Pipeline installation of laboratory high purity gas control system

Wiring of air circuit

1. SS 316L BA pipe is used to connect the pressure regulating panel in the cylinder room with the gas terminal in the laboratory. The inner surface finish of the pipe is Ra<0.4um BA pipe.

2. The 4N nitrogen main line adopts OD3/8 "(6.35mm) pipe, and the flow rate can reach 8M3/ hour under 0.5mpa pressure, which fully meets the demand of conventional gas. The branch line adopts OD1/4" (6.35mm) pipe. The gas supply to the equipment is provided by a branch of welded tee.

3. 5N Main line of nitrogen, helium and reserved gas shall be od1/4 "(6.35mm) pipe, and branch line shall be OD1/4" (6.35mm) pipe. The gas supply to the equipment is provided by a branch of welded tee. 16. Pipe sleeves shall be used when the pipe passes through obstacles and the gap shall be filled with non-combustible materials.

4. The most advanced American automatic positioning rail type TIG welding machine is used for internal and external protective TIG welding between pipes. Its advantage is that the leakage rate can reach 1x10-9S.C.C. /sec.He, and there will be no oxidation layer or wrinkle on the inner surface of welding defects.

5. All the tees on the pipeline are welded to connect, which can guarantee the transmission quality of gas more effectively.

6. The pipe shall be fixed on the pipe bracket with fixed clamps. Pipe support for channel steel structure beautiful and generous. Fixed firmly with walls and pipes. And made of refractory material (aluminum alloy).

7. The gas pipelines should be horizontal, flat and vertical during the laying process. To ensure the straightness of pipeline routing and the distance between pipes, a set of pipe cards should be set at a certain distance. Fixture should be made of non-combustible material, beautiful and generous.

8. Bend should be reduced as far as possible to prevent the transmission of gas pressure, flow loss is too large. The pressure pipeline should be strengthened in the area where the bending stress is concentrated, and the appropriate turning radius should be designed. The bending part should not be wrinkled and twisted. Bending radius and bending quality are guaranteed by special tools. System wiring should minimize joints to reduce the possibility of leakage.

9. When piping, each pipe and each pipe fitting shall be purged with 5N high-purity nitrogen at high pressure before it can be connected to the system. After the installation of the whole system, 5N high-purity nitrogen shall be used for high-flow gas purging to ensure the cleanliness of the system, that is, no grease and obvious solid particles will flow out of the gas.

10. After the installation of the system, high purity nitrogen should be used to test the air tightness of the high pressure part and the low pressure part to test the whole system.

11. Labels such as gas path number, gas type and concentration are pasted on the pressure adjustment panel and gas path control terminal.