Hot-rolling oil composition for steel

Abstract

To provide a hot-rolling oil composition exhibiting excellent lubricity at a high temperature, capable of greatly reducing a friction coefficient between a roll and a rolled material when oil is supplied by a water-injection method, an air-spray method, or a direct coating method to both or one of the roll and the rolled material, in hot rolling of steel or special steel performed in a high temperature region.SOLUTION: A hot-rolling oil composition for steel includes (A) 35 to 80 mass% of paraffinic mineral oil of a kinetic viscosity of 100 to 700 mm2 / s, (B) 15 to 60 mass% of vegetable oil, and (C) 1 to 20 mass% of a sulfur based extreme pressure agent, based on the total mass of the composition, and has a kinetic viscosity at 40°C of 50 to 300 mm2 / s.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an inexpensive hot-rolling oil composition mainly composed of mineral oil, which has excellent lubricating properties and can significantly reduce the coefficient of friction between rolls and rolled materials during hot rolling of steel or special steel. [Background technology]

[0002] In hot rolling of steel or special steel, hot rolling oil compositions (sometimes called oil compositions) are used to reduce the coefficient of friction between the roll and the rolled material, and are effective. As the rolling oil, at least one of solid lubricants such as graphite, water glass, boron nitride, mica, molybdenum disulfide, iron oxide, calcium carbonate, and fluorinated graphite, which have a lubricating effect at high temperatures; extreme pressure agents such as sulfurized oils and fats, sulfurized olefins, zinc dialkyl dithiophosphate, and phosphate esters; oiliness improvers such as mineral oils, oils and fats, oil polymers, and synthetic esters; adhesion improvers and pour point depressants such as methacrylate copolymers and butylene butadiene copolymers, or an antioxidant (di-tertiary butyl cresol, alpha naphthylamine, di-tertiary butyl phenol, etc.) is generally used (Patent Document 1). Although the above-mentioned solid lubricants, extreme pressure agents and oiliness improvers are effective in reducing the coefficient of friction between the roll and the rolled material, they are often expensive. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3320642 Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, an object of the present invention is to provide an inexpensive hot-rolling oil composition which has good lubricating properties at high temperatures and can significantly reduce the coefficient of friction between a roll and a rolled material when the oil is supplied to both or either of the roll and the rolled material by a water injection method, an air spray method, or direct application in hot rolling of steel or special steel carried out in a high temperature region. [Means for solving the problem]

[0005] 1. Based on the total weight of the composition, (A) 35 to 80 mass% kinematic viscosity 100 to 700 mm 2 / s paraffinic mineral oils, (B) 15 to 60 mass% vegetable oil, (C) 1 to 20 mass% of a sulfur-based extreme pressure agent, Including, Kinematic viscosity at 40℃ is 50 to 300mm 2 A hot rolling oil composition for steel products, comprising: 2. The hot-rolling oil composition for steel products according to the above 1, wherein (B) the vegetable oil is a mixed oil containing at least 45 mass% of rapeseed oil. 3. The hot rolling oil composition for steel products according to 1 or 2 above, wherein the sulfur-based extreme pressure agent (C) is a sulfurized oil having a sulfur content of 10 mass % or more. 4. A method for hot rolling a steel material, comprising supplying the hot rolling oil composition for steel material according to any one of items 1 to 3 above to at least one of a work roll and a backup roll of a rolling mill for rolling the steel material by a water injection method. Effect of the Invention

