Problem with exhaust at the high point of gas pipelines?

What is the purpose of installing an exhaust port on a gas pipe? How much pressure? If there are no valves, aren’t you worried that the pipe caps might be blown off?

This post was last edited by ylb913 on 2015-7-8 09:09. It is a statement from some standard: for high-point exhaust systems, no valves are required; instead, pipe caps or flange covers are used. Such systems can only be applied to non-hazardous media, and it must be possible to stop the flow of material immediately when liquid is detected at the high point, and to resume the flow of material after the system is sealed again. ”This isn’t very realistic. Very few pipelines are equipped with vents at high points. In our system, such vents are only present in the inlet systems of certain pumps; after the material comes out of the bottom of the tower, it passes through multiple sets of heat exchangers. There are no buffer tanks, and after heat exchange, the fluid goes directly into the pump inlet. In these pipelines, fluid flows from top to bottom inside the heat exchangers. As a result, at the beginning of operation, a large amount of gas remains inside the heat exchangers, and without venting this gas from high points, the pumps cannot operate continuously. We have two more pumps; one is directed at the bottom of the tower, and the other is directed at the acidic water tank. Both inlet pipelines have inverted \"U\"-shaped high points, and there is no venting at these high points. After starting the pumps, it is necessary to monitor the situation for half an hour; by maintaining a slight vacuum, the gases will be gradually removed.

I thought it was for pipeline pressure testing and airtightness testing

Except as otherwise specified for the high-point venting process, it is generally required for hydrostatic testing. Because during pipe flushing, the gas accumulated in the higher areas must be expelled before water can fill the pipes.

In terms of design, there should be exhaust at the higher points and drainage at the lower points; don’t worry too much about these minor issues!

I’m not quite sure about this; check the original poster’s explanation. I’ve never encountered such a problem

I mainly don’t understand the statement that for pipes within the device, other than those on the pipe tray, those with a DN of less than or equal to DN25 do not require a high-point vent – does that mean that air accumulation doesn’t occur in small pipes?

It means that no setup is needed for the pipeline; there’s not much difference between having it and not having it, but it doesn’t say that it’s not required elsewhere

It’s just relative to smaller pipes..

The problem itself is the issue: should no valve be used, and instead a threaded pipe cap or flange cover be used for sealing? What is this supposed to do?