JPH0135038B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a lubricant composition for metal processing, and more specifically to an emulsion-type rolling lubricant composition having excellent rolling properties and storage stability. Conventionally, emulsion-type lubricant compositions used in metal processing, such as rolling, and particularly in tene gauge rolling, which is said to be thin, have mainly been O/W emulsion-type compositions that use fats and oils as a base oil. This emulsion is then sprayed onto the comparatively high-temperature friction surfaces of the rolling rolls and the rolled metal material, and is destroyed by mechanical and thermal action, and the separated oil adheres to the metal material surface. It is believed that the lubricating effect is achieved by adsorbing pressure agents and the like. Therefore, in emulsion type lubricant compositions, the emulsion is easily destroyed during lubrication,
That is, although it is recognized that unstable emulsions exhibit better lubrication, in actual work, stable emulsions are required from the standpoint of storage and handling. Various studies have been conducted on emulsion-type rolling lubricant compositions. Literature on the phenomenon of emulsion failure in the lubricating action of rolling oil emulsions in hot and cold rolling, for example;
“Plasticity and Processing”, Vol.17, No.184 (1976-5), 433-
On page 444, one of the characteristics of emulsion lubrication is the destruction of emulsion, and it is reported that factors such as temperature and surfactants have a large influence on this destruction phenomenon. ”,
Volume 17, No. 3, pages 129-134, especially page 130 right column,
In the section "4. Conditions to be met by rolling oil" there is a description of the necessity of stability of rolling oil emulsion. As can be seen from the descriptions in these documents, emulsion-type rolling compositions are required to have the mutually contradictory requirements of easy emulsion breakability and good emulsion stability, but no efforts have yet been made to satisfactorily satisfy both of these conditions. No emulsion-type rolling lubricant composition has been obtained. In general, the HLB value of the emulsifier and the temperature of the emulsion have a large influence on the destruction of O/W emulsions, that is, the reversible phase inversion from O/W to W/O, but on the other hand, the type of oil and emulsifier Therefore, it is known that the temperature at which the phase changes (phase inversion temperature) is controlled. Recently, some attempts have been made to utilize the phase inversion phenomenon [for example, Japanese Lubrication Society Tohoku Conference Preprint p. 25 (October 7, 1970)]
[Japanese)] Simply undergoing phase inversion cannot be used as an actual rolling oil; it is essential that the phase inversion cycle occurs during rolling and during storage (in a tank), that is, reversible phase inversion. be. Focusing on the reversibility of this phase inversion, the present inventors have focused on the temperature range in which emulsion-type rolling lubricant plastics are actually used, that is, 40 to 20°C, and under tank storage conditions (low temperature, 40 to 60°C). In order to obtain a plastic lubricant for rolling that forms a stable O/W type emulsion under rolling conditions (high temperature, 100 to 200°C) and easily breaks the emulsion, we have conducted various researches and developed a certain type of lubricant. It has been discovered that the reversible phase inversion of the lubricant composition can be controlled and adjusted by adding certain compounds. In conventional emulsion-type rolling lubricant compositions that use fats and oils as a base oil, maintaining good emulsion stability improves storage stability during cyclic use, but rollability is extremely reduced, so It cannot be used as a lubricant for strict bearing gauge rolling, and on the other hand, if it is used with poor emulsion stability, rolling properties will improve, but the storage stability will be poor, and the active ingredients will be lost during cyclic use, resulting in a significant amount of oil consumption, making it economical. The losses are enormous. In the industry, there is no technology that satisfies these two requirements, so a method that only satisfies rollability at the expense of storage stability has been adopted, and the emergence of an emulsion-type rolling lubricant composition that meets both requirements. desired. However, according to research conducted by the present inventors, it has been found that the above problems can be solved by utilizing the phase transition phenomenon of the emulsion-type rolling lubricant composition as described above. Therefore, the present invention is based on controlling the reversible phase inversion of an emulsion-type lubricant composition. The rolling lubricant composition has a phase inversion cycle in which it becomes a W/O emulsion and returns to an O/W