Rising or non rising stem gate valve 1

[sowhatso]

All ,

For buried application , what is the recommended type of gate valves to be used , rising or non rising stem gate valves , an why ?

 

[BarryEng]

For buried applications, use non rising spindles. Most retic (water utilities) use buried valves &, obviously, do not want spindles to rise, especially in applications where they want the valve to be permantly closed (for example) at the boundaries of high level areas, or in areas that they require to have a valve permantly open.

In the old days, there used to be two types of valve standards - sluice valves & gate valves.

Sluice valves were very robust & were suitable for buried applications (left buried for up to 50 years - water utility). They were fabricated in a very thick walled type of valve for corrosion requirements (over 50 year life).

Gate valves (originally) were thinner walled & were designed for locations where they could be inspected daily. This was in most treatment plants or process plants. This meant they were located above ground in a situation where they could be visually inspected every time someone walked past.

Remember, most water utilities have people working on their valves who are basically labourers (hence the more robust sluice valves). Most process plants have people who work on valves, are usually fitters & turners (hence gate valves that are thinner & have rising spindles). A rising spindle (in a process plant) is a very simple (visual) indication of the position of the valve.

Remember that a buried service condition is a very different situation to a valve that is located in a process plant & subject to a daily inspection.

 

[rconner]

I think you have gotten a good response from BarreyEng. Incidentally, I think this basic type subject has been discussed many times on these lists, with more information available with "Advanced Search" in the archives (e.g. see

http://eng-tips.com/viewthread.cfm?qid=180427

and

http://www.eng-tips.com/viewthread.cfm?qid=180412&page=1

etc.)

 

[Sid7]

rconner

Thanks for your post. The second link is broken in both the posts. Ant idea whats wrong?
regards,

Siddharth
These are my personal views/opinions and not of my employer's.

 

[rconner]

Not sure, but you could see many posts e.g. by going to "Advanced Search" yourself and then say entering keywords "rising stem" (I looked at "OS&Y Gate Valve" post I rremembered)

 

[sowhatso]

Thanks alot for all your input , I looked through VELAN Valves catalouge and I was interested to find Class 300 gate valves for buried application , Does anyone know if VELAN produce Class 300 gate valve with NON-RISING STEM ? I tried to contact the sales department but I'm didnt get any answer .