JPH02252799A - Rust-preventive oil for steel sheet combinedly used in press working - Google Patents

Abstract

PURPOSE:To obtain the title oil excellent in both the rustproofness during long- term storage and the lubricating performance in press working by mixing a petroleum base oil with a very highly basic sulfonate so as to provide a final product with a specified base number. CONSTITUTION:The title oil contains a petroleum base oil (e.g. mineral oil) and a very highly basic sulfonate (e.g. very highly basic Mg sulfonate) and has a basic number of the final product of at least 15mgKOH/g, preferably above about 17mgKOH/g and below about 50mgKOH/g, and a viscosity at 40 deg.C of preferably about 7-27cSt.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to anti-corrosion treatment during storage of various steel plates, especially thin steel plates, used mainly in the automobile industry, etc., and to presses when processing steel plates. This invention relates to a rust preventive oil for both press processing and press processing, which allows processing to be performed using a single lubricating oil.

(Prior Art) In general, thin steel sheets manufactured by steel manufacturers are coated with anti-corrosion oil, then rolled into coils or stacked to be shipped to users such as the automobile industry. A processed product is created by combining various press forming techniques such as bending, tension, and drawing.

The anti-corrosion oil applied at the time of shipment generally has sufficient anti-rust properties even during long-term storage, and also has good degreasing properties, less oil bleed, and a smaller amount of oil carried out. In order to meet these additional performance requirements, a low viscosity material with a viscosity of about 25 cst or less at 40C is usually used. On the other hand, during press processing, the viscosity at 40C is usually 50 to 100 by degreasing the rust preventive oil or applying the rust preventive oil.
Pressing is performed by applying cSt medium e high viscosity press oil.

In recent years, in order to achieve rationalization by simplifying the press process, there has been a demand for the anti-corrosion oil applied at the time of delivery to users such as the automobile industry to also serve as a lubricant during the press process. If this requirement is met, it will be of great benefit to the steel and automobile industries, so it has become an important issue to use a single lubricant for both rust prevention and press processing.

In this case, increasing the viscosity of the rust preventive oil to the medium or high viscosity of conventional press working oil can reduce the degreasing properties and
This is not appropriate because it causes deterioration in economic efficiency due to an increase in the amount of oil taken out, and a decrease in handling properties of the steel plate. On the other hand, there are also problems in directly using conventional press working oil as rust preventive oil. When conventional press oils are made to have a low viscosity, the oil film becomes extremely low during press processing, resulting in frequent problems such as press cracks and scratches on the processed surfaces. Therefore, in order to enhance the lubricity, it is possible to add common extreme pressure additives, such as those containing elements such as chlorine, sulfur, phosphorus, and molybdenum. However, adding a general extreme pressure agent to this type of rust preventive oil significantly reduces its rust preventive properties. For example, moisture in the air reacts with extreme pressure agents to produce acidic substances, resulting in rust, oil stains, and discoloration of the board surface. In particular, in recent years, the proportion of surface-treated steel sheets in steel sheets has been increasing, and compared to conventional hot-rolled and cold-rolled steel sheets, these surface-treated steel sheets are less susceptible to flaking of the plating layer and powdering during press forming. For this reason, the lubricating oil used is required to have better lubricity than before, but the surface plating layer
In particular, it easily reacts with extreme pressure agents, causing oil stains on steel plates, corrosion and discoloration of plating layers, etc.

Thus, with the current combination of additives, it is impossible to satisfy both rust prevention and press workability using either commercially available rust preventive oils for steel plates or press working oils.

(Problems to be Solved by the Invention) An object of the present invention is to solve these problems and provide a rust preventive oil for steel plates that provides excellent press working lubricity without reducing rust preventive performance.

(Means to Solve the Problem) In other words, as a result of intensive studies to solve the above problem, the present inventors have found that the processability of rust preventive oil is significantly improved by adding ultra-high basic sulfonate at a certain concentration or more. The present invention was completed based on the discovery that this can be done.

That is, the present invention comprises a petroleum base oil and an ultra-high basicity sulfonate, and the base number of the final product is 15 K.
A rust-preventing oil for press working and steel sheets characterized by having a rating of OH/P or higher.

The petroleum base oil in the present invention may be any ordinary oil, such as motor oil, machine oil, turbine oil, spindle oil, light oil, white kerosene, petrolatum, etc., and one or more of these may be used. can be used.

The ultra-high salt sulfonates used in the present invention are petroleum sulfonic acids obtained by sulfonation of aromatic hydrocarbon components in petroleum base oil fractions, or synthetic sulfonic acids such as dinonylnaphthalene sulfonic acids and heavy alkylbenzene sulfonic acids. alkali metal or alkaline earth metal salts,
It contains excessive amounts of hydroxides, oxides, or carbonates of these metals. Na is used as the alkali metal, and Ca, Ba, Mg, etc. are used as the alkaline earth metals, and the base number (JIS K 2501) is approximately 100 KO.
I-I/P or higher, preferably about 300-400 KOH
/p can be used.

Ultra-highly basic sulfonates can be obtained by methods well known in the art. For example, group I metals such as Na or B
A neutral or basic sulfonate is obtained in advance by reacting a metal group oxide, hydroxide or carbonate of group (1) such as a, Ca, Mg, etc. with a sulfonic acid.

Suitable sulfonic acids are alkylbenzenes of the formula where R is an alkyl group, R can contain from 8 to 50 carbon atoms, preferably from 8 to 35 carbon atoms. Among the sulfonic acids, ali, wax benzene sulfonic acid, octadecyl sulfonic acid and CI4 to C34 mixed alkylbenzenesulfonic acid are preferred.

The ultra-highly basic sulfonate used in the present invention is an oil solution of the neutral salt, basic salt, or a mixture of both of the sulfonate obtained in this way, and Na.

