Causes and Solutions for Motor Burnout in the Hydraulic System of Powder Forming Hydraulic Press
1. Reason for Motor Burnout: Due to prolonged overload or overheating operation, the insulation of the winding of the hydraulic system motor in the powder forming hydraulic press ages, and weak points in the insulation undergo carbonization, leading to phenomena such as inter-turn short circuits, inter-phase short circuits, or ground short circuits, resulting in localized burning of the winding.
Solution:
- 1.Avoid prolonged overload operation of the motor.
- 2.Ensure cleanliness and good ventilation for the motor.
- 3.Minimize frequent motor starts, and conduct dynamic balancing tests on the rotor of the hydraulic system motor when necessary.
2. Operation with Missing Phase: In this case, the hydraulic system motor of the multifunctional hydraulic press produces loud noise, severe heating, and is prone to burning within a short operating time. If the entire power supply system has a missing phase, it can potentially damage multiple motors in the hydraulic system. The missing phase often results in burnt phases, either one or two. Single-phase operation occurs due to an open circuit in one phase of the motor power supply, often caused by a burnt fuse, faulty electromagnetic contactor, a disconnected power line, or poor wiring.
Solution: Various protection methods and devices, such as thermal relays with phase loss protection, reverse current relays for phase loss protection, zero-sequence voltage relays for phase loss protection, and broken wire voltage relays for phase loss protection, can be used.
3. Winding Insulation Damage due to Mechanical Vibration: Mechanical vibrations, such as large current shocks during startup and rotor imbalance of the motor in the hydraulic system of the powder forming hydraulic press, cause inter-turn loosening and insulation cracking in the winding. Continuous accumulation of these effects, along with thermal expansion and contraction, leads to friction in the winding, accelerating insulation aging and eventually causing localized burning of the winding.
Solution:
- 1.Minimize frequent starts, especially for the hydraulic system motor in the powder forming hydraulic press.
- 2.Ensure that the vibration values of the driven equipment and the motor are within the specified range.
4. Poor Motor Seal: Leakage into the motor can corrode the winding insulation, leading to localized burning of the hydraulic system motor in the powder forming hydraulic press.
Solution:
- 1.Eliminate equipment leaks as much as possible.
- 2.Pay attention to the sealing of each part of the hydraulic system motor during maintenance, such as applying a small amount of 704 sealant to flanges and applying grease to bolts.
5. Bearing Damage and Shaft Misalignment: Bearing damage or shaft bending can cause friction between the stator and rotor (commonly known as "sweeping the flue"), leading to a sharp rise in the iron core temperature, burning of slot insulation, inter-turn insulation, and causing short circuits. Severe cases can result in stator core slotting, misalignment, shaft wear, and scrapped end covers.
Solution:
- 1.Heat the bearing to 80°C~100°C before disassembling it.
- 2.Thoroughly clean the bearing before installation, ensuring no impurities in the bearing chamber, and ensure cleanliness when adding grease.
- 3.Avoid unnecessary machining of the shaft and nesting of the end cover of the hydraulic system motor.
- 4.Ensure proper alignment of the stator and rotor cores during the assembly of the hydraulic system motor.
- 5.Maintain cleanliness of the motor casing, ensure ventilation, and keep the cooling device free of dirt.
- 6.Avoid mixing different lubricants.
- 7.Perform a comprehensive and detailed inspection of the bearing before installation.
- 8.For hydraulic system motors not used for an extended period, conduct necessary disassembly inspections and update the bearing grease before use.