JP2003003187A - Hot rolling oil composition for stainless steel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot rolling oil composition having high scorch resistance enough to be applicable to the hot rolling of stainless steel needing high scorch resistance. SOLUTION: This hot rolling oil composition is obtained by incorporating a base oil consisting of at least one of mineral oil, oil and fat and synthetic ester with 40-90 mass%, based on the whole composition, of an ester sulfide >=10 mass% in sulfur content and/or a polysulfide and a cationic surfactant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot rolling oil composition, which prevents seizure of a rolled material and a work roll during hot rolling of stainless steel, suppresses roughening of the roll, and causes friction between the rolled material and the work roll. The hot rolling oil composition is capable of maintaining a high coefficient and ensuring stable biting of a rolled material.

[0002]

2. Description of the Related Art Conventionally, as hot rolling oil, fats, fatty acids,
Synthetic esters, mineral oils and the like are used and applied to backup rolls and work rolls by a water injection method, and have been applied for the purpose of reducing rolling load, suppressing roll wear, or preventing roll roughening. However, in the case of stainless steel, the surface oxide scale generated during hot rolling is extremely thin compared to ordinary steel, so contact between the rolling roll and the metal easily occurs, seizure occurs, and roll surface roughness occurs. A flaw of the rolled material is likely to occur, and a product in which the flaw is generated needs to be subjected to pickling and polishing twice or more after hot rolling, resulting in a problem of high cost. Further, in order to remove the above-mentioned seizure, it is necessary to grind a large amount of rolls, which causes a problem that the roll unit is deteriorated.

The conventional hot rolling oil cannot cope with these problems, and there is a strong demand for a hot rolling oil capable of preventing seizure, and the refueling method is a heat injection method which can use the water injection method which has been conventionally used. Hot rolling oil was sought.

The "iron oxide powder + a viscous aqueous solution of calcium carbonate" proposed in Japanese Patent Laid-Open No. 6-136381 requires an oil supply device of a system different from the conventionally used water injection system. Although the water injection method can be applied to the "iron oxide powder + polymer compound" proposed in Japanese Patent Publication No. 6-62980, stable supply such as precipitation separation is difficult because both are powder dispersions. Requires mixed maintenance and was not very effective.

The rolling oil proposed by Japanese Patent Laid-Open No. 5-179276 has a seizure resistance effect due to polysulfide in warm rolling (150 to 400 ° C.), but since it has a high friction coefficient, it is used in combination with a phosphite ester. ing.
When this was actually used for hot rolling, the coefficient of friction was too low, and as a result, the biting property of the rolled material into the roll was reduced, and therefore it could not be used. On the other hand, in order to solve the above-mentioned problems, the present inventor discloses in JP-A-2000-178575 and JP-A-2000-230187 that a sulfur content is 10% by mass or more and a sulfur content is 20 or more.
A hot rolling oil composition was proposed in which polysulfides were contained individually or both by mass%. These hot rolling oils show excellent seizure resistance in the rolling of stainless steel, but from the recent needs for further productivity improvement,
In the case of high pressure rolling or high speed rolling, it was not sufficient in terms of preventing seizure of the roll.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hot rolling oil having high seizure resistance which can be applied to hot rolling of stainless steel which requires high seizure resistance.

[0007]