emulsion under tank storage conditions (40 to 60°C), thereby improving storage stability and rolling properties. The present invention was completed by confirming that both of the above performances were satisfied at the same time. According to the present invention, phase inversion adjustment is used because phase inversion is reversible depending on the environment in which the lubricant composition is placed as described above. A lubricant composition suitable for rolling that undergoes phase inversion at about 70°C is desired, but it has been found that such a lubricant composition can be obtained by using a specific emulsifier and a phase inversion modifier in combination. Ta. Therefore, the emulsion type rolling lubricant composition according to the present invention contains water, oil and fat, and the general formula () (In the formula, R represents a C ₆ to C ₁₂ alkyl group, and n
represents an integer from 2 to 9. ) and an emulsifier represented by the general formula () (In the formula, R′ is an alkenyl group with a molecular weight of 250 to 3000, R″ is an alkylene group having 2 to 4 carbon atoms, n
indicates 2 to 6. ) An emulsion-type rolling lubricating composition comprising a phase inversion modifier represented by: 50 to 99 parts by weight of oil and fat;
Emulsifier 0.1-15 parts by weight and phase inversion modifier 0.05-50
This is a lubricant composition obtained by diluting 100 parts by weight of a stock solution with water 2 to 200 times. The emulsion-type rolling lubricant composition of the present invention having desired phase inversion conditions can be obtained by mixing water, oil, fat, emulsifier, and phase inversion modifier in various proportions. The fats and oils used in the lubricant composition of the present invention are common animal and vegetable oils, such as palm oil, castor oil, coconut oil, rapeseed oil, soybean oil, fish oil, whale oil, beef tallow, lard, and mutton fat. The content of fats and oils in 100 parts by weight of the stock solution is 50 to 99 parts by weight. The emulsifier used in the lubricant composition of the present invention has the general formula () (In the formula, R represents a C ₆ to C ₁₂ alkyl group, and n
represents an integer from 2 to 9. ), specifically, polyoxyethylene octyl phenyl ether (n=3, 4, 5 and 7), polyoxyethylene nonyl phenyl ether (n=2, 3, 4, 5, 6, 7 and 8), etc. The phase inversion regulator used in the present invention has the general formula () (In the formula, R′ is an alkenyl group with a molecular weight of 250 to 3000, R″ is an alkylene group having 2 to 4 carbon atoms, n
indicates 2 to 6. ) is an alkenyl succinimide represented by
In particular, the preferred molecular weight range for R' is 400-2500. These can be used alone or in combination of two or more. These compounds can be obtained, for example, by the method described in Japanese Patent Publication No. 37-15778. In the present invention, various compounds that can be used in combination with the phase inversion modifier represented by the general formula () include the following. (1) _C8 to _C18 higher fatty acids and their esters such as lauric acid, palmitic acid, stearic acid, oleic acid, sorbitan monolaurate, sorbitan monopalmitate, oleic acid monoglyceride, oleic acid diglyceride, butyl laurate, butyl stearate,
Dioctyl adipate, dioctyl sebacate, etc. (2) Glycols, such as ethylene glycol,
Diethylene glycol, polyethylene glycol, etc. (3) Metal sulfonates, such as alkali metal or alkaline earth metal salts of petroleum sulfonic acids or common sulfonic acids, such as sodium dodecylbenzenesulfonate, sodium alkylnaphthalenesulfonate, and the like. (4) Nitrogen-containing compounds, such as polyoxyethylene alkylamines, alkylammonium chlorides, acid amides (for example, _C12 - _C30 linear or branched carboxylic acid amides), and the like. (5) Phosphorus or sulfur compounds, such as Zn, MO, W salts of dithiophosphoric acid, phosphoric acid esters, phosphorous acid esters, polysulfides, etc. (6) Mineral oil oxides or sulfides. For example, oxides with a saponification value of 20 mgKOH/g or more obtained by the oxidation reaction of mineral oil (mineral oil
150℃) or active sulfur obtained by sulfurization reaction of mineral oil.
0.02% (ASTM D-1662) sulfide (mineral oil reacted with elemental sulfur at 60-160°C is good). (7) Special mineral oils, that is, extracts obtained by solvent extraction of lubricating oil fractions obtained by vacuum distillation, with a %CA of 20% or more by the nd-M method. (8) Inorganic salts, such as CaCO ₃ , MgCO ₃ , Ca(PO ₄ ) ₂
Such. These phase inversion modifiers may be used singly or in combination of two or more, if desired, to obtain the general formula () of the present invention.
It can be used in combination with an alkenyl succinimide represented by The emulsion type rolling lubricant composition according to the present invention includes 50 to 99 parts by weight of oil and fat, and an emulsifier of the general formula ().
