² / s or more and 1000 mm ² / s or less,
2. (C ′) the lubricating oil composition for metalworking according to 1 above, further comprising powdered sulfur,
3. The lubricating oil composition for metalworking according to 1 or 2 above, wherein the base oil as component (a) comprises mineral oil or one or more selected from mineral oil and ester synthetic oil and polymethacrylate,
4). 4. The lubricating oil composition for metal processing according to 3 above, wherein the ester-based synthetic oil is an ester of a polyhydric alcohol having 2 to 6 carbon atoms and an aliphatic acid having 2 to 24 carbon atoms,
5. The lubricating oil composition for metal working according to any one of 1 to 4 above, wherein the metal sulfonate as component (b) is an overbased alkaline earth metal sulfonate,
6). The lubricating oil composition for metal working according to any one of 1 to 5 above, wherein the sulfur content of the active polysulfide as the component (c) is 20% by mass or more,
7). 7. The metal processing according to any one of 1 to 6 above, wherein the fatty acid partial ester of the polyhydric alcohol as component (d) is a partial ester of a polyhydric alcohol having 2 to 6 carbon atoms and a fatty acid having 6 to 24 carbon atoms. Lubricating oil composition,
8). The lubricating oil composition for metal processing according to any one of 1 to 7 above, wherein the nonionic surfactant as the component (e) is a polyoxyalkylene type nonionic surfactant,
9. 9. The lubricating oil composition for metal working according to 8 above, wherein the polyoxyalkylene type nonionic surfactant has a polyoxyethylene group and a polyoxypropylene group,
10. (B) 1% by mass or more and 20% by mass or less of metal sulfonate, (c) 2% by mass or more and 25% by mass or less of active polysulfide, (c ′) 3% by mass or less of powder sulfur, 10. The metal processing according to any one of 1 to 9 above, comprising 1% by mass to 20% by mass of a fatty acid partial ester of a polyhydric alcohol, and (e) 2% by mass to 25% by mass of a nonionic surfactant. Lubricating oil composition,
11. The lubricating oil composition for metal working according to any one of 1 to 10 above, which is used for steel pipe expansion processing,
Is to provide.

According to the present invention, even without using a chlorine-based oil agent, it has a high load-bearing performance and at the same time has excellent cleaning properties, and can be used under severe lubrication conditions such as steel pipe expansion processing. A lubricating oil composition can be provided.

The lubricating oil composition for metal processing of the present invention comprises (a) a base oil, (b) a metal sulfonate, (c) an active polysulfide, (d) a fatty acid partial ester of a polyhydric alcohol, and (e) a nonionic interface. It contains an active agent, and the kinematic viscosity at 40 ° C. of the composition is from 50 mm ² / s to 1000 mm ² / s.

[(A) Base oil]
The base oil used as the component (a) in the present invention is not particularly limited, and can be appropriately selected from known mineral base oils and synthetic base oils that have been used conventionally.
Here, as the mineral oil base oil, for example, a distillate obtained by atmospheric distillation of paraffinic crude oil, intermediate (base) crude oil, or naphthenic crude oil, or vacuum distillation of residual oil of atmospheric distillation. Or refined oils obtained by refining them according to conventional methods (for example, solvent refined oil, hydrorefined oil, hydrocracked oil, dewaxed oil, clay-treated oil, mineral oil-based wax, Fischer-Tropsch process, etc. And the like (base oil produced by isomerizing a gas-liquid liquid).
On the other hand, examples of synthetic oils include poly-α-olefins, which are α-olefin oligomers having 8 to 14 carbon atoms, ester-based synthetic oils such as polybutene and polyol esters, aromatic hydrocarbons such as alkylbenzene, and polymethacrylates. Mention may be made of molecular compounds.
In the present invention, as the base oil, one kind of the above mineral oil may be used, or two or more kinds may be used in combination. Moreover, the said synthetic oil may be used 1 type and may be used in combination of 2 or more type. Further, one or more mineral oils and one or more synthetic oils may be used in combination.