The present invention has been made to solve the above problems. Usually, the hot rolling oil of the actual equipment is generally fed to the backup roll or the work roll by the water injection method, but in this lubrication method, the effect of adhesion to the roll is increased and stainless steel hot rolling is performed. As a result of further research for the purpose of improving the seizure prevention effect at the time, one or more base oils of mineral oil, fats and oils, and synthetic esters were sulfurized with a sulfur content of 10% by mass or more based on the entire composition. 0.05 to 1.5 of a cationic surfactant (also simply referred to as a cationic surfactant) is added to a hot rolling oil containing 40 to 90% by mass of polysulfide having an ester and / or sulfur content of 10% by mass or more. Addition by mass% increases the anti-emulsification property of the hot rolling oil, that is, by means of decreasing the emulsification dispersibility, it is added by water injection lubrication. The amount greatly increased, further obtain a knowledge that can improve the anti-seizing effect of stainless steel during hot rolling, has led to the development of hot-rolling oil that can solve the above problems.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Although the action of the cationic surfactant used in the present invention is not clear, it has the action of aggregating oil droplets dispersed in water when water injection oiling is performed, increasing the size of oil droplets, As a result, it is considered that the effect of increasing the amount of adhesion to the roll is exhibited. The cationic surfactant used here is a mineral oil that is a base oil, is soluble in any of fats and oils and synthetic esters, and is also selected to be soluble in sulfurized esters and polysulfides,
Add to these base oils, dissolve and use. The amount to be added to this base oil is 0.05 to 1.5% by mass,
If it is less than 5% by mass, the amount adhered to the roll does not change,
If it is added in an amount of more than 1.5% by mass, the stability of the undiluted solution becomes poor, and the dispersion stability of the mixing solution by the water injection method becomes poor, resulting in a lack of stable coating property. Examples of the cationic surfactant include amine salt types such as octadecylamine acetate, tetradecylamine acetate, tallow alkyl propylene diamine acetate, and ammonium chloride types such as octadecyltrimethylammonium chloride and dodecyltrimethylammonium chloride. , Alkyldimethylbenzylammonium chloride, tetradecyldimethylbenzylammonium chloride and the like, imidazoline type hydroxyethylalkylimidazoline chloride and pyridine type alkylpyridinium chloride, alkylpyridinium bromide and the like, and quinoline type alkylisoquinolium bromide. And alkyl quinolium chloride. The base oil is the mineral oil disclosed in JP-A-2000-178575,
Hot rolling oil containing 60 to 90% by mass of polysulfide having a sulfur content of 20% by mass or more in fats and oils and synthetic esters, and sulfur content of 10% by mass in mineral oil, fats and oils and synthetic esters disclosed in JP-A-2000-230187. Any of the hot rolling oils containing 40 to 90% by mass of the above sulfurized ester can be applied. Examples of the sulfurized ester include sulfurized lard containing 10 mass% or more of S content, sulfurized olefins, fats and oils having unsaturated fatty acids such as sulfurized rapeseed oil, simple sulfides of esters and olefins, and composites thereof.
More specifically, sulfurized low melting point lard, sulfurized soybean oil methyl ester, sulfurized sperm oil, sulfurized soybean oil, sulfurized bran oil, sulfurized chicken oil, and sulfurized olefin can be exemplified.

Examples of the polysulfide used in the present invention include dialkyl polysulfides such as didodecyl polysulfide and dihexyl polysulfide containing 20 mass% or more of S. As the alkyl at this time, those having 6 to 15 carbon atoms can also be used.

Mineral oil which is a base oil used in the present invention,
Oils and fats and synthetic esters have been conventionally used in this type of rolling oil composition, and various kinds of oils and fats are widely used. For example, the representative examples are as follows.

As the mineral oil, for example, spindle oil, machine oil, motor oil, cylinder oil, etc. of 10 to 900 mm ²
/ S viscosity (40 ° C.).

The fats and oils include, for example, beef tallow, lard, palm oil, coconut oil, rapeseed oil, soybean oil and the like.

The synthetic ester is usually an ester synthesized from a fatty acid and an alcohol, the fatty acid is a C ₁₂ -C ₃₆ monobasic acid or a dibasic acid, and the alcohol is a C ₁ -C ₁₈ monobasic acid. Examples include polyhydric or polyhydric alcohols.

Specific examples thereof include ethylhexyl palmitate, butyl oleate, butyl carbitol isostearate, lauryl behenate, neopentyl glycol oleate, trimethylolpropane laurate, trimethylolpropane isostearate. , Pentaerythritol oleic acid ester, trimethylolpropane dimer acid ester and the like.

