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Freeze Dryer Vacuum System Common Fault
- Jul 24, 2017 -

Advantages of freeze dryer:

1, many heat-sensitive substances will not be degeneration or inactivation;

2, at low temperature drying, the material in some of the volatile components of the loss is small;

3, in the freeze-drying process, the growth of microorganisms and the role of enzymes can not be carried out, so to maintain the original traits;

4, because in the frozen state of drying, so the volume is almost unchanged, to maintain the original structure, will not occur concentrated phenomenon;

5, because the material in the water after the pre-freeze in the form of ice crystals, the original dissolved in water in the inorganic salt dissolved substances are evenly distributed in the material;

6, after drying the material loose porous, sponge-like, dissolved after the water quickly and completely, almost immediately restore the original traits;

7, because the drying in the vacuum, oxygen is very small, so some easy to oxidize the material has been protected.

1. Freeze Dryer vacuum system vacuum is not high. Cause: Pump temperature is too high, may be pump valve or cavity scratch wear, rotor shaft displacement caused by single-sided wear. Pump oil problems: oil level is too low, the seal is not strict; oil pollution was yellow; oil level normal, oil barrier, pump cavity did not maintain the appropriate amount of oil. Pump itself leaks: seals, gas needle washers are damaged or not pressed, the exhaust valve is damaged, resulting in poor sealing. The air inlet filter is blocked. Remedy: Reassemble after repair. Refueling; oil change; check the oil and oil valve into the oil. Replace the seal or valve for specific conditions. Remove the cleaning.

2. Freeze dryer vacuum system motor overload operation, the pump running abnormal noise, noise, rotation difficult. Cause: Pump temperature is too high, may be pump valve or cavity scratch wear, rotor shaft displacement caused by single-sided wear. Spring deformation or fracture, so that the rotation of the rotor is not uniform and the impact of sound. The filter is damaged and the crumbs fall into the pump. Pump cavity pollution is serious, parts rust. Pump chamber shaft and sleeve with too tight, resulting in poor lubrication. Remedy: Reassemble after repair, replace the spring, remove the cleaning, oil change, re-assembly, and clear the oil.

3. freeze dryer vacuum system oil spill, fuel injection. Cause: The shaft, oil window, oil hole and other parts of the seal damage or assembly is not correct. The inlet pressure is too high. Excessive fuel, resulting in fuel injection. Exhaust cover below the oil net installed anti, causing fuel injection. Remedy: Replace the seal or reassemble, try to reduce the amount of oil, release part of the oil, reassemble.