Stainless steel vacuum diffusion pump

1. Introduction:

The high vacuum diffusion pump produced by our company is made of stainless steel and air-cooled. It has compact structure and beautiful appearance. The diffusion pump has fast pumping speed and fast reaction. Nowadays, diffusion pump has become an indispensable equipment for obtaining high vacuum in electronic industry, metallurgical industry, atomic energy industry and other industries. In addition to the above industrial departments, colleges and universities, high vacuum laboratories of enterprises and relevant vacuum device manufacturing units all have the use. Its function is to help you get higher vacuum.

2. Technical indicators:

Working temperature: 5 -- 40 ℃

Working humidity: less than 85%

Power supply index: 220 V, 200 W

Fan index: 220 V, 12 W

Upper port diameter: kf50 interface

Lower port diameter: kf16 interface

Pumping rate: 80L / S

Limit pressure: - 4pa of 1x10

Maximum exhaust pressure: 25Pa

Working fluid: 275 silicone oil, 274 or ks-3 diffusion pump oil, with an internal capacity of 25ml

3. Working principle:

The working fluid with low saturated vapor pressure at room temperature is heated by the heater at the bottom of the diffusion pump. The oil vapor generated moves upward along the steam pipe and ejects at high speed through the tower nozzle. A small amount of gas diffused in the oil vapor is carried to the front stage end by the front stage vacuum pump The steam is discharged to the atmosphere; when the oil vapor jet is cooled on the inner wall of the diffusion pump, it flows back to the bottom of the pump, thus repeating the work, thus achieving the goal of high vacuum.

4. Structural features

The diffusion pump is mainly composed of shell, pump core, evaporation pot, heater and cooling fan. The shell of the pump is mainly used to install the pump core to block the atmosphere and condense the oil vapor; the pump core is mainly used to form the flow path of the oil vapor and change the direction of the oil vapor at the same time; the evaporation pan and heater mainly sublimate the oil from the liquid state to the gas state; the cooling fan mainly cools the oil vapor diffused to the inner wall of the pump into the liquid state.

5. Installation operation:

Remove the cover plate of the pump inlet and outlet, observe whether the position of the internal parts is correct, and then install the pump into the required vacuum system, which should be vertical, not slanting or upside down. The upper port is connected with the vacuum system, and the lower port is connected with the front stage pump to ensure the sealing of the upper and lower ports. The pump can work after connecting the 220 V power supply.

6. Operation:

Connect the sensor of vacuum instrument to the vacuum system, start the front stage pump to pre pump the diffusion pump. When the maximum exhaust pressure of diffusion pump is less than 25 PA, generally around 5 Pa, turn on the power switch of diffusion pump for heating, and turn on the cooling fan for cooling at the same time. Generally, the initial heating of diffusion pump starts to work in about 40 minutes, and the limit vacuum is about - 4 PA. When shutting down, the heating power supply of diffusion pump should be turned off first, and then the front stage pump and cooling fan should be turned off after about 15 minutes.

7. Precautions:

1. The heater under the diffusion pump should not be in contact with metal conductors such as the casing to prevent electric shock or electric leakage.

2. In the working process, do not destroy the front stage vacuum and foundation vacuum of diffusion pump to prevent the oxidation of diffusion pump oil.

3. In the process of operation, do not stop the cooling fan for dry burning to prevent the oxidation of diffusion pump oil.

4. The diffusion pump can only remove the harmless gas which has no chemical reaction to the pump and working fluid, such as volatile or high temperature gas, the extracted gas must be cooled in advance.

8. Maintenance:

A. Diffusion pump does not work:

1. Air leakage of the system exceeding the allowable leakage rate: vacuum leak detection to eliminate the leakage.

2. Heater does not work: electric furnace wire is burnt out or circuit fault: replace heater, check circuit, insurance, etc.

3. Insufficient oil heating, low oil temperature: low circuit power, low voltage, and large contact distance between heater and evaporator.

4. The pressure of the front stage is too large, and the vacuum foundation of the system or the front stage pump is poor, which can not meet the normal working pressure.

5. Loose nozzle: tighten it again.

B. Slow pumping speed:

1. The oil temperature is lower than 270 degrees: the circuit power is small, the voltage is too low, and the contact distance between the heater and the evaporation pan is too large.

2. Too little working fluid: add new oil of the same type.

3. Incorrect installation of pump core: disassemble, fix and install.

C. Poor limit vacuum:

1. Vacuum system leak, vacuum leak detection, eliminate leakage.

2. The vacuum system or pump is not clean: clean and vacuum sanitary treatment.

3. Oxidation and cracking of working fluid: replace with new oil.

4. Poor cooling effect: check whether the fan works normally or the ambient temperature is too high.

5. Improper oil quantity: check whether the oil quantity is too much or too little, and adjust it.