[0006] The hot-rolling oil composition for steel products of the present invention is more effective in reducing the friction coefficient at high temperatures than conventional hot-rolling oils. The hot-rolling oil composition of the present invention also has excellent adhesion to metal surfaces, making it easier to obtain the effects when used in an actual machine. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] (A) Kinematic viscosity at 40°C is 100 to 700 mm 2 / s Paraffinic mineral oil The kinetic viscosity of the component (A) of the present invention at 40°C is 100 to 700 mm 2 / s, preferably 300 to 600 mm 2 / s, and more preferably 350 to 500 mm 2 By setting the kinetic viscosity at 40°C in this range, the kinetic viscosity at 40°C of the entire composition is set to 50 to 300 mm 2 / s. Paraffinic mineral oils have better lubricity at high temperatures than naphthenic mineral oils. The %CP by ring analysis (ndM method) is preferably 50 or more, more preferably 55 or more, even more preferably 60 or more, and preferably 90 or less, more preferably 85 or less. By using paraffinic mineral oils having such a %CP, the lubricity is improved. From the viewpoint of lubricity and the kinetic viscosity at 40°C of the entire composition, the component (A) is preferably a kinetic viscosity at 40°C of 350 to 500 mm 2 Paraffinic mineral oils having a viscosity of 100 / s and a % CP of 60 to 85 are particularly preferred. The mass ratio of component (A) is 35 to 80 mass%, preferably 42 to 80 mass%, and more preferably 45 to 80 mass% based on the total mass of the composition. By including component (A) in such a ratio, the lubricity is further improved and the cost is reduced.

[0008] (B) Vegetable oil Component (B) of the present invention includes vegetable oils such as rapeseed oil, soybean oil, rice oil, castor seed oil, coconut oil, palm oil, palm olein oil, and mixtures thereof. From the viewpoints of lubricity and economy, the component (B) of the present invention is preferably rapeseed oil, soybean oil, rice oil, palm olein oil, or a mixture thereof. A mixed oil containing at least 45% by mass of rapeseed oil based on the total mass of the component (B) is more preferred. A mixed oil containing at least 45% by mass of rapeseed oil and at least 25% by mass of soybean oil based on the total mass of the component (B) is even more preferred. A mixed oil of rapeseed oil, soybean oil, palm olein oil, and other vegetable oils such as rice oil is particularly preferred. In particular, a mixed oil of 40 to 60% by mass of rapeseed oil, 20 to 45% by mass of soybean oil, 1 to 15% by mass of palm olein oil, and the remainder of other vegetable oils such as rice oil based on the total mass of the component (B) is preferred. The mass ratio of component (B) is 15 to 60 mass%, preferably 15 to 55 mass%, and more preferably 15 to 50 mass% based on the total mass of the composition. By including component (B) in such a ratio, the lubricity is further improved.

[0009] (C) Sulfur-based extreme pressure agents Examples of the sulfur-based extreme pressure agent (C) of the present invention include sulfur-based compounds such as sulfurized oils and fats, sulfurized olefins, polysulfides, and mixtures thereof. The sulfurized oils and fats that can be used in the present invention are also called sulfurized esters, and refer to fatty acid glycerol esters and sulfides of fatty acid esters. From the viewpoint of lubricity, the sulfurized oils and fats used in the present invention preferably have a sulfur content of 5% by mass or more, more preferably 7% by mass or more, and preferably 20% by mass or less. The sulfur content can be measured according to JIS K 2541-3. Representative compounds are represented by the following formula (1) or (2) (wherein R is a hydrocarbon group, and x is a number of 1 or more). The sulfurized oil may be synthesized by a known method or may be a commercially available product. Examples of commercially available sulfurized oils include MAYSPERM 2011LV (Dover Chemical Co.), DAILUBE FS-150 (DIC Corporation), DAILUBE S-290 (DIC Corporation), DAILUBE S-310KD (DIC Corporation), DAILUBE GS-110 (DIC Corporation), and DAILUBE S-285 (DIC Corporation).

[0010] The sulfurized olefins that can be used in the present invention can be represented by the following formula: R 1 S-(Sx-R 2 -Sy)nR 1 (In the formula, x represents an integer of 0, 1, or 2, y represents an integer of 1 to 3, n represents an integer of 1 to 10, and R 1 and R 2 each independently represents a saturated or unsaturated hydrocarbon group having 4 to 10 carbon atoms. The sulfurized olefin may be synthesized by a known method or may be a commercially available product, such as ANGLAMOL33 (Lubrizol Japan Co., Ltd.), NA-LUBE EP-5120 (KING INDUSTRIES Co., Ltd.), NA-LUBE EP-5130LC (KING INDUSTRIES Co., Ltd.), NA-LUBE EP-5415 (KING INDUSTRIES Co., Ltd.), DAILUBE GS-420 (DIC Co., Ltd.), DAILUBE GS-440LS (DIC Co., Ltd.), and ADDITIN RC2540 (Lanxess Co., Ltd.).

