JPH06256789A - Water-soluble lubricant for cold pilger rolling and method for lubrication in cold pilger rolling machine - Google Patents

Abstract

PURPOSE:To obtain the subject lubricant, excellent in cooling and lubricating performance and good in degreasing properties and operating efficiency by mixing a base oil such as a mineral oil or an animal or a vegetable oil with a lubricating additive such as an extreme-pressure additive, e.g. an alkaline earth metallic sulfonate or a chlorine-based extreme-pressure additive. CONSTITUTION:This water-soluble lubricant for cold pilger rolling is obtained by blending (A) one or two or more mixed oils of a mineral oil with an animal or a vegetable oil, a fatty acid, an ester thereof, etc., as a base oil with (B) a lubricating additive containing at least a chlorine-based extreme-pressure additive in an alkaline earth metallic sulfonate, the chlorine-based, a sulfur-based and a phosphorus-based extreme-pressure additives and (C) a surfactant. This water-soluble lubricant has 8-45wt.% content of the chlorine-based extreme-pressure additive based on the total lubricant expressed in terms of chlorine and 20-80mm<2>/s kinematic viscosity at 50 deg.C and is capable of providing 6-30 p m average particle diameter of oil particles in an aqueous emulsion prepared by taking 160g resultant water-soluble lubricant and 640g water in a 1-liter breaker and stirring the resultant mixture at 50-55 deg.C temperature for 15min with a homomixer at 7500r.p.m.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-soluble lubricant for cold pilger rolling and a lubrication method in a cold pilger rolling machine. More specifically, it is excellent in degreasing property and is capable of improving processing accuracy and working environment. And a water-soluble lubricant for cold pilger rolling in which the lubricating ability is improved to an oil level without further lowering the cooling ability, further, an emulsion of the lubricant is lubricated and cooled for the material to be rolled and the rolling tool, and The present invention relates to a lubrication method in a cold pilger rolling mill that is also used for lubrication of a roll shaft and a crankshaft.

[0002]

2. Description of the Related Art Cold pilger rolling is rolling in which bearing steel, stainless steel, etc. are rolled under a large pressure to produce a steel pipe. As the lubricant for rolling, a water-insoluble lubricant (roll oil) has been conventionally used, which is a mineral oil as a base oil and a chlorine-based extreme pressure additive.

[0003]

However, when cold pilger rolling is carried out using the above lubricant, the cooling performance of the lubricant is low, and the following problems occur. (1) The life of the rolling tool is reduced. (2) The die temperature rises and the product dimensional accuracy deteriorates.
Therefore, there is a problem in workability such that it becomes necessary to maintain the dimensional accuracy by adjusting the clearance of the die. (3) The degreasing property in the subsequent process is deteriorated due to carbonization of the roll oil adhering to the surface of the product at high temperature and increase in viscosity. (4) The environment deteriorates due to the generation of oil smoke (hydrocarbon, hydrogen chloride gas, etc.).

In order to improve the cooling performance of the above-mentioned lubricant, it is possible to apply a water-soluble lubricant, but in the case of a water-soluble lubricant, the cooling performance is good but the lubricating performance is deteriorated. It had drawbacks and was difficult to put into practical use.
As described above, in the conventional cold pilger rolling machine lubrication method, as shown in FIG. 2, cooling with an emulsion and lubrication with an oil are used together. That is, as shown in the figure and FIG. 3, the rolling tool (roll die 3 and mandrel 5) and the material to be rolled (the mother tube 1 and the product tube 1 after rolling)
The lubrication and cooling of a) is performed by an emulsion.
On the other hand, the lubrication of the bearings of the crankshaft metal bearing portion 11 and the roll shaft 4 is performed by another oil or grease in another system. However, in FIG. 2, 2 is a roll stand, 6 is an emulsion receiving tank, 7 is a connecting rod, 7
a is a connecting rod bearing, 8 is a crank chamber, 9 is a counter weight, 10 is a connecting rod, 12 is a balance weight, and 13 is an oil receiving tank. Therefore, because of the mechanism of the Pilger rolling mill, the emulsion and the oil and the like are mixed, which causes the following problems. (1) The seizure of the bearing portion occurs due to deterioration of lubrication performance. (2) The life of the emulsion is reduced. (3) It is necessary to separate and seal the emulsion and the oil, and the equipment therefor becomes complicated.

