JP2623058B2 - Water-soluble lubricant for cold pilger rolling and lubrication method in cold pilger rolling mill - Google Patents

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 lubricating method for a cold pilger rolling mill, and more particularly to improving the degreasing property and improving the processing accuracy and working environment. Can be, water-soluble lubricant for cold pilger rolling improved lubricating ability to the same level as oil without further lowering the cooling ability, further lubricating and cooling the emulsion of the lubricant to the material to be rolled and the rolling tool, and The present invention relates to a lubrication method for a cold pilger rolling mill which is also used for lubrication of a roll shaft and a crank shaft.

[0002]

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

[0003]

However, when cold pilger rolling is performed using the above-mentioned lubricant, the following problems arise because the cooling performance of the lubricant is low. (1) The life of the rolling tool is reduced. (2) The die temperature rises and the product dimensional accuracy deteriorates.
For this reason, there is also a problem of workability such as the necessity of maintaining the dimensional accuracy by performing a clearance adjustment operation of the die. (3) The degreasing property in the subsequent process is reduced due to the carbonization and viscosity increase of the roll oil attached to the surface of the product at a high temperature. (4) The environment deteriorates due to the generation of oil smoke (hydrocarbon and hydrogen chloride gas, etc.).

In order to improve the cooling performance of the above-mentioned lubricant, it is conceivable to use a water-soluble lubricant. In the case of a water-soluble lubricant, however, the lubrication performance is deteriorated although the cooling performance is good. It has drawbacks and is difficult to put into practical use.
As described above, in the lubrication method of the conventional cold Pilger rolling mill, as shown in FIG. 2, cooling by emulsion and lubrication by oil are used together. That is, as shown in FIG. 3 and FIG. 3, the rolling tool (the roll die 3 and the mandrel 5) and the material to be rolled (the mother pipe 1 and the product pipe 1 after the rolling).
The lubrication and cooling of a) are performed by an emulsion.
On the other hand, lubrication of the crankshaft metal bearing portion 11 and the bearing of 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 indicates a connecting rod bearing, 8 indicates a crank chamber, 9 indicates a counterweight, 10 indicates a connecting rod, 12 indicates a balance weight, and 13 indicates an oil receiving tank. Therefore, the emulsion and the oil are mixed on the mechanism of the Pilger rolling mill, so that the following problem occurs. (1) 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, which complicates equipment.

The present invention overcomes the above-mentioned drawbacks and improves the lubricating performance of an emulsion without lowering the cooling performance of an emulsion and at the same level as oil. An object of the present invention is to provide a lubricating method for a cold pilger rolling mill in which a lubricant and an emulsion of the lubricant are used for lubrication and cooling of a material to be rolled and a roll die, and also for lubrication of a roll shaft and the like.

[0006]

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

[0007] In the present invention, the "mineral oil" includes spindle oil, machine oil, turbine oil and the like.
As beef tallow, lard, rapeseed oil, castor oil, palm oil,
Coconut oil and the like as "fatty acids" include 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 above "alkaline earth metal sulfonate" refers to alkaline earth metal salts of various sulfonic acids, such as petroleum sulfonic acid salts and synthetic sulfonic acid salts. As the alkaline earth metal to be used, magnesium, calcium, barium and the like can be used. This petroleum sulfonic acid salt is a petroleum sulfonic acid, that is, a sulfonic acid mixture of hydrocarbons by-produced in the refining of sulfuric acid in petroleum fractions, in particular, sulfuric acid or solvent refining of white oil to look into sludge, and to generate fuming And purified by removing unreacted oil and waste acid, and then neutralized with a predetermined metal. In addition, the synthetic sulfonate is generally distinguished from petroleum sulfonate, and sulfonates alkylbenzene or alkylnaphthalene (for example, dinonylnaphthalene) or the like produced from petrochemicals, and thereafter, a predetermined metal It is obtained by neutralizing with.

The above "chlorine extreme pressure additive" includes chlorinated paraffin, chlorinated ester and the like. The content of the chlorine-based extreme pressure additive is 8 to 45% by weight (that is, 8 to 45 parts by weight, particularly preferably 10 to 40% by weight, based on 100 parts of the lubricant) in terms of chlorine based on the entire lubricant. %)
It 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, causing problems in emulsification and workability.

The "sulfur-based extreme pressure additive" includes sulfurized oils and fats, sulfurized fatty acid esters, olefin polysulfides, dialkyl polysulfides and the like. This addition amount is 0.5% in terms of sulfur content relative to the entire lubricant.
~ 5% by weight is preferred. If the content is less than 0.5% by weight, the seizure resistance becomes insufficient, and if it exceeds 5% by weight, there is no change in its performance. Examples of the “phosphorous extreme pressure additive” include phosphoric acid esters and phosphite esters. The addition amount is preferably from 0.15 to 0.5% by weight in terms of phosphorus based on 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 preferred. Examples of the nonionic surfactant include polyhydric alcohol fatty acid esters (such as sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyglycerin fatty acid esters, propylene glycol fatty acid esters, polyoxyethylene glycol fatty acid esters, and polyoxyethylene glycerin fatty acid esters). ), Polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, fatty acid alkylolamide, and the like. Examples of the anionic surfactant include known ones such as alkali metal salts of alkyl benzene sulfonic acid and alkali metal salts of petroleum sulfonic acid. Further, known cationic surfactants can be used.

