Application of stainless steel pipe in high purity gases pipeline transportation system

- Mar 28, 2019-

High-purity stainless steel pipes are used in many applications: high-purity and ultra-high-purity gases, flammable and explosive gases, toxic gases and other special gas piping systems, secondary piping, and other gas equipment.

In the process of stainless steel smelting, about 200g of gas can be absorbed per ton. After the stainless steel material is processed, not only the surface is contaminated with various pollutants, but also a certain amount of gas is absorbed in the metal lattice. When there is airflow in the pipeline, this part of the gas occluded by the metal will re-enter the gas stream and pollute the pure gas. When the gas flow in the tube is discontinuous, the tube adsorbs under the pressure of the gas passing through, and when the gas flow stops, the gas adsorbed by the tube forms a pressure drop analysis, and the analyzed gas also enters the pure gas in the tube as an impurity. At the same time, the adsorption and analysis are repeated, so that the metal on the inner surface of the pipe will also produce a certain amount of powder. This metal dust particle also pollutes the pure gas in the pipe. This property of the pipe is of utmost importance. In order to ensure the purity of the gas to be conveyed, it is required not only that the inner surface of the pipe has an extremely high smoothness, but also that it should have high wear resistance.

The high-purity gases piping technology is an important part of the high-purity gas supply system. It is the key technology that can pass the required high-purity gases to the gas point and still maintain the quality. The so-called high-purity gases piping technology includes the system. Correct design, selection of pipe fittings and accessories, construction and installation, and test and test. In particular, some of these gases, such as the self-ignitability of SiH4, will react violently with the oxygen in the air as soon as they leak, and begin to burn. There is also the toxicity of AsH3. Any slight leakage may cause harm to human life, that is, Because of these obvious dangers, the requirements for system design safety are particularly high.

Corrosion-resistant stainless steel pipe should be used as the pipe with strong corrosion resistance. Otherwise, the pipe will have corrosion spots on the inner surface due to corrosion. In severe cases, large pieces of metal will peel off or even perforate, thus contaminating the pure gas of the distribution. .

The connection of high-purity, high-purity gases distribution pipelines in large flow is in principle all welded, and the required pipes are not changed during the welding. When the material containing too much carbon is welded, it is permeable to the welded part, so that the gas inside and outside the pipe penetrates each other, destroying the purity, dryness and cleanliness of the conveying gas, and all our efforts are