How to solve the problem of heating of injection molding machine?

Causes of heating of injection molding machine

(1) The volume of the oil tank is too small, the heat dissipation area is not enough, and the capacity of the cooling device is too small.

(2) When the oil supply system of quantitative pump is working, some excess flow will overflow back from the overflow valve under high pressure and generate heat.

(3) When the unloading circuit in the system fails or the unloading circuit is not set, the oil pump cannot unload when it stops working. All the flow of the pump overflows under high pressure, resulting in overflow loss and heating, resulting in temperature rise.

(4) The system pipeline is too thin, too long, too many bends, and the local pressure loss and pressure loss along the way are large.

(5) The accuracy of components is not enough and the assembly quality is poor, and the mechanical friction loss between relative movements is large.

(6) The fitting clearance of fitting parts is too small, or the clearance is too large and the internal and external leakage is large after wear and tear.

(7) The working pressure of the hydraulic system is adjusted much higher than the actual need. Sometimes because the seal is too tight, or because the seal is damaged and the leakage increases, the pressure has to be increased to work.

(8) The temperature of the climate and working environment is high, resulting in the rise of the oil temperature.

(9) If the viscosity of the selected oil is improper, the viscosity is large, the viscous resistance is large, and if the viscosity is too small, the leakage will increase. Both cases can cause heating and temperature rise.

Harm of high temperature rise of high speed injection molding machine

(1) Make the machinery produce thermal deformation, and the moving parts with different thermal expansion coefficients in the hydraulic components cause action failure due to their smaller matching clearance, which affects the transmission accuracy of the hydraulic system and leads to the deterioration of the working quality of the parts.

(2) Reduce the viscosity of the oil, increase the leakage, and significantly reduce the volumetric efficiency of the pump and the efficiency of the whole system. As the viscosity of the oil decreases, the oil film of moving parts such as slide valve becomes thinner and the friction resistance increases, resulting in increased wear.

(3) Deform the rubber seal, accelerate aging and failure, reduce sealing performance and service life, and cause leakage.

(4) Accelerate the oxidation and deterioration of oil, and precipitate asphalt materials, so as to reduce the service life of hydraulic oil. The precipitate blocks the damping small hole and slit valve port, resulting in the failure of the pressure valve, the elongation and bending of the metal pipeline, or even rupture.

(5) The air separation pressure of the oil is reduced, and the dissolved air in the oil escapes, resulting in cavitation, which reduces the working performance of the hydraulic system.

Cooling method of injection molding machine

(1) According to different load requirements, often check and adjust the pressure of the overflow valve to make it just right.

(2) Reasonably select hydraulic oil, especially oil viscosity. If conditions permit, try to use a lower viscosity to reduce viscosity friction loss.

(3) Improve the lubrication conditions of moving parts to reduce friction loss, which is conducive to reducing working load and heating.

(4) Improve the assembly quality and accuracy of hydraulic components and hydraulic system, strictly control the matching clearance of mating parts, and improve the lubrication conditions. Adopt the sealing material with small friction coefficient, improve the sealing structure, and reduce the starting force of the hydraulic cylinder as much as possible, so as to reduce the heat generated by mechanical friction loss.