The base oil in the present invention preferably has a kinematic viscosity at 40 ° C. of 50 mm ² / s to 1000 mm ² / s, and more preferably 100 mm ² / s to 800 mm ² / s.
If the base oil has a kinematic viscosity at 40 ° C. of less than 50 mm ² / s, the oil film under high surface pressure may break, and the performance as a lubricating oil may be insufficient. On the other hand, if it exceeds 1000 mm ² / s, it may be difficult to handle with a normal pump, and there may be a residual after washing with warm water.

In the present invention, a base oil containing a mineral oil (mineral oil base oil) is preferable as the base oil. For example, a mineral oil (mineral oil only), or one or more selected from mineral oil, an ester synthetic oil, and polymethacrylate is used. The inclusion is more preferable. Mineral oil includes a mixture of two or more mineral oils.
By using a base oil containing a mineral oil, it is possible to enhance the detergency and to keep the dissolution stability (mixing stability) of the composition good.
Moreover, load-bearing performance can be further improved by mix | blending 1 or more types chosen from ester synthetic oil and polymethacrylate with the mineral oil.

The blending ratio of mineral oil to one or more selected from ester synthetic oil and polymethacrylate in the case of mixing and using ester synthetic oil or polymethacrylate in mineral oil is not particularly limited, but usually [mineral oil]: The mass ratio of [one or more selected from ester-based synthetic oils and polymethacrylates] is preferably in the range of 70:30 to 40:60. When the blending ratio of both is within the above range, a composition satisfying the dissolution stability of the composition at the same time as the washing performance and load bearing performance can be obtained.

The mineral oil used in the present invention may be any of paraffinic mineral oil, intermediate (base) mineral oil, or naphthenic mineral oil as described above, but naphthenic mineral oil has better detergency and dissolution stability of the oil agent. It is preferable at the point which can be maintained.
The kinematic viscosity at 40 ° C. of the mineral oil, 20 mm ² / s or more 1000 mm ² / s can be used following ones, the following are more preferable 30 mm ² / s or more ^{^{800mm 2 / s, 80mm 2 /}} s or more 500 mm ² Particularly preferred is / s or less. Specific examples of preferred mineral oils include, for example, bright stock oil (BS) and 500 neutral oil (500 N), and particularly preferred is bright stock oil or a mixture of bright stock oil and 500 neutral oil.

As the ester synthetic oil used in the present invention, an ester compound having two or more ester bonds in the molecule can be used.
Examples of such ester compounds include polyol esters formed from polyhydric alcohols and fatty acids.
As the polyhydric alcohol that forms the polyol ester, dihydric to hexahydric ones are usually used. Preferred polyhydric alcohols include, for example, ethylene glycol, propylene glycol, neopentyl glycol, glycerin, trimethylol ethane, trimethylol propane, pentaerythritol, sorbitan and the like. Of these, trimethylolpropane and pentaerythritol are more preferable.
On the other hand, the fatty acid forming the polyol ester is preferably a monobasic acid, and usually a fatty acid having 2 to 24 carbon atoms is used. The fatty acid may be linear or branched, and may be saturated or unsaturated. Among these, a saturated fatty acid having 8 to 22 carbon atoms or an unsaturated fatty acid is preferable, and a saturated fatty acid having 12 to 18 carbon atoms or an unsaturated fatty acid is more preferable.
Typical examples of the ester synthetic oil formed from the polyhydric alcohol and the fatty acid include trimethylolpropane or pentaerythritol having 8 to 22 carbon atoms, more preferably 12 to 18 carbon atoms, and particularly preferably 16 to 18 carbon atoms. The fatty acid esters are preferred.

As the polymethacrylate in the present invention, those conventionally known as viscosity index improvers can be used. Therefore, the polymethacrylate used in the present invention may be either a dispersion type or a non-dispersion type. The mass average molecular weight is preferably 10,000 or more and 1,000,000 or less, more preferably 50,000 or more and 800,000 or less, and still more preferably 100,000 or more and 700,000 or less. When the mass average molecular weight is 10,000 or more and 1,000,000 or less, a thickening effect can be imparted and load bearing performance can be enhanced.