The present invention overcomes the above-mentioned drawbacks and improves the lubricating performance as much as oil without lowering the cooling performance as an emulsion, and is water-soluble for cold pilger rolling with good degreasing property and workability. An object of the present invention is to provide a lubrication method in a cold pilger rolling mill that uses a lubricant and an emulsion of the lubricant both for lubrication and cooling of a material to be rolled and a roll die and for lubrication of a roll shaft and the like.

[0006]

SUMMARY OF THE INVENTION The inventors of the present invention have investigated the effects of the components and physical properties of a water-soluble lubricant (composition) on the lubrication performance, cooling of the material to be rolled and roll dies, and roll shafts. As a result of intensive research on an aqueous emulsion that can be used for lubrication, it was found that a composition comprising a base oil, a specific sulfonate, an extreme pressure additive and a surfactant exhibits excellent performance, and the present invention is completed. Was reached. That is, the water-soluble lubricant of the first aspect of the present invention comprises (a) a mineral oil, an animal or vegetable oil and fat, one or more kinds of mixed oils selected from fatty acids and fatty acid esters as a base oil, and (b) an alkaline earth metal. A sulfonate, a chlorine-based extreme pressure additive, a sulfur-based extreme pressure additive, and a lubricating additive containing at least the chlorine-based extreme pressure additive among phosphorus-based extreme pressure additives, and (c) containing a surfactant, The content of the chlorine-based extreme pressure additive is 8 to 10 in terms of chlorine content with respect to the entire lubricant.
45% by weight and a kinematic viscosity at 50 ° C. of 20 to
It is 80 mm ² / s, and the average particle size of the oil particles of the aqueous emulsion when produced under the conditions described above is 6 to 30 μm.

In the present invention, "mineral oil" includes spindle oil, machine oil, turbine oil, etc.
As beef tallow, lard, rapeseed oil, castor oil, palm oil,
Coconut oil and the like, as "fatty acid", caproic acid, enanthic acid, caprylic acid, pelargonic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, stearic acid, oleic acid, ricinoleic acid, castor oil fatty acid Polymerized fatty acids such as condensates of the above can be used.

The "alkaline earth metal sulfonate" means an alkaline earth metal salt of various sulfonic acids, such as petroleum sulfonate and synthetic sulfonate. As the alkaline earth metal used, magnesium, calcium, barium or the like can be used. This petroleum sulfonic acid salt is a mixture of petroleum sulfonic acid, that is, a sulfonic acid mixture of hydrocarbons that are by-produced during the purification of sulfuric acid from petroleum fractions, especially white oil is purified with sulfuric acid or with a solvent to see the sludge content and fuming sulfuric acid After being heated and sulfonated, unreacted oil and waste acid were removed, the product was purified, and then neutralized with a predetermined metal. In addition, synthetic sulfonates are generally distinguished from petroleum sulfonates by sulfonating alkylbenzene, alkylnaphthalene (eg, dinonylnaphthalene), etc., which were produced by petrochemicals, and then the specified metal. It is obtained by neutralizing with.

Examples of the above-mentioned "chlorine-based extreme pressure additive" include chlorinated paraffin, chlorinated ester and the like. The content of the chlorine-based extreme pressure additive is 8 to 45% by weight in terms of chlorine content based on the entire lubricant (that is, 8 to 45 parts by weight, particularly preferably 10 to 40 parts by weight based on 100 parts of the lubricant). %)
Is. If the content is less than 8% by weight, the lubricity is insufficient, and if it exceeds 45% by weight, the performance does not change and the viscosity of the lubricant becomes too high, which causes problems in emulsification and workability.

Examples of the "sulfur-based extreme pressure additive" include sulfurized fats and oils, sulfurized fatty acid esters, olefin polysulfides, dialkyl polysulfides and the like. This addition amount is 0.5 in terms of sulfur content with respect to the entire lubricant.
-5% by weight is preferred. If this content is less than 0.5% by weight, seizure resistance becomes insufficient, and if it exceeds 5% by weight, there is no change in its performance. Examples of the above-mentioned "phosphorus-based extreme pressure additive" include phosphoric acid ester, phosphorous acid ester and the like. The addition amount is preferably 0.15 to 0.5% by weight in terms of phosphorus content with respect to the entire lubricant.

