Can plastic pipes be used for automatic instrument air lines?

Where is the factory located, and what are the environmental conditions like? For harsh on-site environments, it’s better not to consider plastic pipes.

As long as the environmental conditions permit, it is sufficient to meet the air demand for instruments.

It can be used, but it will age, the pipes may crack, and the connections may leak air. Therefore, it is best to use stainless steel pipes or copper pipes.

The last edit to this post was made by ZhiGE on 2019-8-26 at 14:41. Chemical companies: Generally, the gas supply pipelines that lead to valves are made of SS316 tubes rather than plastic tubes, and this is due to requirements related to safety and reliability; the cost savings from using plastic tubes do not outweigh the expenses associated with shutdowns caused by failures in the gas supply pipes； 2. Fire protection requirements for valves: Select a sun-resistant, easily fusible material (such as polyethylene pipes) for the section of the gas supply pipeline located near the valve ； 3. In situations where strict requirements are not imposed on safety and continuous production, and where gas supply is centralized indoors and there may be relative movement, such as in quantitative packaging systems, plastic pipes can be used (with regular inspections) ； 4. In applications where there is relative displacement between the pipeline and equipment in which the valve is located and the gas supply pipeline, and where high safety and reliability standards are required, plastic hoses with an SS woven layer can be used.

Hello, which one of API 6FA and 607 mentions this? ? ?

Using plastic of better quality is acceptable

It can be used inside the box. It is recommended to use metal pipes outside the box.