The rolled material used when the composition of the present invention is used includes stainless steel, and can be widely used for various grades of stainless steel. For example, martensitic stainless steel represented by SUS403 (13 chrome stainless steel),
Austenitic stainless steel typified by SUS304 (nickel, chrome type), Ferritic stainless steel typified by SUS430 (18 chrome type), SUS444
Examples include high-purity ferritic stainless steel such as SUS434 and SUS329 duplex stainless steel.

The hot rolling oil of the present invention is a method for supplying oil to a backup roll or a work roll by a water injection method which is usually applied in hot rolling, and the effect of adhering to the roll is greatly enhanced, and stainless steel is used. Enhances the seizure prevention effect during hot rolling.

[0017]

EXAMPLES Examples and comparative examples are shown below to facilitate understanding of the present invention.

[0018]

[Examples 1 to 8] The hot rolling oil compositions of the present invention were produced by mixing the predetermined components shown in Table 1 below in predetermined amounts.

[0019]

[Comparative Examples 1 to 4] The hot rolling oil compositions for Comparative Examples were produced by mixing the predetermined components shown in Table 2 below in predetermined amounts.

With respect to the compositions of Examples 1 to 8 and Comparative Examples 1 to 4 described above, separability (anti-emulsification property) after emulsification and dispersion by a homomixer, adhesion amount by an adhesion tester, and baking resistance by a hot Timken test The adhesion test and the coefficient of friction were measured.
However, the test method is as follows.

(Test 1) Separate measurement after emulsification and dispersion with a homomixer. 1 shows a test apparatus, in which (a) is for explaining when emulsified and dispersed, and (b) is for explaining when observing the separated oil component. <Conditions> Mixing liquid 400 ml (500 ml beaker) Concentration 3% (water = 388 ml, oil = 12 ml) Water temperature 30 ° C Stirring conditions 10,000 rpm x 10 min <Method and judgment> Mixing liquid 400 ml with the device shown in FIG. After stirring at 10,000 rpm for 10 minutes, the mixture is allowed to stand in a beaker, and after 3 minutes, the separation state of the oil component is observed and judged by the separability. However, in FIG. 1, 1 is a homomixer, 2 is a beaker, and 3 is a mixing liquid (oil + water). ⊚: Very good separability ○: Good separability Δ: Slightly separable ×: Slightly separable XX: Not separable at all (Test 2) Adhesion measurement by an adhesion tester. FIG. 2 shows the test apparatus. However, in FIG. 2, 4 is a mixing device, 5 is a spray nozzle, 6 is a rolling oil pump, 7 is a rolling oil tank, 8 is a water pump, 9 is a water tank, and 10 is a test piece (SPCC-SD). ), 11 shows a pressure gauge. <Conditions> Nozzle full cone nozzle KSF0365
(Made by Everloy) Lubrication rate 40 ml / min Application pressure 0.3 MPa (Concentration) (0.67%) Water temperature 30 ° C Application time 5 sec <Method and judgment> SPCC-SD with the device shown in FIG.
(100 × 100 × 0.8 mm) is spray-coated, and after removing water with an air gun, it is drained for 24 hours and the amount of adhered oil is measured. (Test 3) Seizure resistance test and friction coefficient measurement by hot Chimken test. However, the test equipment is shown in FIG. <Seizure resistance test> Specimen: SUS-444 Specimen temperature: 900 ° C Roll: HSS Roll speed: 600 rpm Load: Raise 49N every 2 minutes to increase the load until seizure. (Max490N) Refueling method: Water injection, 150ml /
min Lubrication rate: 3 ml / min <Method and Judgment> 1 test piece of 12 test pieces in the apparatus shown in FIG.
It was heated by the high frequency heating coil of 3 and the temperature was measured and recorded by the thermocouple of 17, and 14 rolls and 12 heated test pieces were in contact with each other. , 16 air draining is performed and the maximum load until baking in a hot state is measured.