0.1 to 15 parts by weight, preferably 1 to 10 parts by weight, 0.05 to 50 parts by weight of a phase inversion modifier of general formula (), preferably
It can be obtained by diluting 100 parts by weight of a stock solution having a composition of 0.1 to 30 parts by weight with water 2 to 200 times, preferably 5 to 100 times. The emulsion-type rolling lubricant composition of the present invention (1) has excellent lubricity, with a large amount of oil adhering to the coil surface and roll surface during rolling. (2) Forms a dense and stable emulsion with good emulsification stability in a circulation tank, and active ingredients are not consumed during circulation. (3) It has advantages such as a small amount of scum produced and easy management of rolling oil, and exhibits extremely excellent performance as a lubricant composition for rolling. The present invention will be explained in more detail with reference to the following examples. Examples 94 parts by weight of beef tallow, 3.5 parts by weight of polyoxyethylene nonyl phenyl ether (n=4) of the general formula (), alkenyl succinimide of the general formula () (R': polybutenyl group with a molecular weight of 1000; R'': 20 to 100 parts by weight of a stock solution consisting of 2.5 parts by weight of "OLOA1200" (manufactured by Chevron Chemical Co., Ltd.) (ethylene group; n = 4)
An emulsion-type lubricant composition is prepared by mixing and emulsifying twice as much water. The lubricant composition thus prepared was tested on the following rolling mill and under the following rolling conditions. Rolling machine: Reversible precision two-high rolling mill (manufactured by Yoshida Dai-ni Kinen) Work roll specifications: 200φ×200W Central cooling type
Hardness, HS97 Material SUJ-2 Maximum rolling capacity: 40t Mill motor: 100 Tension: 70-500Kg Rolling speed: Maximum 200m/min Roll roughness: 0.4μmax Rolling conditions: Rolling agent: JIS-G-3141, 1.0mm x 50mm ×100m coil rolling speed: 200m/min Sample oil: 5% aqueous solution Reduction schedule (reduction rate for each pass): 10%
(1 pass) -30% (2 passes) -30% (3 passes) -30
% (4 passes) - 30% (5 passes) Oil supply amount: 5/min Evaluation was performed by calculating the friction coefficient using the commonly used Stone formula. However, the first pass is excluded because it is temper rolling. The results of the rolling test are shown in Table-1. For comparison, a similar test was also conducted using commercially available rolling oil. The product of the present invention exhibits excellent rollability comparable to that of a commercially available product made of beef tallow and an emulsifier.

[Table] Next, an emulsion stability test during storage was conducted. 400ml of sample oil was allowed to stand at 50℃ for 1 hour, stirred for 3 minutes at 8000 rpm using a homomixer, then allowed to stand for 8 minutes, and then turned upside down.
The oil content of a 100 ml layer was measured. Emulsion stability was evaluated from the value of α, where α=oil content in lower layer/oil content in upper layer. The larger the value of α, the better the emulsion stability. The results are shown in Table-2. It is clear that the product of the present invention has a large α and excellent emulsion stability.

[Table] Furthermore, a phase inversion cycle test was conducted to confirm the storage stability in a circulation tank due to reversible phase inversion. Pour 700% sample oil into a 1KL capacity tank, and heat the tank and the high temperature plate part of about 150℃ installed outside at 100% per minute.
The liquid was circulated for 60 days and scum in the tank liquid was observed. The oil temperature in the tank was maintained at 50°C. It can be seen that the product of the present invention has very little scum and has excellent emulsion stability in the tank due to reversible phase inversion. The commercially available product has a significantly large amount of scum, indicating a problem with emulsion stability. As explained in detail above, it is clear that the emulsion-type rolling lubricant composition according to the present invention has excellent rollability during rolling and also has excellent storage stability due to reversible phase inversion.

Claims (1)

[Claims] 1 Water, oil, general formula () (In the formula, R represents a C ₆ to C ₁₂ alkyl group, and n
represents an integer from 2 to 9. ) and an emulsifier represented by the general formula () (In the formula, R′ is an alkenyl group with a molecular weight of 250 to 3000, R″ is an alkylene group having 2 to 4 carbon atoms, n
indicates 2 to 6. ) An emulsion-type rolling lubricating composition comprising a phase inversion modifier represented by: 50 to 99 parts by weight of oil and fat;
Emulsifier 0.1-15 parts by weight and phase inversion modifier 0.05-50
A lubricant composition obtained by diluting 100 parts by weight of a stock solution with water 2 to 200 times.