It is produced by blowing carbon dioxide into a mixed slurry of Ca or Ba hydroxide, oxide, carbonate, etc.

The addition ratio of the ultra-highly basic sulfonate is such that the base value of the final product is about 1st4KOH/or more, preferably about 17K
OH/7 or more, more preferably about 201J9KOH/?
The amount added can be increased or decreased depending on the base number of the ultra-high basic sulfonate so that it is about 50 KOH/P or less, and the amount is about 3 weight percent or more, preferably about 5.5 percent by weight based on the base oil.
It is preferable that the weight ratio is not less than t% and not more than 20% by weight.

If it is too small, the press workability will be poor, and if it is too large, the rust prevention will be poor.
The effect of press workability is on its own, but it does not increase significantly.

Although ultra-highly basic sulfonates are known as detergent-dispersing agents, they have not been known to have any performance as processability improvers.

In addition to the above-mentioned compounds, the present invention may contain known oil-soluble organic rust inhibitors, antioxidants, and the like. For example, neutral, basic sulfonates (Na salt, Ba salt, Ca salt of petroleum sulfonates and synthetic sulfonates, etc.), esters (sorbitan monooleate, pentaerythritol monooleate, sorbitan triolate, esters of wax oxides, etc.) , carvone I'll (oleyl sarcosine, dimer acid, etc.), thiophosphoric acid esters, organic amine salts (coconut oleate, etc.), and can usually be used singly or in combination of two or more. The amount of the oil-soluble organic antirust oil used is usually 0.2% by weight or more, preferably 0.5 to 20% by weight based on the petroleum base oil.
You can choose within the weight range. If it is too small, it will not be able to exhibit a sufficient rust prevention effect, and if it is too large, problems will occur in terms of solubility.

The final viscosity of the steel plate rust preventive oil used for press working, which is the present invention, is:
Approximately 7 cSt or more and 27 cst or less at 40C is preferable,
More preferably 12 cSt or more and 25 cSt or less. If it is too low, the rust prevention properties and press workability will be poor, and if it is too high, the degreasing property will deteriorate and the amount of oil carried out will increase, which is undesirable.

(Effects of the Invention) By applying the steel plate rust preventive oil for press working of the present invention to a steel plate, not only rust prevention properties but also sufficient lubricity for press working can be obtained. That is, a single lubricating oil can serve both the rust prevention properties of conventional steel plate rust prevention oils and the press workability properties of press working oils, and the processing steps can be simplified.

(Example) The present invention will be explained below with reference to Examples and Comparative Examples.

Table 1 shows the compositions of Examples and Comparative Examples. Note that the numbers in the table indicate parts by weight. Comparative Example 5 is a typical commercially available press working oil that is used in large quantities for press working of thin steel sheets in the automobile industry. The results are shown in Table 2.

In addition, the rust prevention property and press workability were evaluated by implementing the following performance test.

[Press workability evaluation test]

(1) Shell four-ball wear test (ASTM D 22
66): A wear test was performed at a rotation speed of 120 rpm, a load of 20 kpf, and a test time of 30 minutes. After the test, the wear scar diameter of the three fixed poles was averaged, and the wear prevention property was evaluated according to the following criteria. was evaluated.

Average wear scar diameter: 0.5 w or more;
A cylindrical deep drawing test was conducted at m 91 and a processing speed of 3 m/WaR, and the maximum blank diameter that could be drawn for each rust preventive oil was measured, and the second limit drawing ratio was calculated using the following formula.

Next, determine the limit drawing ratio (B) of the plate without applying any rust preventive oil in the same way, and use the ratio (A/B) when oil is applied to the limit drawing ratio when no oil is applied to make a cylindrical cylinder according to the following criteria. Deep drawability was evaluated.

A/B<2.0; Using cold-rolled steel sheets and electrogalvanized steel sheets with dimensions of After standing in a constant temperature bath with a humidity of 95% or more for 30 days, the degree of rust formation on the stacked surfaces was observed. The evaluation was based on the following criteria.

Occurrence of rust; × There is slight rust or discoloration of the plating layer; △ Both rust and discoloration are K
None; ○(4) Wet rust prevention test (J
(based on IS K 2246): In addition to cold-rolled steel sheets according to the test method, electrogalvanized steel sheets were also tested in the same manner (test time 2 weeks) as test specimens.

Wet rust prevention was evaluated according to the following criteria.

Occurrence of rust; × Slight rust or discoloration of the plating layer; △ No rust or discoloration; ○ (5) Degreasing test: 100XZooXO, 8m cold rolled steel plate and electrogalvanized steel plate were immersed in each rust preventive oil Then leave it outside for a week. After that, a 1% aqueous solution of Fine Cleaner FC4326 (Nippon Parker Rising ■) was added for 10 minutes at a temperature of 60C.
Degrease and clean by spraying for seconds.

The degreasability was evaluated based on the water-wetted area (%) of the steel plate after degreasing and cleaning.

50 ratio or less; As shown in Comparative Example 1.2.3, when a neutral or basic sulfonate is used, the lubricity is insufficient and good processing performance cannot be obtained. On the other hand, it can be seen that the commercially available press working oil of Comparative Example 5 has good press workability but has problems in rust prevention and degreasing properties.

Furthermore, as shown in Comparative Example 4, phenate, which is known to have ultra-high basicity, does not give satisfactory results in any of the tests other than the degreasing properties.

Patent applicant Cosmo Research Institute Co., Ltd. Cosmo Oil Co., Ltd. Agent

Claims (1)

[Claims] (1) A steel sheet rust preventive oil for press working, which contains a petroleum base oil and an ultra-highly basic sulfonate, and has a base number of 15 mgKOH/g or more in the final product.