Patent GB-818758-A (GB)
Title: Method and lubricant compositions for metal rolling
Inventor: LLOYD KENNETH ALAN
IPC: C23F11/14
Filed: 1956-09-07
Abstract: In rolling metals, lubrication and cooling of the pressure bearing surfaces are effected by a circulating aqueous lubricating composition comprising a major proportion of water and a minor proportion of a polyoxyalkylene liquid having a negative coefficient of solubility in water, the composition having a separation temperature between the temperature attained on the rolls and the lowest temperature in the circulation system.  The polyoxyalkylenes used are the polyoxyalkylene glycols and their monoor di-ethers or esters of the general formula R1O[R2O]n-R3, where R1 and R3 each represent hydrogen, a hydrocarbon radical or an acyl radical and R2 is alkylene and n an integer.  In the polyoxyalkylene chain the alkylene radical R2 may be of 2 to 8 carbon atoms and may be mixed, e.g. ethylene and propylene radicals may be present, in which case preferably at least 30 per cent of the radicals are propylene.  When R1 and/or R3 are hydrocarbon radicals they may be similar or dissimilar, saturated or unsaturated, straight chain or branched, non-aromatic radicals or substituted or unsubstituted aromatic radicals such as alkylphenyl.  When R1 and/or R3 are acyl they are preferably derived from alkane or alkene monocarboxylic acids. Molecular weights of 350-10,000 can be employed.  Representative are the polyoxyalkylene glycol mono-alkyl ethers containing oxyethylene and oxypropylene units available commercially under the Registered Trade Mark "Ucon" and the polyoxyethylene glycol monoalkylphenyl ethers obtainable under the Registered Trade Mark "Igepal" particularly the butyl monoether of a block copolymer containing equal weights of ethylene and propylene oxides, the butyl monoether of a copolymer containing by weight 60 per cent ethylene oxide and 40 per cent propylene oxide and the octylphenyl ether of polyoxyethylene glycol containing an average of 9 ethylene oxide radicals per molecule and polyoxyethylene glycol monolaurate.  The separation temperature depends on the temperature of the rolling mill but may be for example from 35-99 DEG  C.  When the liquid is on the rolls preferably 0.5-5 per cent by weight of the composition is in a separate oily phase.  The composition may contain 2-20 per cent by weight of polyoxyalkylene compound but may be stored and transported in more concentrated solutions.  A surface-active agent may be present as an emulsion stabilizer which must pass an emulsion stabilization test described.  Preferred are 0.05-2 per cent by weight of the composition of secondary alkyl sulphates, or alkali or alkaline-earth metal salts of organic sulphonic acids particularly petroleum sulphonates.  Other additives include corrosion inhibitors, e.g. sodium nitrite, potassium chromate, disodium hydrogen phosphate, triethanolamine, alkali metal mercaptobenzthiazoles and oleic acid, alkali and alkaline earth metal salts of organic sulphonic acids also act as corrosion inhibitors and if present as an emulsion stabilizer further corrosion inhibitor may be unnecessary; and anti-foaming agents such as the organo-silicone polymers.  The lubricants are useful in the rolling of steel or aluminium (see Group XXII).