<Friction Coefficient Measurement Test> Specimen: SUS-304 Specimen temperature: 900 ° C. Roll: HSS Roll speed: 150 rpm Load: 392N Lubrication method: Water injection, 150 ml /
min Lubrication amount: 3 ml / min Friction coefficient: Torque / load / roll radius <Method and Judgment> Twelve test pieces were tested by the device shown in FIG.
It was heated by the high frequency heating coil of 3 and the temperature was measured and recorded by the thermocouple of 17. When 14 rolls and 12 heated test pieces were in contact and a load of 392N was applied, 1
Oil is supplied from water injection 5 and air draining 16 is performed, and the friction coefficient is measured by measuring the torque.

[0023]

[Table 1]

[0024]

[Table 2]

However, the components used in Tables 1 and 2 are as follows. Sulfurized ester 1: Active type Sulfurized lard (S = 15% by mass) Sulfurized ester 2: Complex sulfurized ester (S = 30% by mass) Polysulfide: Ditershade decyl polysulfide (S = 32% by mass) Cationic activator 1: Octadecylamine acetic acid Salt cation activator 2: Octadecyl trimethyl ammonium chloride synthetic ester: pentaerythritol oleic acid full ester oil / fat: liquid lard fatty acid: oleic acid mineral oil: motor oil (viscosity 150 mm ² / s, / 40 ° C)

The following can be clearly understood from the above Tables 1 and 2. 1. The addition of the cationic surfactant improved the separability of the rolling oil after emulsification and dispersion, and all Examples 1 to 8 had good separability. For this reason, the adhesiveness in water injection coating was also good, and the amount of adhesion was significantly increased as compared with Comparative Examples 1 and 2. 2. As a result of simulating the lubrication state of hot rolling and measuring the seizure resistance load of stainless steel (SUS444) during hot rolling, Comparative Examples 1 and 2 seize at 147N to 196N, but Examples 1 to 8 Addition of 50 to 80% by mass of sulfurized ester and polysulfide worked effectively because the amount of adhesion increased, and it did not seize up to 392 N or more, and did not seize up to 490 N in case of adding 80% by mass and 0.5% by mass of cationic surfactant. , Showed significantly higher seizure resistance. In Comparative Examples 3 and 4 in which the cationic surfactant was added to the synthetic ester and fats and oils, the separability after emulsification and dispersion was improved, and the adhesion amount was significantly increased, but seizure occurred at 49N. 3. Similarly, as a result of measuring the friction coefficient with hot Chimken, Examples 1 to 8 are 0.12 or more, and even if the adhesion amount is increased as compared with Comparative Examples 3 and 4, the addition oils of sulfurized ester and polysulfide are Since the coefficient of friction is slightly higher than that of synthetic esters and oils and fats that are usually applied in hot rolling of ordinary steel, it is judged that there is no problem such as slip when the rolled material bites into the roll in actual rolling, and the stripability is good. The hot rolling oil for the purpose of reducing the load and the friction coefficient of ordinary steel has a friction coefficient of 0.08-0.10 in this hot Timken test, and Examples 1-8 of the present invention have a friction coefficient of 0.12 or more. Therefore, the stripability is good in the actual hot rolling. 4. In Comparative Examples 1 and 2, since the amount of adhesion is small, the seizure resistance load is 147N to 196N, which is lower than that of the Examples, and the effects of the sulfurized ester and polysulfide are not sufficiently exhibited. Further, in Comparative Examples 3 and 4, the amount of adhesion is large due to the cationic surfactant, but the seizure resistance load is only 49 N, and it is not effective in preventing seizure of stainless steel. Comparative Example 3
Since Nos. 4 and 4 show a decrease in friction coefficient of 0.09, it is difficult to apply them to actual machines. In comparison with them, in Examples 1 to 8, since the sulfurized ester and / or polysulfide and the cationic surfactant were added to the composition, the adhesion amount was 3.5 to 5.9 g / m ² . Significantly increased, the seizure resistance is as high as 392 N or more, and the hot rolling oil obtained by adding a cationic surfactant to the base oil of sulfurized ester and / or polysulfide has an excellent anti-seizure property of stainless steel. In addition, since the friction coefficient is 0.12 or more, it is judged that it can be stably applied to the actual hot rolling oil.

