High hydraulic (grab) oil temperature will directly accelerate the deterioration of hydraulic oil and shorten the service life of oil. The principle of electro-hydraulic grab is to work the electric energy through the hydraulic system to realize the opening and closing of grab and achieve the purpose of loading and unloading goods.
  Working condition 1 causing oil temperature rise: the electro-hydraulic grab bucket with unreasonable design. When grasping materials, once the material resistance is greater than the excavation force of the grab bucket, although the grab bucket can not grasp the materials and "suffocate" in the material pile, the motor of the grab bucket still rotates, and even the motor is "locked". In order to protect itself, the hydraulic system is equipped with overflow valve, At this time, the pump overflows under high pressure through the overflow valve, and the oil temperature rises sharply. Energy is conserved. Electric energy becomes heat energy to heat the oil.
  Working condition 2 causing oil temperature rise: the electro-hydraulic grab with unreasonable design. During loading and unloading, due to the operators experience or sight and other factors, continue to press and hold the handle after the hydraulic grab is closed to close the grab again (often occurs). At this time, the motor of the grab still rotates, the motor is "locked", and the hydraulic pump overflows under high pressure through the overflow valve, The oil temperature rises sharply. Energy is conserved, and electric energy becomes heat energy to heat the oil.
  1. The operation of hydraulic grab is not feasible and safe. The high oil temperature of hydraulic grab bucket will cause hazards, such as the decrease of hydraulic oil viscosity, volumetric efficiency and working efficiency of hydraulic system, the increase of leakage, the inability to maintain the pressure, the small grasping force or the inability to grasp the goods in light cases, and the poor reliability. The goods in heavy cases will fall in the air, which is unsafe.
  2. Affect production. The high oil temperature of hydraulic grab affects the efficiency of loading and unloading.
  3. The parts of the hydraulic system expand due to overheating, which destroys the original normal fit clearance of the relative moving parts, resulting in increased friction resistance and easy jamming of the hydraulic valve. At the same time, it thins the lubricating oil film and increases mechanical wear. As a result, the precision fit surfaces of pumps, valves and motors become invalid or scrapped due to premature wear.