Installation and preparation of lyophilizer:

1. The vacuum pump and the main engine are connected by a vacuum pressure pipe, and the two ends are equipped with a standard quick clamp. The clamp is equipped with a rubber sealing ring. Before connecting, apply a proper amount of vacuum grease on the sealing ring, and then clamp the clamps at both ends.

2. A "general power" socket is installed above the right board of the host, and one end of the power cord is inserted into it, and the other end is connected with the power supply. The power socket of vacuum pump is installed on the side of "main power", and the power line of vacuum pump can be plugged in.

3. Please read the "operation manual" of vacuum pump in detail, check the vacuum pump, confirm that the vacuum pump oil has been filled, do not run without oil, and the oil level shall not be lower than the center line of oil mirror.

4. The "O" type sealing ring above the cold trap should be kept clean, and a layer of vacuum grease can be evenly coated before use.

5. Put the material into the material tray, then put the material tray on the pre freezing frame, put the pre freezing frame into the cold trap, cover the insulation cover, and pre freeze for ~ hours.

6. If the capping configuration is selected, the material is injected into the vial, and then the vial is put into the cold trap for ~ hours. After the pre freezing, the vial is put into the material tray covered for drying.

7. If the multi manifold configuration is selected, the material is injected into the selected drying bottle, and then the drying bottle is put into the cold trap, and the heat preservation cover is covered, and the pre freezing time is ~ hours. If possible, the drying bottle can be rotated and pre frozen, so that the materials can be evenly frozen on the bottle wall, which is conducive to accelerating the drying.

8. Press and hold the "total power" key on the control panel for three seconds, and the control system is powered on. At this time, the temperature window displays the temperature of the cold well coil at that time. Please check the possible leakage points, valves and relevant sealing rings one by one with exclusion method.

Freeze drying machine is widely used in pharmaceutical production. However, due to the continuous process of freeze-drying, once the freeze-drying machine fails, it will seriously affect the production and bring losses to enterprises. Experts from Beijing Songyuan Huaxing Technology Development Co., Ltd. sorted out the daily maintenance and common problems of the important refrigeration system, hoping to help the lyophilizer users

1. Daily maintenance of refrigeration system

(1) Routine inspection shall be carried out before each startup:

1) Whether all stop valves (suction and discharge valves, liquid supply valves, hand valves, etc.) of the compressor are in the open state;

2) Whether the reading of each pressure gauge is normal (0.6 ~ 0.7 MPa);

3) Whether the compressor oil level is normal (1 / 4 ~ 3 / 4); 4) whether the cooling water pressure (above 0.1 MPa) and temperature are normal.

(2) After power transmission, attention should be paid to:

1) Whether the compressor receives liquid automatically;

2) Whether the oil pressure difference is reset, etc;

3) Check the heating condition of the heater of the crankcase. The temperature of the crankcase should be 20 ℃ higher than the ambient temperature.

(3) Pay attention to the following after starting the machine:

1) Whether the running sound of compressor is normal;

2) Whether the refrigeration pipeline has abnormal vibration;

3) Whether the vibration of compressor itself is minimum;

4) Whether the flow rate of the lens is normal;

5) Frosting of expansion valve;

6) Compressor defrosting.

(4) The compressor refrigeration oil shall be changed every half a year or once a year as the case may be.

(5) Water cooled condenser needs to be cleaned regularly, usually for 1 year. It can be disassembled and washed, and can also be used for circulating cleaning with water treatment cleaning agent. For air-cooled units, clean the outer surface of condenser in time.

(6) Note that the compressor can not be started frequently, and the starting interval should be more than 3 min.

2. Common problems and Solutions

2.1 if the high pressure is too high, the high pressure alarm will occur

(1) There are too many refrigerants and the exhaust pressure is high. Some refrigerant should be discharged.

(2) Insufficient cooling water temperature of condenser.

(3) There is leakage in the low pressure section of refrigeration pipeline, and air is inhaled.

(4) High pressure exhaust valve is not fully opened or damaged, resulting in poor exhaust.

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

2.2 oil pressure differential 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, it is necessary to replace the oil separator.

(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) Oil pressure differential relay failed. Replace the oil pressure differential relay with a new one.

(4) The oil pump is out of order. Replace the oil pump with a new one.

(5) Refrigeration system evaporation is not good, there is refrigerant into the crankcase. The refrigerant oil is brought into the system, resulting in low oil pressure. Turn down the liquid supply valve at the outlet of the condenser or adjust the thermal expansion valve (increase the superheat of the system).

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

2.3 thermal protection of compressor (motor temperature exceeds 85 ℃)

The air return of the system is insufficient and the motor is not cooled sufficiently.

terms of settlement:

(1) Adjust the intercooler expansion valve to increase the circulation of the system, so that the motor is fully cooled.

(2) Check whether the liquid supply pipeline is blocked (liquid supply stop valve, drying filter, solenoid valve, filter screen in front of expansion valve, etc.), and solve the problem if any.

(3) Check whether there is blockage in the air return pipe of the compressor and the filter.

(4) Check whether there is a lack of refrigerant, if not, replenish it. When the 220 V control power supply of thermal protection is turned off and restarted, the alarm can be eliminated.