As the "surfactant", one or more of nonionic surfactants, anionic surfactants and cationic surfactants can be used. Of these, nonionic surfactants are preferable. Examples of the nonionic surfactant include polyhydric alcohol fatty acid ester (sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyglycerin fatty acid ester, propylene glycol fatty acid ester, polyoxyethylene glycol fatty acid ester, polyoxyethylene glycerin fatty acid ester, etc. ), Polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, and fatty acid alkylolamide. Examples of the anionic surfactant include known ones such as alkylbenzene sulfonic acid alkali metal salt and petroleum sulfonic acid alkali metal salt. Further, known cationic surfactants can also be used.

The “kinematic viscosity at 50 ° C.” of the lubricant of the present invention is in the range of 20-80 mm ² / s. If this kinematic viscosity is less than 20 mm ² / s, the amount of introduced oil will be insufficient and the lubricity and degreasing property will decrease, and if it exceeds 80 mm ² / s,
This is because the emulsifiability over time deteriorates and the machine area is soiled.
Furthermore, the "oil particle size" in the emulsion of the lubricant of the present invention
Has an average particle size of 6 to 30 μm (preferably 7 to 2).
0 μm). This is because if the average particle size is less than 6 μm, the lubricity decreases, and if it exceeds 30 μm, the emulsifying property over time deteriorates, the amount of stains around the machine increases, and the cleaning liquid deteriorates quickly.

A lubrication method in a cold pilger rolling mill according to the second aspect of the present invention is to lubricate at least a material to be rolled and a roll die with an aqueous emulsion formed by adding water to the water-soluble lubricant according to the first aspect. It is characterized by being used for both cooling and lubrication of the roll shaft and crankshaft. In addition, the target other than the above that can be used for this purpose is
Lubrication of the connecting rod bearing or the like may be used. Incidentally, since grease is not normally applied to this connecting rod bearing, grease is used.

[0014]

The present invention will be described in detail below with reference to examples. (1) Preparation of Lubricant Table 1 shows the compositions of the lubricants (also referred to as sample oils) according to Examples 1 to 12 included in the scope of the present invention, and Table 2 shows Comparative Example 1 not included in the scope of the present invention. The compositions of the lubricants according to 4 are shown below.
The lubricating oil of Comparative Example 4 in Table 2 is a commonly used roll oil (water-insoluble lubricating oil) and does not contain a surfactant. The unit of numerical values showing the composition in these tables is% by weight based on 100% by weight of the entire lubricant (composition). In Table 2, those not included in the scope of the present invention are marked with *.

In these tables, "mineral oil" means a mixture of machine oil and spindle oil, "polymerized fatty acid" means castor oil fatty acid condensate, "chlorinated paraffin" has 12 carbon atoms and chlorine content. : 50% by weight, "sulfurized fatty acid ester" has a sulfur content of 10% by weight,
"Dilauryl hydrogen phosphite" has a phosphorus content of 7% by weight, and "calcium sulfonate"
Has a calcium content of 12% by weight, "nonionic surfactant A" is sorbitan monooleate, "nonionic surfactant B" is nonylphenol with 4 moles of ethylene oxide added, and "nonion The "surfactant C" is a nonylphenol with 6 moles of ethylene oxide added, and the "nonionic surfactant D" is a nonylphenol with 8.5 moles of ethylene oxide added to the "anionic surfactant A". Sodium dodecylbenzene sulfonate was used, and "antioxidant" was 2,6-di-tert-p-cresol.

[0016]

[Table 1]

[0017]

[Table 2]

In Table 3, the kinematic viscosities (50 ° C.) of the lubricants (sample oils) according to Examples 1 to 12 and Comparative Examples 1 to 4 and the water-based emulsions were prepared as follows. The average particle size is shown. That is, this emulsion was prepared by placing 160 g of sample oil and 640 g of water in a 1 liter beaker and heating it at a temperature of 50 to 55 ° C. for 15 minutes using a homochismer to obtain 7,5.
An emulsion was prepared by stirring under 00 rpm. Then, the average particle size of the oil particles in this emulsion was measured with a Coulter counter. In this table, those not included in the scope of the present invention are marked with *.