[0011] The polysulfide that can be used in the present invention refers to a compound represented by the general formula R-Sn-R' (wherein R and R' may be the same or different and represent a hydrocarbon group such as a linear or branched alkyl group (the alkyl group may be substituted with an aromatic ring such as a phenyl group, a cycloalkane such as a cyclohexyl group, and / or may contain a heteroatom such as sulfur in the chain); n is a number of 2 or more). Note that when it is an olefin sulfide, the sulfide is a mixture and is called a sulfurized olefin, and when the sulfide is a single substance, it is sometimes called a polysulfide to distinguish it from the polysulfide. However, in this specification, no distinction is made between the two depending on whether the sulfide is a mixture or a single substance, and the sulfurized olefin is treated as a subordinate concept of polysulfide. Representative polysulfides are represented by the following formulas (3) to (6) (wherein R is a hydrocarbon group). The polysulfide may be synthesized by a known method or may be a commercially available product. Examples of commercially available polysulfides include TPS-20, -32, and -44 (Arkema Co., Ltd.).

[0012] [ka]

[0013] From the viewpoints of effectiveness and economy, sulfurized oils and fats are particularly preferred as the component (C) used in the present invention. In particular, sulfurized oils and fats having a sulfur content of preferably 7% by mass or more are preferred. Particularly preferred are sulfurized oils and fats having a sulfur content of 7 to 20% by mass. The mass ratio of component (C) is 1 to 20 mass%, preferably 3 to 15 mass%, and more preferably 5 to 10 mass%, based on the total mass of the composition. By including component (C) in such a ratio, good lubricity is achieved. The composition of the present invention has a kinetic viscosity of 50 to 300 mm at 40°C. 2 This provides good adhesion. The preferred range is 80 to 275 mm. 2 / s, more preferably 90 to 250 mm 2 / s. 50mm 2At less than 300 mm / s, the amount of adhesion to the work roll and backup roll surfaces will be small, and the effect may not be fully obtained. 2 If the oil flow rate exceeds 1 / s, the resistance to flow through the piping increases, and if the piping for the rolling oil is narrow, it may become difficult to pump the rolling oil.

[0014] [Optional ingredients] In the present invention, as long as the effects of the present invention are not impaired, additives that are usually used in hot rolling oil compositions for steel products, such as antioxidants, oiliness agents, pour point depressants, adhesion improvers, etc., can be added as necessary. The total content of these components is usually about 0.1 to 4 mass%, preferably 0.5 to 4 mass%, based on the total mass of the composition. [Antioxidants] Antioxidants are known as agents for suppressing oxidation deterioration of hot rolling oil. Antioxidants that can be used in the present invention include phenol-based antioxidants and amine-based antioxidants. Examples of phenol-based antioxidants include 2,6-di-tertiary butyl-p-cresol (BHT), 2,2'-methylene bis(4-methyl-6-tertiary butylphenol), 4,4'-butylidene bis(3-methyl-6-tertiary butylphenol), 2,6-di-tertiary butyl-phenol, 2,4-dimethyl-6-tertiary butylphenol, tertiary butyl hydroxyanisole (BHA), 4,4'-butylidene bis(3-methyl-6-tertiary butylphenol), 4,4'-methylene bis(2,3-di-tertiary butylphenol), and 4,4'-thiobis(3-methyl-6-tertiary butylphenol). Examples of the amine-based antioxidants include Nn-butyl-p-aminophenol, 4,4'-tetramethyl-di-aminodiphenylmethane, α-naphthylamine, N-phenyl-α-naphthylamine, and phenothiazine. As the antioxidant used in the present invention, from the viewpoint of economy, N-phenyl-α-naphthylamine and 2,6-di-tertiarybutyl-p-cresol (BHT) are preferred. When the composition of the present invention contains an antioxidant, the content thereof is preferably 0.05 to 4 mass %, and more preferably 0.5 to 2 mass %, based on the total amount of the composition, from the viewpoints of effectiveness and economy. [Oil-based agent] The composition of the present invention may further contain an oily agent. Examples of oily agents that can be used in the composition of the present invention include higher fatty acids, higher alcohols, fats and oils, esters, etc. From the viewpoint of lubricity, fats and oils and esters are preferred. When the composition of the present invention contains an oily agent, the content thereof is preferably 0.5 to 4 mass %, and more preferably 1 to 3 mass %, based on the total amount of the composition, from the viewpoints of effectiveness and economy.

