Blog
电动执行器的维修和保养(电动执行器)
发布时间:2020-07-28 15:13:13

Common faults and elimination methods of electric actuators

malfunction

the reason

elimination method

1. The motor cannot start

1. Power failure or lack of phase

1. Check the power supply

2. Low power supply voltage

1. Check the voltage

3. The action of the overheat protection switch embedded in the motor coil (motor overheating)

3. See if the fault can be eliminated after the motor temperature drops

4. The valve or actuator itself is stuck

4. Try manual operation with actuator handwheel

2. The motor stops during the switch operation

1. The load is too large, so that the force protection switch acts

1. Try to increase the setting value of torque protection

2. The action of the overheat protection switch embedded in the motor coil (motor overheating)

2. See if the fault can be eliminated after the motor temperature drops

3. Control circuit board failure

3. Replace the circuit board

3. The electrical limit switch cannot limit

1. Motor reverse

1. Try to replace the motor wiring, or replace the split-phase capacitor, otherwise replace the motor

2. The limit switch is damaged

2. Replacement limit development

3. The limit position is not adjusted

3. Readjust

4. The circuit board is damaged

4. Replace the circuit board

4. The motor runs but the valve does not move

1. The switching mechanism is abnormal

1. Disassembly inspection

2. Connection problems

2. Check the connection

Fifth, do not move manually

1. The switching device is not closed

1. Switching device

2. Mechanical stuck

2. Eliminate the cause of the death

Six, valve stem vibration at startup

The stem nut is loose or improperly tightened

Remove the stem cover or pipe plug and tighten the lock nut

7. Poor insulation

Into the rain (poor sealing of the wire inlet)

1. Repair sealing parts

2. Drying electrical components and motors

3. Pay attention to the cable inlet seal

8. Oil leakage

1. Damaged seal

1. Check and repair the seal

2.The ambient temperature is high, and the internal pressure of the main box increases

2. Loosen the screws that do not affect the work, (preferably oil plug) exhaust

Nine, on-site control is normal, remote control is not

1. The circuit board is damaged

1. Replace the circuit board

2. The control signal line is damaged

2. Check the control signal cable

3. The control signal is connected incorrectly

3. Check the wiring

Ten, on-site control is normal, the remote control valve position display disappears

1. The position sensor is broken

1. Check the sensor

2. Itinerary is not set

2. Reset the itinerary

3. The circuit board is broken

3. Replace the circuit board

11. One-way action

1. Circuit board failure

1. Replace the circuit board

2、One-way limit

2. Re-adjust the limit

3、Damaged motor

3. Replace the motor


Maintenance and maintenance of electric actuators (electric actuators):

Electric actuators (electric actuators) are electromechanical integration products, mainly composed of motors, bearings, gear transmission systems and electronic parts. According to the reliability data published by the US military standard MIL-HDBK-338, mechanical failures of electric actuators (electric actuators) are mainly concentrated on bearings. In terms of electrical appliances, the problem is mainly on the control circuit board, and sometimes the motor also fails. Among the motor failures: winding failure accounts for 20%, bearing failure accounts for 45%, and slip ring, brush, and commutator damage accounts for 5%. Others account for 30%; in bearing failures: lubricant deterioration and disappearance account for 45%, pollution account for 30%, erosion account for 5%, misadjustment accounts for 5%, corrosion accounts for 5%, others account for 10%. It can be seen that good maintenance management can improve the reliability and effectiveness of electric actuators.

1. Strengthen the cleanliness management of lubricating oil The biggest feature of electric actuators is the need to use lubricating oil, whose viscosity changes with oil temperature. If the viscosity is too low, the wear of the transmission components such as the turbine worm and gear will increase, which will reduce the transmission accuracy; if the viscosity is too high, the action will be bad. The management of the cleanliness of lubricating greases is more difficult. The wear of turbine worms and gears, the penetration of impurities and moisture generated by aging, the shedding of internal coatings, and corrosion will affect the cleanliness of lubricating oil.

2. Eliminate the leakage of lubricating grease in time. Due to the high operating frequency and speed of the electric actuator (electric actuator), it is difficult to avoid impact. This is an important reason for the leakage of lubricating grease. Once the lubricating grease leaks, it needs to be resolved in time.

3. Improve the working environment and operating conditions of electric actuators (electric actuators). The reliability and life of electric actuators (electric actuators) are directly related to its use, environment, personnel knowledge and other factors. Only by improving its working environment and conditions of use in maintenance and management, and putting people first, can it extend its service life.

4. Special maintenance should be strengthened in the early stage of the failure. Among all the failures of the electric actuators, the proportion of the initial failures is generally relatively high. Most of the initial faults are caused by preliminary errors in design, manufacturing, and installation. The discovery of these initial faults requires a certain amount of effort, and it takes time to solve them. Therefore, maintenance management should be strengthened during the initial failure period.

5. Do a good job of data management to prevent accidental failures of electric actuators (electric actuators) are generally difficult to predict. In order to prevent sporadic failures, it is necessary to regularly check and maintain, and master the maintenance data and historical file data at a certain stage, which is very important for the accurate implementation of failure judgment and daily maintenance.

6. Improve the professional knowledge of the operation and maintenance personnel The mastery of the professional knowledge of the operation and maintenance personnel directly affects the maintenance management. In recent years, due to changes in the structure of operation and maintenance personnel, they have greatly improved their knowledge and technology of electric actuators. However, many operation and maintenance personnel still lack the professional knowledge and technology they deserve. Most of the on-site operation and maintenance personnel are in a state of "seemingly understand but not understanding" about electric actuators, which is also the weak link of maintenance management. In order to facilitate the operation and maintenance personnel to carry out on-site maintenance and management, we must have advanced awareness in the design of electric actuator systems, fully consider the implementation of maintenance and management, and strive to achieve: the system should be simplified, the simple system failure rate is low, and maintenance management Easy; high degree of standardization, good interchangeability, easy to repair; integration, combination, convenient adjustment and inspection; introduction of new technologies such as fault diagnosis and positioning, fault tolerance/correction.

7. Since the control circuits of electric actuators (electric actuators) are damaged most, it is necessary to increase the service life of the control circuit board, and the control circuit boards of electric actuators (electric actuators) are damaged greatly. Most of them are caused by water ingress or dampness, and the ambient temperature is too high. Therefore, it is necessary to ensure that the electric control room of the electric actuator (electric actuator) is well sealed, and try not to let water get in. Try to make a canopy for the electric actuator (electric actuator) if possible. Most actuators can only reach IP67, this protection can only be drenched in the rain for a short time and cannot be exposed to heavy rain.