JPH061992A - Cold rolling method - Google Patents

Abstract

(57) [Summary] [Purpose] To perform temper rolling at a high pressure reduction rate that does not cause a problem in rust prevention by using emulsion type temper rolling liquid. [Composition] Rolling oil 0.5-2.0% by volume and carbon number 8-
Alkanolamine salts of 16 dibasic acids 0.05-0.5
Rolling the annealed cold rolled steel sheet to a rolling reduction of 3-10% using an emulsion containing volume% and rolling oil 2.0-5.0 volume% and alkanolamine salt of dibasic acid 0-0. Rolling the annealed rolled steel sheet to a rolling reduction of 10 to 50% using an emulsion containing 0.5% by volume.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a cold rolling method.

[0002]

2. Description of the Related Art Conventionally, temper rolling at a high pressure reduction ratio (reduction ratio of 3 to 10%) called HRT is performed using a water-soluble temper rolling liquid, and an emulsion type temper rolling liquid is not used. Not not. The reason is that if an emulsion-type tempered rolling liquid is used, the lubricity becomes too high, and as a result, the rolling load becomes light and the shape control becomes difficult. The method of lowering the effective component concentration of the emulsion-type tempered rolling liquid is not practical because it causes rusting of the obtained rolled steel sheet. A method of applying a rust preventive agent on the surface of the steel sheet after rolling in order to prevent rusting is also conceivable, but it is troublesome twice, which causes a problem in practical use. Although a method of adding a rust preventive agent to the emulsion type temper rolling liquid is also considered, a method of achieving excellent rust preventive property without impairing rolling property and emulsion stability has not been proposed yet. On the other hand, the water-soluble tempered rolling liquid that has been generally used for the HRT is difficult to separate the water-soluble organic component from the water, and therefore the wastewater treatment becomes extremely difficult, which requires a large-scale wastewater treatment facility and a large amount of money. Processing costs are required.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides an oil agent composition which can be used for both HRT and 2CR having conflicting required characteristics with a single oil agent, and in particular, an emulsion type temper rolling liquid is used to prevent rusting. It is an object of the present invention to provide a technique for obtaining a cold rolled steel sheet with a suppressed high rolling reduction.

[0004]

SUMMARY OF THE INVENTION The present invention is a cold rolling oil containing a rolling oil and an alkanolamine salt of a dibasic acid having 8 to 16 carbon atoms. 0.5-2.0% by volume and 8 carbon atoms
~ 16 alkanolamine salts of dibasic acids 0.05 to 0.
It relates to a cold rolling method characterized by rolling an annealed cold rolled steel sheet to a rolling reduction of 3 to 10% using an aqueous emulsion containing 5% by volume as a temper rolling liquid. Furthermore, the present invention relates to a circulating cold rolling oil coolant system, wherein an aqueous emulsion containing an emulsion concentration of rolling oil of 2.0 to 5.0% by volume and an alkanolamine of dibasic acid of 0 to 0.5% by volume. Is used as a temper rolling liquid to cool an annealed cold rolled steel sheet to a rolling reduction of 10 to 50%.

The rolling oil used in the present invention may be any one conventionally used as an emulsion type rolling oil, but is typically an ester with a fatty acid polyol as a base oil, for example, ethylene glycol. , Propylene glycol, glycerin, polyglycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, sorbitan and the like and fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, erucic acid, ricinoleic acid, Examples thereof include esters with hydroxystearic acid. It is preferable that these esters are contained in an amount of 40 to 98% by weight or more based on the total weight of rolling oil. The ester may be a mixture of two or more kinds, or may be a mixture of monoester and polyester.

As the base oil, mineral oil, synthetic hydrocarbons such as polyolefin, etc. may be used, but those having a pour point of 0 ° C. or lower as the whole base oil are preferable. If the pour point of the base oil is higher than 0 ° C., the mill housing rolling oil adheres, and if these fall on the plate surface, it becomes a surface defect of the steel plate. The emulsion concentration of the rolling oil used in the present invention is 0.5 to 2.0% by volume. If the concentration exceeds 2.0%, the rolling load is too light and shape control is difficult.
On the other hand, if it is less than 0.5%, rollability and rust prevention after rolling become problems.

