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Any machinery will need a certain amount of lubricants, lubricants is the right-hand man of hydraulic motor pump, lubricant in large hydraulic motor pump as hydraulic transmission system in the middle of the medium, to play the role of a transfer of energy and conversion energy, at the same time in various parts of the hydraulic motor pump in the parts of lubrication, anti-corrosion, cooling, washing and so on has a special role.