Knowing the design of the laboratory knows that any design of the laboratory has specifications. If the scope of this requirement is exceeded, the design of the laboratory will have loopholes. If it is unqualified, it will be prone to accidents. The discharge of gas in the laboratory is very important. If the design of the laboratory gas pipeline is unreasonable, the staff will be prone to accidents, and even serious will be life-threatening. Then what are the requirements for the design of the laboratory gas pipeline, there is a small series and everyone to talk about it!
1. Calculate the gas supply pressure, the flow and the inner diameter of the pipe according to the gas consumption of the laboratory. In principle, all gas main pipes are not less than 9.52mm (3 / 8in, the instrument air main pipe diameter is 12. 7mm). The end. In principle, it is not less than 6.35mm (1 / 4in, depending on the actual usage).
2. Hydrogen, oxygen and gas pipelines as well as various gas pipeline branches leading to the laboratory should be applied. When hydrogen, oxygen and gas pipelines are laid in the pipeline well and pipeline technical layer, ventilation measures should be given for ventilation once/h~3 times/h.
3. Flammable gas (such as acetylene, hydrogen, etc.) needs to be separated from other gases and attracted separately.
4. The general laboratory designed according to the standard unit combination, the various gas pipelines should also be designed according to the standard unit combination.
5. Gas pipes that pass through the laboratory wall or floor should be placed in the pre-embedded casing, and the pipes in the casing should be free of welds. Non-combustible materials should be tightly sealed between the pipeline and the casing.
6. A venting tube should be provided at the end and the highest point of the hydrogen and oxygen piping. The venting pipe shall be above the roof Zm and shall be located in the lightning protection zone. The hydrogen pipe shall also be provided with a sampling port and a purge port. The position of the venting tube, sampling port and purge port should be sufficient to meet the requirements of gas purge replacement in the pipeline.
7. Hydrogen and oxygen pipelines should have grounding measures to remove static electricity. Grounding and bridging measures for gas pipelines with grounding requirements shall be carried out in accordance with the relevant national regulations.
8. Pipe laying requirements:
a) The pipeline for conveying dry gas should be installed horizontally, and the pipeline for transporting humid gas should have a slope of not less than 0.3%, and the slope should be condensed to the liquid collector.
b) The oxygen pipeline and other gas pipelines may be laid on the same shelf, and the spacing shall not be less than 0.25 m. The oxygen pipeline shall be above the other gas pipelines except the hydrogen pipeline.
c) When the hydrogen pipeline is laid in parallel with other combustible gas pipelines, the spacing shall not be less than. 50m; when cross-laying, the spacing should not be less than 0.25m; when laying in layers, the hydrogen pipeline should be above. Indoor hydrogen pipelines should not be laid in the trench or buried directly, and should not pass through rooms that do not use hydrogen.
d) The gas pipeline shall not be laid on the same frame as the cable or the point line.
9. Pipes and equipment should be connected with metal pipes. For non-metallic hoses, it is advisable to use polytetraethylene pipes and polyethylene pipes. Latex pipes should not be used.
10. Material of valves and accessories: Steel materials should not be used for hydrogen and gas pipelines, and other gas pipelines can be made of copper, carbon steel and malleable cast iron. The accessories and instruments used in the hydrogen and oxygen pipelines must be special products for the medium and must not be substituted.
11. Non-combustible materials should be used in the valve contact with oxygen. The sealing ring should be made of non-ferrous metals, stainless steel and PTFE. The filler should be degreased graphite asbestos or polytetrafluoroethylene.
12. Flange gaskets in gas pipes shall be made of the medium to be transported in the pipe.
13. The connection of the gas pipeline should be in the form of welding or flange connection. The hydrogen pipeline should not be connected by screws. The high purity gas pipeline should be socket welded.
14. The connection of gas pipelines to equipment, valves and other accessories shall be flanged or threaded. The threaded joints of threaded joints shall be made of Teflon film or lead oxide or glycerin blending filler.