Contact Us
TEL: +86-574-88350013
Mob: +8613003752008
Address: No.65, Mujin Road, National Hi-Tech Park, Ningbo, Zhejiang, China
Scientz-12ND Top-Press Multi-Pipeline Laboratory Freeze Dryer For Sale

Scientz-12ND Top-Press Multi-Pipeline Laboratory Freeze Dryer For Sale

ND series freeze dryer (electric heating type) ND 系列新图 FREEZE-DRYING SYSTEM The ND freeze-dryer adds heating to the N-series, accelerating the drying process, saving energy, and providing heating curve settings with a variety of drying solutions for laboratory use. This series of freeze dryer is...


   Several examples of lyophilizer maintenance Through long-term maintenance and maintenance of the lyophilizer, and continuous learning and practice in the work, accumulated a large number of maintenance experience, we will carefully observe, carefully analyze, and successfully processed The case is explained here.

 The lyophilizer mainly consists of advanced pharmaceutical equipment consisting of freeze-drying tanks, cold traps, refrigeration, vacuum, silicone oil circulation, and electrical control systems.


The general process of the lyophilization process is: before the product is put into the cabinet, the tank body and the slab layer are washed with water for injection;

 After being evacuated and dried, it is sterilized by pure steam;

 After opening the water ring vacuum pump to evacuate the drying box, the bellows leak rate detection is performed;

 After the leak rate is detected, the freeze-drying box is cooled, the product is put into the cabinet, and pre-frozen; sublimation drying, analytical drying; then the pressure rise test is performed to judge the lyophilization end time; finally, the deflation, discharge, and defrosting ends the batch. Freeze-drying process.


  1. The lyophilizer cannot verify the fault through the ultimate vacuum

  1. 1 Fault phenomenon The lyophilizer has a failure rate during pumping rate and ultimate vacuum re-validation: the pumping rate of the vacuum pump meets the verification requirements, and the lyophilizer and cold trap can be reduced from one atmosphere to less than 10 Pa in 30 minutes. The freeze-drying box can't fall below the 0.5Pa ultimate vacuum required by the verification, and can only be reduced to about 1Pa; the extended evacuation time can no longer reduce the vacuum. The normal situation should be: in the freeze-drying box heated to 35 ° C dry state, after the tank condenser is cooled to below -50 ° C, open the vacuum pump and the Roots pump to evacuate the freeze-drying box, at the same time start timing, in addition to the vacuum In addition to the evacuation rate of the vacuum pressure in the freeze-drying tank from one atmosphere to less than 10 Pa within 30 minutes, a stable vacuum of 0.5 Pa or less (20 minutes below 0.5 Pa) should be reached within 2 hours, and then closed. The septum valve calculates the leak rate of the tank after holding for 30 minutes.

  1.2 Fault Analysis and Processing This fault can generally be caused by three aspects:

1 vacuum pump failure, such as vacuum pump oil is contaminated, too much moisture in the vacuum pump oil can not cause sealing and lubrication or mechanical failure;

2 cases, pipes are not tightly sealed and there are leaking places;

3 The box is not sufficiently dry or has non-condensable substances. First, we will redo a SIP online sterilization process for the above third case. The drying stage will extend the drying time of the water ring pump and increase the temperature of the freeze-drying box to higher than 35 °C to ensure that the water in the box is completely dry and then re-applied. Verification, failure to pass verification to exclude the third case above. It was observed that the vacuum pump oil was dirty and the oil sample was released with more water. Therefore, the oil of the two Edward vacuum pumps was replaced, and all the pipes and joints connected to the vacuum pump were inspected, but it was not verified. However, the vacuum of the pump head can be directly applied to the pump head without a small disc valve, thereby achieving an ultimate vacuum of 0.5 Pa, thereby eliminating the first type of vacuum pump failure. Close the mushroom valve and only verify that the back box can reach the ultimate vacuum of 0.5 Pa or less to meet the verification requirements, thereby further narrowing the scope to the front box. For the front tank leak, the box door seal and all the seals associated with the front box were replaced with vacuum grease and all the pipes connected to the front box were sealed with blind plates, but they have not been verified. Enter the clean room and open the door to check that the board layer is intact and dry, but through careful inspection, the top layer connected to the bellows is found, and a blind plug is loose near the mushroom valve side. After the plug was removed and the packing was tightened, it was successfully verified. Analysis: Dongfulong freeze dryer does not heat and cool this layer, but the internal structure is the same as other layers. When CIP or SIP is used, moisture enters the cavity by loosening the plug, and the water is evaporated after high vacuum. The plug enters the front box to break the vacuum, causing the ultimate pressure not to be reached.


  2. Screw compressor exhaust temperature is too high


  2.1 Failure phenomenon

  During the production process, the freeze dryer alarms, and the fault is shown as 1# compressor discharge temperature is high. On-site inspection found that the screw compressor exhaust temperature was as high as 90 ° C, the normal temperature was about 60 ° C, and the alarm temperature was set to 85 ° C. However, the exhaust pressure is 12 bar, and the cooling system temperature of the 1# refrigeration system is -70 ° C, and the cooling is normal.


   2.2 Failure Analysis and Processing

 Since the suction and exhaust pressures and the cooling temperature of the refrigeration system are both normal, the leakage of the low-pressure refrigeration system is first excluded, resulting in an increase in the exhaust gas temperature. Then the cause of the high exhaust gas temperature may be the failure of the cooling system. The screw compressor refrigeration system, the oil circuit system and the compressor motor are all cooled by cooling water. Due to the normal discharge pressure and cooling water pressure, the compressor motor feels normal temperature by hand and the 2# refrigeration system has been operating normally, thereby eliminating the failure of the cooling water supply system. However, the oil temperature of the oil cooler enters and exits the oil temperature, but it is found that the oil temperature is high and the temperature difference between the inlet and outlet is small. It can be seen that the high exhaust gas temperature may be caused by the cooling of the oil cooling circuit, and the temperature of the lubricating oil separated by the oil separator is too high. High exhaust temperature,



Hot Tags: scientz-12nd top-press multi-pipeline laboratory freeze dryer for sale, China, factory, suppliers, wholesale, customized, buy, cheap, bulk, price list, for sale