Hazards of oil temperature rise in the hottest ele

  • Detail

The high temperature of electric hydraulic grab oil is caused by the unreasonable design of hydraulic system or the backward and imperfect technology

the principle of electro-hydraulic grab is to use electric energy to work through the hydraulic system to realize the opening and closing of grab and achieve the purpose of loading and unloading goods

working condition 1, which causes the oil temperature to rise, is the unreasonable design of the electro-hydraulic grab. When grasping the material, once the material resistance is greater than the excavation force of the grab, although the grab can't grasp the material and "suffocate" in the material pile, the motor of the grab still rotates, and even the motor has a "locked rotor". In order to protect itself, the hydraulic system is equipped with an overflow valve. At this time, the pump overflows through the overflow valve under high pressure, and the oil temperature rises sharply. Energy is conserved. Electric energy turns into heat energy to heat the oil

working condition 2, which causes the oil temperature to rise, is the unreasonable design of the electro-hydraulic grab. During loading and unloading operations, due to the operator's experience or sight and other factors, continue to press and hold the handle after the grab is closed, so that the grab is closed again (often occurs). At this time, the grab motor is still rotating, the motor appears "locked rotor", the hydraulic pump overflows through the overflow valve with high pressure, and the oil temperature rises sharply. Energy is conserved, and electric energy turns into heat energy to heat the oil

detailed analysis: the rise of oil temperature not only wastes energy, but also causes the following hazards:

1 Grab work is not examinable and unsafe. The oil temperature rises sharply, the hydraulic oil viscosity, volumetric efficiency and the working efficiency of the hydraulic system decrease, the leakage increases, the pressure can not be maintained, the light person's grasp force becomes smaller or cannot grasp the goods, the reliability is poor, and the heavy person's grasp of the goods falls in the air, which is unsafe

2. Affect production. Due to the above 1 situation, the user had to stop and let the oil temperature of the grab cool down, which affected the efficiency of loading and unloading

3. The parts of the hydraulic system expand due to overheating, which destroys the original normal fitting 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 fitting surfaces of pumps, valves, motors, etc. become invalid or scrapped due to premature wear

4. Vaporization of oil and water will easily cause cavitation of hydraulic components and will continue to participate in relevant research and corrosion; The oil oxidizes to form colloidal deposits, which are easy to block the small holes in the oil filter and hydraulic valve, making the hydraulic system unable to work normally. The market trend of flame retardants for plastics, rubber and textiles is to require the use of halogen-free flame retardants to achieve low smoke characteristics

5. Accelerate the aging and deterioration of rubber seals, shorten their service life, and even lose their sealing performance, causing serious leakage of the hydraulic system

6. Too high oil temperature will accelerate the deterioration of hydraulic oil and shorten the service life of oil

7 Grab failure rate is high and maintenance cost increases. High oil temperature will seriously affect the normal use of the machine, reduce the service life of hydraulic components, and increase the maintenance cost due to high failure rate

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