[(B) Metal sulfonate]
In the present invention, various metal salts can be used as the metal sulfonate used as the component (b). Among these, alkaline earth metal sulfonates such as Ca, Mg, and Ba are preferable from the viewpoint of enhancing the load bearing performance. Of these, Ca sulfonate and Mg sulfonate are more preferable, and Ca sulfonate is particularly preferable.
Further, the metal sulfonate may be neutral, basic, or overbased, but it is an overbased Ca sulfonate, specifically, a base number by the perchloric acid method is 150 mgKOH / g or more. A Ca sulfonate of 500 mgKOH / g or less is preferable, and a Ca sulfonate of 250 mgKOH / g or more and 500 mgKOH / g or less is particularly preferable.
In the present invention, the content of the metal sulfonate as the component (b) is preferably 1% by mass or more and 20% by mass or less, more preferably 3% by mass or more and 15% by mass or less based on the total amount of the composition. If the content of the metal sulfonate is 1% by mass or more, the effect of improving the load bearing performance is exhibited, and if it is 20% by mass or less, the dissolution stability can be kept good.

[(C) active polysulfide, etc.]
In the present invention, active polysulfide is used as the component (c). As the active polysulfide, for example, dihydrocarbyl polysulfide represented by the following general formula (1) is preferably used.
R ¹ -S _x -R ² (1)
In the above formula, each of the hydrocarbyl groups R ¹ and R ² independently represents an alkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkylaryl group, or an arylalkyl group, It may be the same or different. x represents an integer of 2 to 10.
The hydrocarbyl group of R ¹ and R ² is more preferably an alkyl group having 6 to 18 carbon atoms. As the alkyl group, a linear or branched, saturated or unsaturated alkyl group is used. it can.
As representative examples of active polysulfide, any of linear or branched dihexyl polysulfide, dioctyl polysulfide, dinonyl polysulfide, didecyl polysulfide, didodecyl polysulfide, diundecyl polysulfide, ditetradecyl polysulfide, dihexadecyl polysulfide, Examples thereof include polysulfide having a branched alkyl group having 6 to 15 carbon atoms derived from dioctadecyl polysulfide, propylene or isobutylene. Among these, dialkyl polysulfides having an alkyl group having 8 to 16 carbon atoms are preferable.
The sulfur content of the active polysulfide is preferably 20% by mass or more and particularly preferably 30% by mass or more in order to improve load bearing performance.
The content of the active polysulfide as the component (c) in the present invention is preferably 2% by mass or more and 25% by mass or less, more preferably 5% by mass or more and 20% by mass or less based on the total amount of the composition. If the content of the active polysulfide is 2% by mass or more, the load bearing performance is satisfactorily exhibited, and if it is 25% by mass or less, corrosion does not become a problem.

In the present invention, powdered sulfur can be included as the component (c ′) together with the active polysulfide. This can further enhance the load bearing performance.
When blending this powder sulfur, the blending amount is not particularly limited, but is preferably 0.05% by mass or more and 3% by mass or less, more preferably 0.1% by mass or more and 1% by mass or less based on the total amount of the composition. Preferably, 0.2 mass% or more and 0.7 mass% or less are more preferable, and 0.3 mass% or more and 0.5 mass% or less are especially preferable. If the content of powdered sulfur is 0.05% by mass or more, the effect of further enhancing the load bearing performance of the composition of the present invention is exhibited. Moreover, if content of powder sulfur is 3 mass% or less, there is no possibility that powder sulfur will precipitate.