In the present invention, a rolling oil emulsion,
An alkanolamine salt of a dibasic acid having 8 to 16 carbon atoms is added in an amount of 0.05 to 0.5% by volume. As the dibasic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid,
Examples include dodecanedioic acid and tridecanedioic acid. An alkanolamine salt of a dibasic acid having 8 to 16 carbon atoms is used. If the carbon number is less than 8, the rust preventive power is not sufficient,
When the carbon number is more than 16, degreasing property after rolling becomes a problem. The alkanolamine may be any of monoethanolamine, diethanolamine and triethanolamine, and is used in an amount of 1.5 to 2.2 equivalents based on the dibasic acid used. If it is less than 1.5 equivalents, the effect of atomizing the emulsion is small, and if it is more than 2.2 equivalents, the rust preventive effect per addition amount decreases. In the present invention, the tempered rolling liquid containing the dibasic acid alkanolamine added to the rolling oil emulsion in an amount of 0.05 to 0.5% by volume does not cause a significant reduction in rolling load, and has a rolling reduction ratio of 3 to 10 by HRT. %
And the obtained rolled steel sheet is provided with excellent rust prevention.

When the emulsion concentration of the rolling oil used in the present invention is 2.0 to 5.0% by volume and the concentration of the alkanolamine salt of dibasic acid is 0 to 0.5% by volume, the rolling reduction is 10%. -50% 2CR (a manufacturing method of a tin plate that is annealed and then rolled again) is possible, and a single oil agent can provide an oil agent that can be used for both HRT and 2CR having conflicting required properties. Hereinafter, the present invention will be described with reference to examples.

A rolling oil having the following formulation was prepared. % By Weight Trimethylolpropane Mixed Fatty Acid Ester 89.9 Dimer Acid 1.0 Phosphorus Extreme Pressure Additive 1.0 Ether Nonionic Surfactant 1.5 Ester Nonionic Surfactant 1.5 Antioxidant 0.9. 1 Antifungal Agent 0.1 In addition, an additive having the following formulation (alkanolamine salt of dibasic acid) was added. Weight% Dodecanedioic acid 30.0 Diethanolamine 54.0 Water 16.0

2CR rolling An aqueous emulsion containing 3.0% by volume of the above rolling oil was prepared,
While supplying this to a roll, it was subjected to 2CR rolling under the following conditions. Rolling conditions Rolling speed: 1300 mpm Work roll roughness: 0.4 μmRa to 0.6 μmRa Rolling plate: Annealed thin steel plate 0.25 mm × 850 mm Rolling oil emulsion temperature: 60 ° C. Rolling reduction was 30%, 25% and 20% The rolling property and the rust preventive property were evaluated and are shown in Table 1. From the above test results, it can be seen that this rolling oil can be suitably used for 2CR rolling.

HRT rolling An aqueous emulsion containing 1.0% by volume of the above rolling oil was prepared,
While supplying this to a roll, it was subjected to HRT rolling under the same conditions as above. However, the reduction rates are 8%, 6% and 4%,
At that time, the rolling property and the rust prevention property were evaluated. The results are shown in Table 1.
Shown in. On the other hand, an additive in an amount corresponding to 30% by weight of the rolling oil was added to the rolling oil emulsion, and HRT rolling was performed in the same manner as above. The results are shown in Table 1.

[0012]

[Table 1]

[0013]

The oil agent of the present invention can be used for both HRT and 2CR. Further, by using the method of the invention, it is possible to carry out temper rolling (HRT) at a high pressure reduction rate using an emulsion type temper rolling liquid. The emulsion concentration needs to be lower than that of the HRT using the water-soluble temper rolling liquid, but the rust that normally occurs at that time can be suppressed.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical display location C10M 129: 28 133: 08) C10N 40:24 Z 8217-4H (72) Inventor Yuushi Kodama Tobata, Kitakyushu, Fukuoka Prefecture 1-1 Hibahata-ku, Shin-Nippon Steel Co., Ltd., Yawata Works (72) Inventor Tetsuya Tsukamoto 2-3-1, Shibukawa-cho, Yao-shi, Osaka Japan Quaker Chemical Co., Ltd. (72) Inventor Koichi Morikawa 2-3 1-3 Shibukawa-cho, Yao-shi, Osaka Japan Quaker Chemical Co., Ltd.

Claims (2)

[Claims] 1. A circulating cold rolling oil coolant system comprising 0.5 to 2.0% by volume of rolling oil and 8 to 16 carbon atoms.
Of an alkanolamine salt of a dibasic acid of 0.05 to 0.5% by volume is used as a tempering rolling liquid, and the annealed cold rolled steel sheet is further rolled to a rolling reduction of 3 to 10%. Cold rolling method. 2. A circulating cold rolling oil coolant system, wherein the emulsion concentration of rolling oil is 2.0 to 5.0% by volume and the dibasic acid alkanolamine is 0 to 0.5.
Aqueous emulsion containing volume% as temper rolling liquid,
A cold rolling method comprising rolling an annealed cold rolled steel sheet to a rolling reduction of 10 to 50%.