Hydraulic systems and lubrication systems are an important part of each mechanical device. The hydraulic system needs to maintain high pressure at work and generate a lot of heat, and the oil temperature rises after a long period of time. If there is no timely discharge of heat, will lead to the system of sealing components aging, damage, and oil viscosity with the oil temperature rise and low, the oil pressure is also less than the requirements of the work. To ensure safe and reliable operation of the unit. The oil temperature must be controlled within the specified range. The main reason for the oil temperature rise of the lubrication system is different from that of the hydraulic system, but it is also necessary to control the oil temperature within the specified range.