[(D) Polyhydric alcohol fatty acid partial ester]
In the present invention, a fatty acid partial ester of a polyhydric alcohol is used as the component (d).
As the polyhydric alcohol, those having 2 to 6 valences are usually used. Specific examples thereof include ethylene glycol, propylene glycol, neopentyl glycol, glycerin, trimethylol ethane, trimethylol propane, pentaerythritol, sorbitan and the like. Among these, glycerin and sorbitan are preferable, and glycerin is particularly preferable.
As the fatty acid that forms the fatty acid partial ester, a fatty acid having 6 to 24 carbon atoms is usually used. The fatty acid may be linear or branched, and may be saturated or unsaturated. Among these, fatty acid having 12 to 22 carbon atoms is preferable, saturated or unsaturated fatty acid having 16 to 18 carbon atoms is more preferable, and oleic acid is particularly preferable from the viewpoint of effects and availability.
When the polyhydric alcohol is glycerin, the fatty acid partial ester as the component (d) includes glycerin monoester (monoglyceride) and glycerin diester (diglyceride). In the present invention, glycerin monoester (monoglyceride) is more preferable.
In this invention, it is preferable to mix | blend the said (d) component in the range of 1 mass% or more and 20 mass% or less based on the composition whole quantity, and it is more preferable to mix | blend in the range of 2 mass% or more and 15 mass% or less. preferable. When the content of the component (d) is in the above range, the load bearing performance is improved and the dissolution stability of the composition is not impaired.

[(E) Nonionic surfactant]
The nonionic surfactant used as the component (e) in the present invention may be any type such as a polyhydric alcohol type nonionic surfactant and a polyoxyalkylene type nonionic surfactant.
In the present invention, the nonionic surfactant is blended mainly for imparting detergency to the lubricating oil composition. Therefore, it is preferable to easily adjust HLB (hydrophilic lipophilic balance), and polyoxyalkylene nonionic surfactants that can easily be obtained from various HLBs are particularly preferably used.
As such a nonionic surfactant, polyoxyethylene alkyl ether (however, the alkyl group constituting the alkyl ether preferably has 6 to 18 carbon atoms), polyoxyethylene polyoxypropylene alkyl ether ( However, polyoxyethylene polyoxypropylene may be random copolymerization or block copolymerization, and the alkyl group constituting the alkyl ether preferably has 6 to 18 carbon atoms).
Such nonionic surfactants may be used alone or in combination of two or more.
In this invention, it is preferable to mix | blend the said (e) component in the range of 2 mass% or more and 25 mass% or less based on the composition whole quantity, and 3 mass% or more and 20 mass% or less are more preferable. (E) If content of a component is 2 mass% or more, detergency will improve and if it is 25 mass% or less, the mixing stability of an oil agent will not deteriorate.

[Other additives]
The present invention comprises the components (a) to (e) or (a) to (e) and (c ′) described above, but further impairs the object of the present invention as desired. For example, various additives such as an antioxidant, a rust inhibitor, a corrosion inhibitor, and an antifoaming agent can be blended within the range.
Examples of the antioxidant include phenolic antioxidants such as 2,6-di-tert-butyl-4-methylphenol and 4,4′-methylenebis (2,6-di-tert-butylphenol), phenyl Examples thereof include amine-based antioxidants such as -α-naphthylamine and 4,4'-dioctyldiphenylamine.
Examples of the rust inhibitor and corrosion inhibitor include fatty acid, alkenyl succinic acid half ester, fatty acid soap, alkyl sulfonate, fatty acid amine, paraffin oxide, alkyl polyoxyethylene ether, and the like.
Examples of the antifoaming agent include dimethylpolysiloxane and polyacrylate.
These additives can be used individually by 1 type or in mixture of 2 or more types. Moreover, the compounding quantity of these additives is normally mix | blended at 0.0001 mass% or more and 3 mass% or less on the basis of the composition whole quantity, respectively.