The "kinematic viscosity at 50 ° C." of the lubricant of the present invention is in the range of 20 to 80 mm ² / s. When the kinematic viscosity is less than 20 mm ² / s, the lubricating and degreasing properties are reduced due to an insufficient amount of the introduced oil, and when the kinematic viscosity exceeds 80 mm ² / s,
This is because the emulsifiability over time deteriorates and soils around the machine.
Furthermore, the "oil particle size" in the emulsion of the lubricant of the present invention
Has an average particle diameter of 6 to 30 μm (preferably 7 to 2 μm).
0 μm). If the average particle size is less than 6 μm, the lubricity decreases, and if the average particle size exceeds 30 μm, the emulsifying property over time deteriorates, stains around the machine increase, and the deterioration of the cleaning liquid also accelerates.

The lubricating method in the cold pilger rolling mill according to the second invention is characterized in that the aqueous emulsion formed by adding water to the water-soluble lubricant according to the first invention is used to lubricate at least the material to be rolled and the roll die. It is also used for cooling and lubrication of the roll shaft and crank shaft. In addition, the objects other than the above that can be used
Lubrication such as a connecting rod bearing may be used. Normally, grease is used because no coolant is applied to the connecting rod bearing.

[0014]

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

In these tables, "mineral oil" refers to a mixture of machine oil and spindle oil, "polymerized fatty acid" refers to a castor oil fatty acid condensate, and "chlorinated paraffin" has 12 carbon atoms and a chlorine content. : 50% by weight, and “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"
Is a nonionic surfactant having a calcium content of 12% by weight, "nonionic surfactant A" is sorbitan monooleate, "nonionic surfactant B" is nonylphenol obtained by adding 4 moles of ethylene oxide to "nonionic surfactant B", "Surfactant C" is a nonyl phenol obtained by adding 6 moles of ethylene oxide, "Nonionic surfactant D" is a nonyl phenol obtained by adding 8.5 moles of ethylene oxide, and "anionic surfactant A" Was sodium dodecylbenzenesulfonate, and 2,6-di-tert-p-cresol was used as the "antioxidant".

[0016]

[Table 1]

[0017]

[Table 2]

Table 3 shows the kinematic viscosities (50 ° C.) of the lubricants (sample oils) according to Examples 1 to 12 and Comparative Examples 1 to 4 and water-based emulsions prepared as follows. Shows the average particle size. That is, this emulsion takes 160 g of sample oil and 640 g of water in a 1-liter beaker, and is heated at a temperature of 50 to 55 ° C. for 15 minutes using a homokimizer for 7.5 minutes.
The mixture was stirred at 00 rpm to form an emulsion. Then, the average particle diameter of the oil particles in the 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 tests were performed to clarify the performance of the water-soluble lubricant of the present invention. Lubricity Withstand load performance (OK load: 1b) by Timken friction tester
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 Number of revolutions: 800 rpm Sample temperature: 50 ° C Sample concentration: 20% by weight (sample oil 20 parts by weight / water 80 parts by weight) OK load: maximum without scoring Load (1b
f)

[0021]

[Table 4]

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

[0023]

[Table 5]

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

The cooling performance, the dimensional accuracy of the product, and the generation of oily smoke were tested using actual equipment tests, and the results are shown in Table 6.
The conditions (apparatus) of the actual machine test are as follows. Steel type; SUJ-2 actual machine; 21/2 "cold pilger mill Specifications of material to be rolled; outer diameter (OD): 20 to 60 mmφ wall thickness (WT): 1.5 to 10 mm length: 4,500 to 16 , 2,000 mm Generator capacity; DC 145 KW Rolling conditions: Rotation speed 150 rpm (stroke / min) x 6
Emulsion and lubricating oil used at 〜8 mm / stroke; same as above (20% by weight of lubricating oil of Example 1)
Emulsion and the lubricating oil according to Comparative Example 4 itself = 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 (capacity 800 liters) 14 below the crank chamber 8 and a roll stand tank (capacity 1400 liters) 16 below the roll stand 2, respectively. Each tank stores a return emulsion in a roll stand or a return emulsion in a crankcase, and the emulsion is circulated and used by each of the pipes 15, 17, and 18. Further, the emulsion supplied from the roll stand tank 16 is divided into four parts after leaving the pump 19, and is subjected to 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 pipe 18a in the crankshaft. However, the method of lubricating and cooling the roll oil of Comparative Example 4 is performed as described above as shown in FIG. Table 6 shows the composition of the emulsion, the outer shape / wall thickness of the mother pipe or product pipe of the material to be rolled, the temperature of the Pilger roll die, and the temperature of the material to be rolled on the mill exit side. The table also shows the movement of the external dimensions of the product and the occurrence of oil smoke.

