It is very important to use roots vacuum unit correctly. In the process of use, we must master the use specifications and precautions to avoid loss caused by wrong operation. I will take you to understand it carefully
1. Roots vacuum unit preparation
(1) Operators must read the operating instructions of Roots vacuum unit.
(2) Before using roots vacuum unit products, make sure that there are no environmental factors that cause the products to be produced due to long-term storage.
(3) If abnormal sound and vibration are found during operation, the machine shall be shut down for troubleshooting.
(4) The enclosure of electrical equipment must be grounded or grounded.
2. Preparation of Roots vacuum unit before startup
(1) Check whether the liquid level in the water tank of the water flushing pump (front stage pump) reaches more than 3 / 4 of the water tank, and make up if it is insufficient.
(2) Check whether the water used in the water tank is clean, and do not use the sewage containing sediment to avoid blocking the pipeline, increasing the wear of the pump impeller, increasing the motor load and causing failure, affecting the service life of the water pump.
(3) Check the height of the lubricating oil level in the middle pump and the main pump, which must be more than 3 / 4 of the oil window, and check the color of the lubricating oil. If there are more opalescent or black impurities, inform the machine maintenance to replace the lubricating oil.
(4) Check whether the circulating cooling water circuit of intermediate pump and main pump is intact, open the inlet and outlet valves of circulating cooling water, and check whether the inlet and outlet water of circulating cooling water are normal.
(5) Check whether the blow down valve of buffer tank at the bottom of intermediate pump is closed.
(6) Check whether the circuit of vacuum pump unit is in good condition and all indications of control cabinet are normal.
(7) Check whether the starting pressure of intermediate pump and main pump of electrode contact pressure gauge of vacuum pump unit is normal (the starting inlet pressure of intermediate pump is more than 0.065mpa, and the starting inlet pressure of main pump is more than 0.085mpa).
(8) Start the vacuum unit after the above items are checked and confirmed to be correct.
3. Precautions for operation of Roots vacuum unit
(1) The sound response of Roots vacuum unit is uniform without noise and irregular abnormal vibration during operation.
(2) Pay attention to the motor load and the temperature rise of each part of the pump. Under normal conditions, the maximum temperature rise of the pump shall not exceed 40 ℃, and the maximum working temperature shall not exceed 80 ℃.
(3) In case of any oil leakage during the work, stop the work immediately and check and repair after pressure relief. It is not allowed to continue work or repair under pressure after finding the oil leakage.
(4) It is necessary to ensure the normal in and out of circulating cooling water during operation.
4. Roots vacuum unit start
(1) Open the inlet and outlet valves of circulating cooling water of intermediate pump and main pump to ensure the normal inlet and outlet of circulating cooling water.
(2) Close the blowdown valve of the surge tank of the water jet pump, start the water jet pump, and slowly open the valve on the bypass pipe of the front stage water jet pump and the intake valve of the roots vacuum pump after the operation is normal (noise from the motor and pump is balanced).
(3) When the system pressure reaches the allowable inlet pressure set by the intermediate pump, start the intermediate pump. If the automatic control gear is used, it will be directly shifted to the automatic control gear, and the starting process of the unit will be automatic.
(4) Such as manual control, when the outlet pressure of intermediate pump reaches the allowable inlet pressure of main pump, start the main pump.
5. Roots vacuum unit shutdown
(1) Put the control handle on the control cabinet of Roots vacuum unit into the manual gear, close the suction port valve of Roots vacuum pump and isolate it from the vacuum system.
(2) Stop the pump step by step according to the sequence of water flushing in front of the main pump and intermediate pump, and it is strictly prohibited to mistake the shutdown procedure.
(3) When the pre stage water flushing pump is stopped, the blowdown valve of the buffer tank of the water flushing pump shall be opened first, and then the pump shall be shut down.
(4) Close the inlet and outlet valves of circulating cooling water.
(5) Open the blowdown valve of the buffer tank under the intermediate pump to remove the oil and condensation water in it.
(6) If the pump is out of service for a long time or in severe cold season, the water in the clean water flushing pump box shall be discharged after the pump is stopped, and the drain plug of the water flushing pump body shall be turned to drain the water, so as to avoid frost crack of the box and pump body; similarly, the cooling water in the water jacket of the pump body of Roots vacuum pump shall be discharged to avoid frost crack.