[Lubricating oil composition for metal working]
The lubricating oil composition for metal working of the present invention has a kinematic viscosity at 40 ° C. of 50 mm ² / s to 1000 mm ² / s, preferably 100 mm ² / s to 500 mm ² / s, more preferably 110 mm ² / s. s to 300 mm ² / s.
If the kinematic viscosity at 40 ° C. of the composition is 50 mm ² / s or more, the oil film is prevented from being broken under high surface pressure and the performance as a lubricating oil is exhibited. If the composition is 1000 mm ² / s or less, the viscosity is It is not too high to be handled with a pump, and no residual material is generated when washing with hot water.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
In addition, the property and performance of the metalworking oil composition obtained in each example were determined according to the following method.
(1) Kinematic viscosity According to JIS K2283, the kinematic viscosity at 40 ° C was measured.
(2) Base number It measured based on the perchloric acid of JISK2501.
(3) Sulfur content Measured according to JIS K2541.

(4) Draw bead test (test method)
Using a draw bead test device with a structure that pulls out the workpiece and measures its pulling load while holding the plate-like workpiece between two beads (punch) from both sides, a drawing experiment was conducted under the following conditions. .
(I) Work material: material S45C, shape 4.5 mm (thickness) × 15 mm × 300 mm, hardness HV275
(Ii) Punch: Material Cemented carbide, shape 0.5R
(Iii) Presser load: 400 kgf (surface pressure: 3000 MPa)
(Iv) Drawing speed: 5 mm / min.
(V) Lubricant application method: Brush application (evaluation method)
(I) Pull-out load The pull-out load when 60 mm was pulled was measured. It shows that a low pull-out load is good.
(Ii) Surface damage The surface of the workpiece when it was pulled out by 60 mm was observed, and the presence and extent of damage due to seizure or galling was measured visually. The damage area was evaluated as the degree of damage based on the following evaluation criteria.
(Evaluation criteria)
None: No damage on both sides Fine: Scratches less than 10% of surface area on one side Small: Scratches of 10% to 30% of surface area on one side Medium: Scratches of 30% or less of surface area on both sides Large: Surface area on both sides There are more than 30% of scratches

(5) Detergency test (test method)
An SPCC plate (60 mm × 80 mm × 0.7 mm (thickness)) was dipped in the oil, and then suspended for 30 minutes to drain the oil. Subsequently, it was washed with a warm water (40 ° C.) shower with a water pressure of 40 kgf / cm ² for 40 seconds and further immersed in running water. Thereafter, the wetted area was visually measured and evaluated according to the following criteria.
(Evaluation criteria)
A: The wetted area exceeds 70% B: The wetted area exceeds 40% and is 70% or less C: The wetted area is 40% or less

<Examples 1 to 8 and Comparative Examples 1 to 5>
Using the base oils and additives shown in Tables 1 and 2 and mixing at the ratios shown in Tables 1 and 2, metalworking fluids were prepared, and their properties and performance were determined. The results are shown in Tables 1 and 2.

[Supplement under Rule 26 15.04.2013]

[Supplement under Rule 26 15.04.2013]

[note]
1) Naphthenic bright stock (40 ° C. kinematic viscosity: 433.8 mm ² / s, sulfur content: 0.04 mass%)
2) Naphthenic 500 neutral (40 ° C. kinematic viscosity: 104.7 mm ² / s, sulfur content: 0.04 mass%)
3) Paraffin-type bright stock (40 ° C. kinematic viscosity: 435.1 mm ² / s, sulfur content: 0.02% by mass)
4) Paraffin-based 500 neutral (40 ° C. kinematic viscosity: 90.48 mm ² / s, sulfur content 0.01 mass%)
5) Ester-based synthetic oil (pentaerythritol tetraoleate, 40 ° C. kinematic viscosity: 4.71 mm ² / s)
6) Polymethacrylate (non-dispersed, mass-average molecular weight (Mw): 550,000, diluted to 150 neutral mineral oil at a concentration of 35% by mass)
7) Metal sulfonate (calcium sulfonate, Ca content: 12.5% by mass, sulfur content: 2.4% by mass, base number (perchloric acid method): 320 mgKOH / g)
8) Active polysulfide (dilauryl polysulfide represented by the following chemical formula (2), sulfur content: 32% by mass)
C ₁₂ H ₂₅ -S ₅ -C ₁₂ H ₂₅ (2)
9) Phosphorus extreme pressure agent (Dioleyl hydrogen phosphite)
10) Powdered sulfur (Sulfur content: 99.8% by mass or more)
11) Partial ester of polyhydric alcohol (oleic acid monoglyceride)
12) Nonionic surfactant-1 (polyoxyethylene polyoxypropylene alkyl ether (block type, the alkyl group has 10 to 13 carbon atoms), HLB: 12.7)
13) Nonionic surfactant-2 (polyoxyethylene oleyl ether, HLB: 8.8)

