The vacuum dryer system consists of refrigeration system, vacuum system, heating system and electrical instrument control system. The main components are drying boxes, condensers, refrigerating units, vacuum pumps, heating / cooling devices, etc. The process of vacuum drying is to place the drying material in an airtight drying chamber and heat the drying material continuously while vacuuming with a vacuum system, so that the moisture in the material can diffuse to the surface through pressure difference or concentration difference. The water molecule can obtain enough kinetic energy on the surface of the material and overcome the mutual attraction between the molecules. Escape to the low pressure space of the vacuum chamber and thus be evacuated by the vacuum pump. Vacuum pump is the most important part of vacuum drying, so what are the precautions for the use of vacuum pump in vacuum dryer? Let’s get to know it together.
vacuum dryer system
1. Generally speaking, the vacuum pump of vacuum dryer should be repaired after 2000 hours’operation to check the aging degree of the gum seals, check whether the exhaust valve sheet is cracked, and clean up the dirt deposited on the valve sheet and the exhaust valve seat. Clean parts of the entire vacuum chamber, such as rotor, rotary vane, spring and so on. Usually wash and dry with petrol. After cleaning the rubber parts, dry them with dry cloth. When cleaning and assembling, handle with care gently and carefully.
2, conditional cleaning of the vacuum dryer tube to ensure smooth pipeline.
3, check the vacuum dryer vacuum pump pipeline and whether there is loose junction. Turn the vacuum pump by hand to see if the vacuum pump is flexible.
4. Check the oil level regularly. If it does not meet the requirements, it must be adjusted to meet the requirements. When the vacuum pump is running, the oil level will go to the oil standard center.
5. Check the oil quality frequently and find that the new oil should be replaced in time to ensure that the vacuum pump works normally. Vacuum dryer vacuum pump in the first month of work, after 100 hours to replace lubricants, after each 500 hours, oil change once.
6. The time limit for oil exchange shall be determined by the user at his discretion according to the actual operating conditions and whether the performance requirements can be met or not. When the new vacuum pump is used to remove clean and dry gas, it is recommended to change the oil once every 100 hours. After the black metal powder is not seen in the oil, the oil transfer period can be extended appropriately.
7. Add bearing lubricating oil to the bearing body. Observe the oil level at the center line of the oil mark. The lubricating oil should be replaced or supplemented in time.
8. Trial operation should be carried out after reassembly. Usually, it should run empty for 2 hours and change oil twice. Because there will be a certain amount of volatile substances in the vacuum pump when cleaning, and then put into normal work after normal operation.
9, point motor, see if the motor is turning correctly.
10. Screw down the water plugs of the vacuum pump body of the vacuum dryer and pour into the water (or draw the pulp).
11. Close the gate valve and outlet pressure gauge of the outlet pipe and the imported vacuum gauge.
12. Turn on the motor. When the vacuum pump is in normal operation, open the outlet pressure gauge and the import vacuum pump. After it shows the appropriate pressure, gradually open the gate valve and check the load of the motor.
13. Controlling the flow rate and head of the vacuum pump of the vacuum dryer as far as possible within the range indicated on the label to ensure the operation of the vacuum pump at the most efficient point can achieve the greatest energy-saving effect.
14. During the operation of vacuum pump of vacuum dryer, the bearing temperature should not exceed 35C and the maximum temperature should not exceed 80C.
15. If there is abnormal sound in the vacuum dryer, check the reason immediately.
16. To stop the use of vacuum pump in vacuum dryer, first close gate valve and pressure gauge, and then stop motor.
17. Adjust the packing gland regularly to ensure that the leakage in the packing room is normal.
18, regularly check the wear of the axle sleeve, and replace it in time when the wear is large.
19. When the vacuum pump of the vacuum dryer is used in the cold winter season, after stopping, it is necessary to unscrew the bolt at the lower part of the pump body to remove the medium. Prevent frost crack.
20. Vacuum pump of vacuum dryer is out of service for a long time. It is necessary to dismantle all the pumps, dry the water, coat the rotating parts and joints with grease, and keep them properly.
Above is the overall content of the matters needing attention in the use of vacuum pumps in dryers. It is necessary to use the vacuum machinery correctly in order to maximize the benefits.
Rotary Vane Vacuum Pump