[0027]

[Table 6]

(3) Effects of the Examples According to the results of Tables 4 and 5, in Comparative Examples 1 to 3, the lubricating properties were all poor, and in Comparative Example 2, the degreasing was also poor.
In Comparative Example 4, although the lubricating property was equal to or higher than that of each of the examples because the stock solution (roll oil) was used, the degreasing property was extremely poor. On the other hand, in each of Examples 1 to 12, the lubricity was equal to or slightly worse than that of the roll oil (the lubricating oil of Comparative Example 4) despite the emulsion, and the water-based emulsion was extremely excellent as never before. (Table 4). The degreasing rate was 9 in Examples 1 to 12.
0 to 95%, which is much better than the comparative example (30 to 83%) (Table 5).

Further, according to the results of the actual machine test (Table 6),
The following is a comparison between the emulsion of Example 1 and the roll oil of Comparative Example 4. The pilger roll die surface temperature was 28% (Test No. 1) and 36% (Test No. 1).
2) and 35% (test No. 3) are reduced, and the life is about 2%.
Up 5%. In addition, the surface temperature of the material to be rolled on the mill exit side is the same as that of Test No. All of the samples 1 to 3 were reduced by 49%, and although there was generation of water vapor, there was no generation of smoke due to burning oil, and the environment was greatly improved. In the comparative example (test No. 3), oily smoke was generated. Further, the product outer diameter dimensional accuracy (dimensional change amount) of the roll stand stop portion is 40% (test No.
1), 43% (Test No. 2) and 50% (Test No. 2)
3) has also improved. In addition, in the case of the continuous operation for 60 days after the start of the operation, in this example, there was no seizure or abnormal wear. 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 compared to the comparative example. In the comparative example, pitching occurred after 60 days of use.

It should be noted that the present invention is not limited to the specific embodiments described above, but can be variously modified within the scope of the present invention in accordance with the purpose and application. That is,
The present invention is composed of the above components, but an oiliness improver, an antioxidant, an anticorrosive, and the like can be appropriately added as other optional components as needed.

[0031]

The water-soluble lubricant for cold pilger rolling of the present invention has excellent cooling, lubricating and degreasing properties (ie,
The lubrication performance can be improved as low as oil without lowering the cooling performance of the emulsion. )
Therefore, the working environment can be improved by reducing the generation of hydrogen chloride gas, the yield can be improved by improving the degreasing property, and the productivity can be improved by improving the dimensional accuracy of the steel pipe product. Further, according to the lubricating method in the cold pilger rolling mill of the present invention, it is possible to perform rolling excellent in cooling, lubricating and degreasing properties, and to lubricate a material to be rolled and a rolling tool with an aqueous emulsion of the lubricant. This is very convenient because it can also be used for cooling and cooling, lubrication of the roll shaft and crank shaft, and the like.

[Brief description of the drawings]

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

FIG. 2 is a system diagram showing a lubrication 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 when an emulsion made using the lubricant of Example 1 is used in a cold pilger rolling mill.

[Explanation of symbols]

Reference Signs List 1; mother pipe, 1a; product pipe after rolling, 2; roll stand, 3; roll die, 4; roll shaft, 5; mandrel, 6; emulsion receiving tank, 7;
a; connecting rod bearing, 8; crank chamber, 9; counterweight, 10; connecting rod, 11; crankshaft metal bearing part, 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;

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency 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 30:02 40:24 70:00 (72) Inventor Honda Chisada, 3007 Nakajima character, Shizuma-ku, Himeji-shi, Hyogo Prefecture Chiyama Sanyo Special Steel Co., Ltd. (56) References JP 62-149795 (JP, A) JP-A-2-175798 (JP, A)

Claims (2)

(57) [Claims] 1. A base oil comprising (a) one or more mixed oils selected from mineral oils, animal and vegetable fats and oils, fatty acids and fatty acid esters, and (b) alkaline earth metal sulfonates, chlorine-based extreme pressure additives. 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 based on the whole lubricant, and the kinematic viscosity at 50 ° C. is 20 to 80 mm ² / s, and the water-based emulsion produced under the following conditions: The average particle size of the 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-mentioned water-soluble lubricant and 640 g of water are placed in a 1-liter beaker, and the mixture is stirred at a temperature of 50 to 55 ° C. for 15 minutes at 7,500 rpm using a homochimizer. 2. A method for lubricating a cold pilger rolling mill according to claim 1, wherein the water-based emulsion formed by adding water to the cold pilger rolling water-soluble lubricant according to claim 1 is used for lubricating at least a material to be rolled and a roll die. A lubrication method for a cold pilger rolling mill, which is also used for cooling and lubrication of a roll shaft and a crank shaft.