1: thermal deformation of the machine
The moving parts with different coefficients of thermal expansion in the hydraulic components are stuck due to their smaller fitting clearances, causing malfunctions, affecting the transmission accuracy of the hydraulic system, and deteriorating the working quality of the parts.
2: reduce the viscosity of the oil
Excessive temperature rise of the injection molding machine will cause the viscosity of the oil to decrease, the leakage increases, and the volumetric efficiency of the pump and the efficiency of the entire system will be significantly reduced. As the viscosity of the oil decreases, the oil film of the sliding valve and other moving parts becomes thinner and cut, and the frictional resistance increases, resulting in increased wear.
3: Deformation of rubber seals
Excessive temperature rise of the injection molding machine will deform the rubber seals, accelerate the aging failure, reduce the sealing performance and service life, and cause leakage.
4: Accelerate the oxidation and deterioration of oil
Excessive temperature rise of the injection molding machine will accelerate the oxidative deterioration of the oil, precipitate bituminous substances, and reduce the service life of the hydraulic oil. The precipitates block the damping orifice and the slit valve port, causing the pressure valve to become stuck and unable to move, and the metal pipe is stretched and bent, or even ruptured.
5: lead to poor work quality of components
Excessive temperature rise of the injection molding machine will cause the quality of the parts to deteriorate, and the dissolved air in the oil will escape, resulting in air pockets, which will reduce the working performance of the hydraulic system. The ideal working temperature of the hydraulic system should be between 45 degrees and 50 degrees. The reason is that the hydraulic system is designed according to a selected pressure oil viscosity, but the viscosity will change with the oil temperature, which will affect the work in the system. Components, such as oil cylinders, hydraulic valves, etc., reduce control accuracy and response sensitivity, especially for precision injection machines. At the same time, if the temperature is too high, it will accelerate the aging of the seal and cause it to harden and crack; if the temperature is too low, the processing energy will be consumed and the operating speed will be reduced. Therefore, it is necessary to pay close attention to the working temperature of hydraulic oil. There are many reasons for the high oil temperature, but most of them are due to the failure of the oil circuit or the failure of the cooling system.