Discuss again whether a short circuit needs to be added between the two valves in series
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This post was last edited by *aoguai607 on 2010-5-27 at 10:34. Someone else discussed this issue before, and I still can’t figure out why a short circuit is needed. Many people say it’s difficult to maintain and assemble/disassemble. I ask, since it’s also a flange connection, why could it be more difficult than when a short circuit is used? If no short circuit is installed, a lot of work can be saved. The previous post is at: http://bbs.hcbbs.com/thread-512517-1-1.html. I ask the experts to discuss it again.
In my opinion, flange connections are used in most cases; since bolts cannot pass through between the flanges of two valves, a short pipe needs to be added.
The double-headed bolts used nowadays make connection very easy. It’s rare for the bolts used to secure the valve flanges not to be able to pass through; this can be considered a special case. But many people say that installation and maintenance are difficult. I don’t understand this – for two valves connected directly without any splices, 3 sets of bolts are sufficient. If splices are used, then there are two additional welds and more bolts required. Is it perhaps a matter of finding pleasure in work, where doing less work seems difficult?
I agree with what was said on the 2nd floor. Today, double-ended studs are used. In some cases, the distance between the valve flange and the valve body is quite small; if two valves are connected in series, it may not be possible to insert the bolts. From a process perspective, connecting the two valves in series should be no problem. But I don’t understand why two valves need to be connected in series?
For valves with two concave sealing surfaces, it is difficult to ensure proper installation quality without using a bypass; moreover, without a bypass, the two handles tend to interfere with each other, making it inconvenient to operate the valve.
The last edit to this post was made by Lao Baoli on 2010-5-28 at 11:18. It’s fine to connect the two valves in series in the process flow; as long as the piping is properly arranged for easy operation, the sealing surfaces match, and there are no issues such as bolts not being able to pass through or the valve stems interfering with each other, as mentioned by others, then the two valves can indeed be connected in series