Some simple maintenance methods of Sihuan freeze-drying pharmaceutical freeze dryer

The four-ring freeze-drying pharmaceutical freeze-drying machine is composed of two parts: a refrigeration system and a vacuum system.
Through the physical principle, the humid and high temperature compressed air flows into the pre-cooler, and then flows into the heat exchanger after dissipating heat; the air discharged from the evaporator The cold air exchanges heat and reduces the temperature of the compressed air entering the evaporator
.

Sihuan freeze-drying pharmaceutical freeze-drying machine is suitable for drying materials such as medicine, Chinese medicine decoction pieces, seafood, wild vegetables, dehydrated vegetables, food, fruit, chemical drug intermediates and other materials
.

Problems in the long-term use of Sihuan freeze-drying pharmaceutical freeze dryers are inevitable
.

No matter what things have been used for a long time, there will be some small faults.
Although they will not affect the work for a while, if they are not dealt with in time, the small faults will turn into big problems.
Therefore, learn some simple maintenance methods by yourself.
very important
.

1.
High pressure alarm 1.
There is too much refrigerant in the freeze dryer and the exhaust pressure is high, and part of the refrigerant should be released; 2.
The temperature of the cooling water is high, the flow rate is insufficient or the water condenser is scaled; 3.
There is leakage in the low pressure section of the refrigeration pipeline, Inhale air; 4.
The high-pressure exhaust valve is not fully opened or damaged, resulting in poor exhaust
.

It can be reset through the alarm reset button, and the button switch is on the high pressure pressure relay
.

2.
Water pressure alarm 1.
The cooling water pressure is lower than the pressure set by the water pressure relay
.

It is necessary to ensure that the cooling water pressure is higher than the pressure set by the water pressure relay; the pressure set by the water pressure relay can be appropriately lowered under the condition that the high pressure of the compressor with the cooling effect does not alarm; 2.
The water pressure relay fails
.

The water pressure relay needs to be replaced
.

As long as the water pressure is higher than the pressure set by the water pressure relay, the alarm can be eliminated
.

 　　3.
Oil pressure alarm 1.
The oil return is not smooth, resulting in insufficient oil level in the crankcase of the compressor, and the oil pump cannot absorb oil
.

Generally, a new oil separator needs to be replaced; 2.
The oil is dirty, causing the oil pump filter to be blocked
.

It is necessary to change the oil and clean the oil filter; 3.
The oil pressure differential relay fails
.

Replace the oil differential relay with a new one; 4.
The oil pump fails
.

Replace the oil pump with a new one; 5.
The refrigeration system of the freeze dryer is not well evaporated, and refrigerant enters the crankcase
.

Bringing refrigerated oil into the system, causing the oil pressure to be too low
.

Close the liquid supply valve at the outlet of the condenser or adjust the thermal expansion valve (increase the superheat of the system)
.

After the compressor starts 90s, the oil pressure difference relay will work.
If there is no oil pressure difference, it will alarm.
After the alarm, the reset button on the oil pressure difference relay can be reset to eliminate the alarm
.