Further, Examples 1, 2, 4 to 7 and Comparative Examples 1 to 1
Seizure resistance by hot rolling tester for each of 3
The skin roughness and the coefficient of friction were measured by the following method using the apparatus shown in FIG. The results are shown in Table 3 (Examples) and Table 4
(Comparative example).

However, in FIG. 4, 18 is a work roll (a is an upper roll, b is a lower roll), 19 is a mixing device, 20 is a spray nozzle, 21 is a gear pump, 22
Is a water tank, 23 is a water pump, 24 is a rolling oil tank, 25 is a rolling oil pump, and 26 is a rolled material (strip).

(Test 4) A seizure resistance / rough skin test and a friction coefficient measurement using a hot rolling tester. <Seizure resistance / rough skin test> Rolled material: SUS-444 equivalent C = 0.003 mass%, Cr = 18.5 mass% Mo = 2.0 mass%, Ti = 0.2 mass%, balance Fe Dimension: thickness 15 × width 100 × length 500 mm Heating temperature: 900 ° C. Rolling: 15 mm → rolling from 7 mm in 4 passes Roll diameter: 200 mm (barrel length 200 mm) Roll roughness: 1.0 μm Ra Refueling method: Water injection rolling oil: 30 mL / min Hot water (40 ° C.): 3 L / min Evaluation: Anti-seizure / roughness was evaluated by the ratio of the seizure area on the surface of the rolled material after rolling. ◎: No seizure ○: Seizure area 5% or less △: Seizure area 20% or less △ ×: Seizure area 50% ×: 100% seizure

<Measurement of hot friction coefficient> Rolled material: SUS-444 equivalent C = 0.003 mass%, Cr = 18.5 mass% Mo = 2.0 mass%, Ti = 0.2 mass%, balance Fe And SUS-304 dimensions: thickness 15 x width 100 x length 50
0 mm Heating temperature: 1000 ° C. Rolling: Rolling at a rolling ratio capable of biting (1 pass rolling) Roll diameter: 200 mm (barrel length 200 mm) Roll roughness: 1.0 μm Ra Oil supply method: Water injection method Rolling oil: 30 mL / min Hot water (40 ° C.): 3 L / min Evaluation: In order to evaluate the biting property, the biting friction coefficient was calculated by μ = tan (θ) using the biting angle θ at which rolling was possible. FIG. 5 shows the biting angle θ. However, FIG.
Indicates the same as in FIG.

[0031]

[Table 3]

[0032]

[Table 4]

The following can be clearly understood from Tables 3 and 4. (1) Simulate the lubrication state of hot rolling, and the seizure resistance and surface roughening resistance of stainless steel (SUS-444) in hot rolling are performed under the above-mentioned conditions (rolling material heating temperature 900 ° C. as conditions for easy seizure). As a result of the evaluation in (1), many seizure flaws were generated on the entire surface of the rolled material in Comparative Example 3 in Comparative Examples 1 and 2, but the sulfurized ester and polysulfide were 50%.
Examples 1, 2, 4 and 7 in which -80% by mass and a cationic surfactant were added were good, and especially those in which 80% by mass were added did not cause seizure flaws at all. (2) Similarly, as a result of measuring the friction coefficient at the time of biting, Examples 1, 2, 4, and 7 are 0.29 in the case of SUS-444.
The above was shown, and SUS-304 also showed a high friction coefficient of 0.25 to 0.26. The rolling oil containing the ester main component of Comparative Example 3 exhibited a low friction coefficient of 0.17. If the friction coefficient at the time of biting is 0.20 or more, there is no problem such as slip at the time of biting the rolled material into the roll, and the sheet passing property of the actual machine is good.