[0015] The hot rolling oil composition for steel products of the present invention includes: (A) Kinematic viscosity at 40°C is 100 to 700 mm 2 45 to 80 mass% of paraffinic mineral oil having a molecular weight of 1000 to 15000; (B) a mixed oil containing at least 45% by mass of rapeseed oil, and (C) 5 to 10% by mass of sulfurized oil and fat; or consisting of these components, and having a kinetic viscosity of 50 to 300 mm at 40°C 2 Particularly preferred are compositions in which

[0016] The hot rolling oil composition for steel products of the present invention includes: (A) Kinematic viscosity at 40°C is 300 to 600 mm 2 / s and a %CP of 55 to 90, (B) 15 to 50% by mass of a mixed oil containing at least 45% by mass of rapeseed oil and at least 25% by mass of soybean oil, and (C) 5 to 10% by mass of sulfurized oil or fat having a sulfur content of preferably 5% by mass or more, or consisting of these components, and having a kinetic viscosity of 80 to 275 mm at 40°C. 2 Also especially preferred are compositions in which

[0017] The hot rolling oil composition for steel products of the present invention includes: (A) Kinematic viscosity at 40°C is 350 to 500 mm 2 / s and a %CP of 60 to 85, (B) 15 to 50% by mass of a vegetable oil containing 40 to 60% by mass of rapeseed oil, 20 to 45% by mass of soybean oil, 1 to 15% by mass of palm olein oil, and the remainder being rice oil; (C) 5 to 10% by mass of sulfurized oil or fat having a sulfur content of 7 to 20% by mass, or consisting of these components, and having a kinetic viscosity of 90 to 250 mm at 40°C. 2 Also especially preferred are compositions in which

[0018] The hot rolling oil composition of the present invention can be easily produced by mixing and dissolving the components (A) to (C) and, if necessary, any optional components under appropriate temperature conditions, for example, at about 40 to 70°C. The hot-rolling oil composition of the present invention can be used by diluting it with water to about 0.1 to 5.0 mass % and supplying it to at least one of the upper and lower work rolls and the backup roll of a rolling mill for rolling steel materials (including special steels). The amount of oil supplied to the work roll varies depending on the rolling conditions, but the amount of the hot rolling oil composition (stock solution) of the present invention is preferably 0.3 g / m 2 More preferably, 0.5 to 3.0 g / m 2 0.3g / m 2 If the amount is less than 5.0 g / m, the effect may not be sufficient. 2 If the rolling load exceeds this limit, the amount of rolling oil adhering to the roll surface will increase significantly and the rolling load will be excessively reduced, causing slippage between the roll and the rolled material, which may make normal rolling impossible. The amount of material supplied to the backup roll varies depending on the rolling conditions, but is preferably 0.5 g / m 2 More preferably, 1.0 to 5.0 g / m 2 0.5g / m 2 If the amount is less than 10.0 g / m, the effect may not be sufficient. 2In the above cases, as with work roll oiling, slippage may occur between the rolls and the rolled material, making normal rolling impossible. The hot-rolling oil of the present invention can be supplied by a water injection method using water as an injection medium, an air spray method in which air and rolling oil are mixed and sprayed, an airless spray method in which rolling oil is airlessly sprayed using a high-pressure plunger pump, or a premix method. Of these methods, the water injection method is preferred. EXAMPLES

[0019] Hot rolling oil compositions were prepared by mixing the components shown below in the mass ratios shown in Tables 1 and 2. The properties of these compositions were evaluated by the following methods. The results are shown in Tables 1 and 2.