From Tables 1 and 2, it can be seen that the compositions of Examples 1 to 8 of the present invention have a drawing load in a draw bead test of 260 kgf or less, almost no surface damage, and good cleanability.
On the other hand, Comparative Example 1 which does not contain the component (b) has a high pulling load (288 kgf) and a large surface damage.
Moreover, the comparative example 2 which does not contain (c) component (active polysulfide) has a high extraction load (330 kgf), and its surface damage is also large. Moreover, the comparative example 3 which mix | blended the phosphorus extreme pressure agent with the comparative example 2 which does not contain (c) component (active polysulfide) has shown that neither a drawing load nor surface damage fully recovers.
Furthermore, the comparative example 4 which does not contain the component (d) has a high pulling load (270 kgf), and the surface damage is also poor. Moreover, the comparative example 5 which does not contain (e) component is inferior in washability.

According to the lubricating oil composition for metal working of the present invention, even without using a chlorinated oil, it has a high load-bearing performance and at the same time has an excellent cleaning property, and is subjected to severe lubrication conditions such as steel pipe expansion processing. A metalworking lubricating oil composition that can be used below can be provided. Therefore, it can be effectively used as a high-performance lubricating oil composition for metal working that has solved environmental problems.

Claims

(A) a base oil, (b) a metal sulfonate, (c) an active polysulfide, (d) a fatty acid partial ester of a polyhydric alcohol, and (e) a nonionic surfactant. A lubricating oil composition for metal working, wherein the viscosity is 50 mm 2 / s or more and 1000 mm 2 / s or less.
The metal working lubricating oil composition according to claim 1, further comprising (c ′) powdered sulfur.
The lubricating oil composition for metal working according to claim 1 or 2, wherein the base oil as component (a) contains mineral oil, or one or more selected from mineral oil and ester synthetic oil and polymethacrylate.
The lubricating oil composition for metal working according to claim 3, wherein the ester synthetic oil is an ester of a polyhydric alcohol having 2 to 6 carbon atoms and an aliphatic acid having 2 to 24 carbon atoms.
5. The lubricating oil composition for metal processing according to claim 1, wherein the metal sulfonate as component (b) is an overbased alkaline earth metal sulfonate.
6. The lubricating oil composition for metal working according to claim 1, wherein the content of sulfur in the active polysulfide as the component (c) is 20% by mass or more.
The metal according to any one of claims 1 to 6, wherein the fatty acid partial ester of the polyhydric alcohol as component (d) is a partial ester of a polyhydric alcohol having 2 to 6 carbon atoms and a fatty acid having 6 to 24 carbon atoms. Lubricating oil composition for processing.
The lubricating oil composition for metal working according to any one of claims 1 to 7, wherein the nonionic surfactant as the component (e) is a polyoxyalkylene type nonionic surfactant.
The lubricating oil composition for metal working according to claim 8, wherein the polyoxyalkylene type nonionic surfactant has a polyoxyethylene group and a polyoxypropylene group.
(B) 1% by mass to 20% by mass of metal sulfonate, (c) 2% by mass to 25% by mass of active polysulfide, (c ′) 3% by mass of powder sulfur, d) a fatty acid partial ester of a polyhydric alcohol of 1 to 20% by mass and (e) a nonionic surfactant of 2 to 25% by mass. Lubricating oil composition for metal working.
The lubricating oil composition for metal working according to any one of claims 1 to 10, which is used for steel pipe expansion processing.