[0034]

The seizure during hot rolling of stainless steel could not be suppressed by the conventional oil, but the hot rolling oil of the present invention has a very thin oxide scale and is very easy to seize.
Even with a material such as 444, seizure can be prevented, and since the biting property is good, the effect that it can be stably applied to all stainless steel materials can be exhibited. The productivity and operability of hot rolling of stainless steel can be improved, and the surface quality in the process after cold rolling can be greatly improved. Mineral oil, fats and oils, etc. are used as the base oil, and because it is a stable liquid type, there is no problem in work, and it can be applied to the roll by the existing water injection, and the maximum effect can be exhibited. It is economical without the need to make equipment.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining a method of an emulsification dispersion test, (a) is a drawing for emulsifying and dispersing, and (b) is a drawing for explaining observing separated oil. .

FIG. 2 is a schematic explanatory view of an adhesion tester.

FIG. 3 is a schematic explanatory view of a hot Timken tester.

FIG. 4 is a schematic explanatory view of a hot rolling tester.

FIG. 5 is an explanatory diagram showing a biting angle.

[Explanation of symbols]

1. Homo mixer 2. beaker 3. Mixing liquid (oil + water) 4. Mixing equipment 5. spray nozzle 6. Rolling oil pump 7. Rolling oil tank 8. Water pump 9. Water tank 10. Test piece (SPCC-SD) 11. Pressure gauge 12. Heating test piece (30φ x 50 mm length cylinder) 13. High frequency heating coil 14. Roll (50φ x 8mm wide ring) 15. Water injection application 16. Air drainer 17. thermocouple 18. Work roll 18a. Work roll top roll 18b. Lower roll of work roll 19. Mixing equipment 20. spray nozzle 21. Gear pump 22. Water tank 23. Water pump 24. Rolling oil tank 25. Rolling oil pump 26. Rolled material (strip)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C10M 135/22 C10M 135/22 // C10N 20:00 C10N 20:00 Z 30:06 30:06 40: 24 40:24 Z (72) Inventor, Toshiki Ebisa, 1 Kawasaki-cho, Chuo-ku, Chiba, Chiba Pref., Technical Research Institute, Kawasaki Steel Co., Ltd. (72) Taichi Kukizaki, 1 Kawasaki-cho, Chuo-ku, Chiba, Chiba Iron Co., Ltd. Chiba Steel Works (72) Inventor Masato Shigemi 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Kawasaki Steel Co., Ltd. Chiba Works (72) Inventor Hideya Furusawa 1 Kawasaki-cho, Chuo-ku, Chiba City Kawasaki Steel Co., Ltd., Chiba Works (72) Inventor Yuichi Mikawa, 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Kawasaki Steel Co., Ltd., Chiba Works (72) Inventor, Kun Inagaki, Osaka Kita-ku Umeda 1-2-2-1400 Daido Chemical Co., Ltd. (72) Inventor Jiro Ikeda 1-2-2400 Umeda, Kita-ku, Osaka-shi, Osaka (72) Inventor Masami Sumitomo 2-2-1400 Umeda, Kita-ku, Osaka-shi, Osaka Prefecture F-term within Daido Chemical Industry Co., Ltd. (reference) 4H104 BE02C BE26C BE27C BG04C BG12C DA02A DA06A EA01Z EB02 EB04 LA03 PA26 PA35

Claims (3)

[Claims] 1. A sulfurized ester having a sulfur content of 10% by mass or more and / or polysulfide is added to one or more base oils of mineral oils, fats and oils and synthetic esters in an amount of from 40 to 40% of the total composition.
A hot rolling oil composition for stainless steel, containing 90% by mass and a cationic surfactant. 2. A hot rolling oil composition for stainless steel according to claim 1, which contains 0.05 to 1.5% by mass of a cationic surfactant. 3. The coefficient of friction in the hot Timken test is 0.
The hot rolling oil composition for stainless steel according to claim 1 or 2, which is 12 or more.