Do the pipes on both sides of the pipe gallery truss and the top pipes need to be vented and purged with valves?

The position of venting and draining needs to be set at the low point and the venting at the high point. It has nothing to do with whether it is a truss or not. It is just that the probability of a high point appearing in a truss is greater, which creates an illusion for you.

I agree with the second floor, it has nothing to do with where the pipe is placed, but it has to do with whether the pipe has high points where gas is retained and low points where liquid is retained.

This is the reason for the director, but some bags are very small and require many items to be added, and some are not included in all, which is confusing.

Except for media with special requirements, it should be added. The purpose is that after the pipeline is installed, most pipelines need to undergo a hydraulic test. At high points, the gas in the pipeline needs to be discharged cleanly. Without venting, the requirements cannot be met.； After the hydraulic pressure test is completed and before starting the operation, the water in the pipeline needs to be drained cleanly, so low-point condensation needs to be drained. If there is no valve at the low point, then there will be water in the U-shaped bend, and some of it can indeed be purged with compressed air or nitrogen. However, this should be considered during the design, otherwise there will be many difficulties in the operation phase. As a designer, the pipeline direction should be considered during the plane planning stage to minimize the occurrence of U-shaped low points. Then there will not be many pockets during the piping process, reducing the number of low-point condensate drain valves. ； When you do design, you just draw a valve. In the factory workshop, people need to open and close the valve. If you think about it from another perspective, you won’t find it troublesome.

But to be honest, adding these discharge valves has added a lot of leakage points to the actual operation, and there are unsafe factors. Especially in the third-party liquid chemical warehousing industry, materials need to be replaced frequently, and these discharge outlet pipes are not clean.

So I’m quite confused. At present, I’ll add the large pipeline first, and then decide whether to add the small pipeline according to the medium.

General low point regulations: 1. There are no high or low points for emptying flammable gas, acidic water, acidic gas, hydrogen, fuel gas, condensate, liquefied gas, amine liquid, and toxic and corrosive fluids. 2. Only set low points for oily sewage, heavy dirty oil, light dirty oil, gasoline, diesel, heavy oil, etc. and use flange covers. 3. Valves and flange covers are installed at the high and low points of hot water condensation water. 4. Other public system pipelines (pa, ia, n2, etc.) are equipped with valves and flange covers at low points, but not at high points.