[0019]

[Table 3]

(2) Performance Evaluation The following performance test was conducted to clarify the performance of the water-soluble lubricant of the present invention. Lubricity With a Timken friction tester, load bearing performance (OK load: 1b
f) was measured and the results are shown in Table 4. The test conditions are as follows. Test cup material: SUJ-2 Test block material: SUJ-2 Rotation speed: 800 rpm Sample temperature: 50 ° C. Sample concentration: 20 wt% (20 parts by weight sample oil / 80 parts by weight water) OK load: Maximum without scoring Load (1b
f)

[0021]

[Table 4]

Degreasing Property A sample oil was applied to a test piece (SUJ-2, 60 × 80 × 0.8 mm), left for 5 hours, then immersed in methylene chloride and washed to examine the degreasing property. The results are shown in Table 5. The test conditions are as follows. Standing temperature; Examples 1 to 12: 50 ° C, Comparative Examples 1 to 3: 8
0 ° C. Comparative Example 4: 150 ° C. Methylene chloride solution temperature; 25 ° C. Immersion time; 1 minute Drying after washing; 60 ° C. × 30 minutes

[0023]

[Table 5]

Coolability Test piece at 350 ° C. (SUS304, 40 × 150 mm
φ) an emulsion having a sample concentration of 20% by weight of the sample oil of Example 4 (20 parts by weight of sample oil / 80 parts by weight of water, temperature: 5)
(0 ° C.) and the sample oil according to Comparative Example 4 (temperature: 50 ° C.) were supplied, the time (seconds) for cooling the test piece temperature to 100 ° C. was measured. The result is shown in FIG.

Coolability, product dimensional accuracy, and generation of oil smoke Tests were carried out using an actual machine test, and the results are shown in Table 6.
The conditions (apparatus) for the actual machine test are as follows. Steel type; SUJ-2 actual equipment; 21/2 "cold pilger mill Specifications of material to be rolled; Outer diameter (OD): 20-60 mmφ Wall thickness (WT): 1.5-10 mm Length: 4,500-16 1,000 mm Generator capacity; DC145 kW Rolling conditions; Rotation speed 150 rpm (stroke / min) x 6
~ 8 mm / stroke emulsion and lubricating oil used; same as above (20% by weight of lubricating oil of Example 1
Emulsion and the lubricating oil itself according to Comparative Example 4 = roll oil)

Lubrication cooling method: The emulsion of Example 1 is shown in the system diagram of FIG. That is, 600 liters and 1200 liters of this emulsion are stored in a crank tank (volume 800 liters) 14 below the crank chamber 8 and a roll stand tank (volume 1400 liters) 16 below the roll stand 2, respectively. Then, each of the tanks stores the return emulsion in the roll stand or the return emulsion in the crank chamber, and the emulsion is circulated and used by the pipes 15, 17 and 18. Further, the emulsion supplied from the roll stand tank 16 is divided into four after leaving the pump 19, and the inlet rolling lubrication 1
7a, roll shaft bearing lubrication 17b, outlet rolling lubrication 17c and inner surface lubrication 17d. Further, crankshaft metal lubrication is performed through the crankshaft internal pipe 18a. However, the method for lubricating and cooling the roll oil of Comparative Example 4 is performed as described above, as shown in FIG. Table 6 shows the emulsion composition, the outer shape / thickness of the mother tube or product tube of the material to be rolled, the Pilger roll die temperature, and the temperature of the material to be rolled on the mill exit side. In addition, the amount of movement of product outer dimensions and the presence or absence of oil smoke are also shown in the table.

[0027]

[Table 6]

(3) Effects of Examples According to the results of Tables 4 and 5, Comparative Examples 1 to 3 all had poor lubricity, and Comparative Example 2 also had poor degreasing properties.
In Comparative Example 4, the undiluted liquid (roll oil) was used, and thus the lubricity was equal to or higher than that of each Example, but the degreasing property was remarkably poor. On the other hand, in each of Examples 1 to 12, the lubricity is equal to or slightly worse than that of the roll oil (lubricating oil of Comparative Example 4) in spite of the emulsion, and is extremely excellent as a water-based emulsion which has never been obtained before. (Table 4). The degreasing rate is 9 in Examples 1 to 12.
0 to 95%, which is extremely superior to that of the comparative example (30 to 83%) (Table 5).

Furthermore, according to the result of the actual machine test (Table 6),
The comparison between the emulsion of Example 1 and the roll oil of Comparative Example 4 is as follows. The surface temperature of the Pilger roll die was 28% (Test No. 1) and 36% (Test No. 1).
2) and 35% (Test No. 3) decreased, and the life was about 2
It improved by 5%. Further, the surface temperature of the material to be rolled on the mill exit side is the same as that of the test No. All of 1 to 3 decreased by 49%, and although steam was generated, smoke was not generated due to oil burning and the environment was significantly improved. In addition, oil smoke was generated in the comparative example (Test No. 3). Further, the product outer diameter dimensional accuracy (dimension change amount) of the roll stand stop portion is 40% (test no.
1), 43% (Test No. 2) and 50% (Test No. 2).
3) also improved. In addition, even when continuous operation was performed for 60 days after the start of operation, seizure and abnormal wear did not occur in this example. Further, similarly, even after the operation for 60 days, pitching of the roll shaft bearing did not occur, and the life was improved by 50% or more as compared with the comparative example. In the comparative example, pitching occurred after 60 days of use.

