Food freeze dryer maintenance and repair

　　We all know clearly that the maintenance and repair of food freeze dryers is composed of two parts: the refrigeration system and the vacuum system. The principle is that when the items to be added are placed in a low-temperature vacuum environment, the water contained therein is frozen into ice. The ice sublimates into water vapor under low pressure and is pumped out by the vacuum pump, thereby drying the items to be processed. Then we can come to the conclusion that the refrigeration system and vacuum system are the brains of food freeze dryer maintenance and repair. As long as there is a problem with one of them, it will not function and work properly. Therefore, the daily maintenance of the freeze dryer is very important. Therefore, we need to perform regular maintenance and repairs on the food freeze dryer, so this time we will further explain the maintenance work of these two systems.

　　1. Maintenance of refrigeration system

　　The refrigeration system of the freeze dryer is mainly composed of a compressor, expansion valve, water-cooled condenser, evaporator, oil separator, gas-liquid separator, solenoid valve, hand valve, pressure gauge, pressure controller, drying filter, etc.

　　The main contents of daily maintenance are as follows:

　　1. Daily routine inspection. The main inspection contents include:

　　2. Whether all valves that should be opened are open.

　　3. Check whether the compressor pressure is within the normal range.

　　4. Are the pressure and temperature of the cooling water normal?

　　5. Whether the compressor oil return and oil level are normal.

　　6. Whether the compressor operation sound is normal.

　　7. Whether there is abnormal vibration in the refrigeration pipeline.

　　8. Frosting of the compressor and expansion valve, etc.

　　9. If any abnormality is found during the inspection, the cause should be found out and handled in time to eliminate potential accidents.

　　10. When the equipment is not used for a long time, the refrigerant should be collected into the condenser to prevent refrigerant leakage. During the production process, the refrigeration system should be checked for leaks frequently to ensure that leaks are discovered and dealt with promptly. If the refrigerant is insufficient, it should be filled in time to avoid affecting the normal operation of the equipment.

　　2. Maintenance of vacuum system

　　The vacuum system is mainly composed of a vacuum pump, a front box, a back box, valves on the box, mushroom valves, small butterfly valves, vacuum silicon tubes, etc.

　　1. Replace the vacuum pump oil regularly to ensure the performance of the vacuum pump.

　　2. Before starting the vacuum pump, check whether the oil level is normal (it should be about 1/2 of the oil sight glass).

　　3. Before vacuuming the box, make sure the back box is dry to avoid drawing water vapor into the pump body, which will affect the pumping efficiency of the vacuum pump.

　　4. Nowadays, freeze dryers are used for drying in many fields. As a new drying method, there is no doubt that the drying effect of food freeze dryers is the best. Because of the retention of the ingredients of the material, as well as the effect of later preservation and rehydration, freeze drying can achieve almost perfect retention of the original material properties.

　　5. Food freeze dryer maintenance and repair mainly consists of electronic control system, refrigeration system, vacuum system and some spare parts. Below we will first talk about some maintenance of the vacuum system:

　　6. The vacuum system is one of the important components of the maintenance and repair of the food freeze dryer. It generally includes a rotary vane vacuum pump or a dry pump and a Roots pump to accelerate vacuuming.

　　7. Last time I talked about the inspection of the vacuum pump during operation. This time I will explain the inspection and maintenance of the vacuum system of the freeze dryer that has been out of operation for a long time.

　　3. Vacuum pump maintenance

　　1. If the pump is not used for a period of time, the power supply and cooling water supply should be turned off;

　　2. If the pump is turned off directly after the freeze-drying process, water vapor may remain in the pump body. If the pump is shut down for an extended period of time, these liquids may corrode the pump's mechanical structure and may prevent the pump from starting again. It is recommended that the pump be idle for about half an hour after debugging.

　　3. The pump head valve is powered when the vacuum pump is turned on, and is powered off when the vacuum pump is stopped;

　　4. Whether the pump head valve is powered or not can be judged from the air inlet at the end of the valve. Remove the muffler and block the air inlet with your hands. If air is sucked in, it proves that the valve is not powered, and vice versa;

　　5. Turn off the vacuum pump and cut off the power supply of the pump head valve. Use the change in vacuum degree of the silicon tube on the vacuum tube to determine whether the pump head valve is closed tightly.

　　We will briefly introduce the maintenance and repair of food freeze dryers here. If you need more information, please contact our staff.

Related recommendations