[0020] (A) Paraffinic mineral oil Paraffinic mineral oil (dynamic viscosity @ 40℃: 640mm 2 / s,%CP:69) Paraffinic mineral oil (dynamic viscosity @ 40℃: 440mm 2 / s,%CP:68) Paraffinic mineral oil (dynamic viscosity @ 40℃: 360mm 2 / s,%CP:71) Paraffinic mineral oil (dynamic viscosity @ 40℃: 300mm 2 / s, %CP:70) Paraffinic mineral oil (dynamic viscosity @ 40℃: 100mm 2 / s,%CP:68) Naphthenic mineral oil (kinematic viscosity @40℃: 440mm 2 / s, %CP:44, for comparison) (B) Vegetable oil Rapeseed oil Mixed oil (approximately 50% rapeseed oil, 30-40% soybean oil, the rest being other vegetable oils (rice oil, etc.)) soybean oil Palm Olein Oil (C) Sulfur-based extreme pressure agents Sulfurized oil 1 (sulfur content: 10% by mass) Sulfurized oil and fat 2 (sulfur content: 11.5% by mass) Sulfurized Olefins Polysulfide

[0021] (1)Kinematic viscosity Measured according to JIS K 2283. [Evaluation Criteria] ○: The 40°C kinematic viscosity of the entire composition is 50 to 300 mm 2 / s ×: The 40°C kinetic viscosity of the entire composition is 50mm 2 / s or more than 300 mm 2 / s

[0022] (2) High temperature lubrication properties (friction coefficient) The high temperature lubricating properties of the rolling oil composition of the present invention were evaluated by the friction coefficient when a rotating roll was pressed at 30 kN against a steel material fixed to a rolling mill and heated to 900°C. [Test conditions] Testing machine E-12 type hot rolling mill Rolled high speed steel (124mmφ×80mm) Roll speed: 0.65m / s (100rpm) Fixed steel material SS-400 (20mm x 20mm x 580mm) Fixed steel temperature 900℃ (5V 4000A induction heating) Load 30kN (hydraulic pressure) Oiling: Neat oil brushed on Test time: 10s [Evaluation Criteria] ○: Friction coefficient is 0.08 or less ×: Friction coefficient exceeds 0.08

[0023] (3) Adhesion test (amount of adhesion) The hot rolling oil composition was diluted with water to 0.5% and sprayed onto the degreased and cleaned surface of a steel sheet using a spray nozzle, and the amount of the oil adhering to the steel sheet surface after drying was measured by a gravimetric method. [Test conditions] Dilution water temperature: 25℃ Hot rolling oil composition concentration: 0.5% Spray nozzle: 1 / 4KSH-0480 (Kyoritsu Alloy Manufacturing Co., Ltd.) Distance between steel plate and spray nozzle: 300mm Injection pressure: 0.3MPa Spray time: 2 seconds Steel plate: SPCC-SD 100×100×0.8mm Steel plate temperature: room temperature Drying conditions: Place in an 80°C air oven for 10 minutes [Evaluation Criteria] ○: Adhesion amount 21.5g / m 2 End ×: Adhesion amount 21.5g / m 2 less than

[0024] comprehensive evaluation ○: All ratings are ○ ×: × in any evaluation

[0025] [Table 1]

[0026] [Table 2]

Claims

1. Based on the total weight of the composition, (A) 35 to 80% by mass kinematic viscosity 100 to 700 mm 2 / s, a paraffinic mineral oil; (B) 15 to 60% by mass of a vegetable oil; (C) 1 to 20 mass % of a sulfur-based extreme pressure agent, Including, Kinematic viscosity at 40°C is 50 to 300 mm 2 A hot rolling oil composition for steel products,

2. 2. The hot-rolling oil composition for steel products according to claim 1, wherein the vegetable oil (B) is a mixed oil containing at least 45 mass% of rapeseed oil.

3. The hot rolling oil composition for steel products according to claim 1, wherein the sulfur-based extreme pressure agent (C) is a sulfurized oil having a sulfur content of 10 mass% or more.

4. 4. A method for hot rolling a steel material, comprising: supplying the hot rolling oil composition for steel material according to any one of claims 1 to 3 to at least one of a work roll and a backup roll of a rolling mill for rolling the steel material by a water injection method.

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