The present invention is not limited to the specific examples described above, and various modifications may be made within the scope of the present invention according to the purpose and application. That is,
Although the present invention comprises the above components, an oiliness improver, an antioxidant, an anticorrosive and the like can be appropriately added as other optional components.

[0031]

INDUSTRIAL APPLICABILITY The water-soluble lubricant for cold pilger rolling of the present invention is excellent in cooling property, lubricity property and degreasing property (that is,
It is possible to improve the lubricating performance as much as oil without lowering the cooling performance as an emulsion. )
Therefore, it is possible to improve the working environment by reducing the generation of hydrogen chloride gas, improve the yield by improving the degreasing property, and improve the productivity by improving the dimensional accuracy of steel pipe products. Further, according to the lubrication method in the cold pilger rolling mill of the present invention, it is possible to perform rolling excellent in cooling property, lubricity property and degreasing property, and to lubricate the material to be rolled and the rolling tool with an aqueous emulsion of the above lubricant. It is also very convenient because it can be used for both cooling and lubrication of the roll shaft and crankshaft.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the relationship between the temperature of a test piece and the time for cooling to 100 ° C. in Example 4 and Comparative Example 4.

FIG. 2 is a system diagram showing a lubricating and cooling method when a conventional roll oil is used in a cold pilger rolling mill.

FIG. 3 is an explanatory diagram showing a state in which a material to be rolled is rolled using a roll die.

FIG. 4 is a system diagram showing a lubrication cooling method in the case of using an emulsion prepared by using the lubricant of Example 1 in a cold pilger rolling mill.

[Explanation of symbols]

1; Mother tube, 1a; Rolled product tube, 2; Roll stand, 3; Roll die, 4; Roll shaft, 5; Mandrel, 6; Emulsion receiving tank, 7; Connecting rod, 7
a; connecting rod bearing, 8; crank chamber, 9; counterweight, 10; connecting rod, 11; crankshaft metal bearing portion, 12; balance weight, 13;
Oil receiving tank, 14; Crank tank, 16; Roll stand tank, 17a; Inlet rolling lubrication, 17b; Roll shaft bearing lubrication, 17c; Outlet rolling lubrication, 18a; Crankshaft piping.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location C10M 101: 04 109: 02 131: 14 135: 10 129: 16 129: 40 135: 06 137: 02 ) C10N 10:04 30:00 A 8217-4H 30:02 40:24 Z 8217-4H 70:00 (72) Inventor regulation No. 3007 Nakajima character 1 letter Nakajima, Himeji City, Hyogo Prefecture Sanyo Special Steel Co., Ltd.

Claims (2)

[Claims] 1. A base oil comprising (a) one or a mixture of two or more selected from mineral oils, animal and vegetable oils and fats, fatty acids and fatty acid esters, and (b) an alkaline earth metal sulfonate and a chlorine-based extreme pressure additive. A lubricant additive containing at least the chlorine-based extreme pressure additive of a sulfur-based extreme pressure additive and a phosphorus-based extreme pressure additive, and (c) a surfactant. The content is 8 to 45% by weight in terms of chlorine content with respect to the entire lubricant, and the kinematic viscosity at 50 ° C. is 20 to 80 mm ² / s. The average particle size of oil particles is 6 to
A water-soluble lubricant for cold pilger rolling, which has a thickness of 30 μm. Emulsion preparation conditions: 160 g of the above water-soluble lubricant and 640 g of water are placed in a 1-liter beaker and stirred at a temperature of 50 to 55 ° C. for 15 minutes at 7,500 rpm using a homochimiser. 2. A lubrication method in a cold pilger rolling mill, wherein an aqueous emulsion formed by adding water to a water-soluble lubricant for cold pilger rolling according to claim 1 is used to lubricate at least a material to be rolled and a roll die. A lubricating method for a cold pilger rolling machine, which is used for both cooling and lubrication of a roll shaft and a crankshaft.