need to specify valves for up to 1500 psi 2

[vodeni]

Hi all,
Most of my life I dealt with municipal side with pressures up 50 200-300 psi, now I have a task to specify valves for the pump/piping system (water) for the pressures in excess of 1,300 psi. Can you please point me to right direction rgarding the following issues:

1.Isolation valves (gate valves) Manufacturer, specifications, tye of construction, and also at that pressure and flow of up to 700 gpm do we need an electric or hydraulic actuator or the operator could still be able to operate with the handwheel.
2. Check valve (I assume gate valves and check valves should be class #600). We have VFD on the pumps so I think a simple swing check should work. Any suggestions?
3. Air/Relief and combination Air Vaccum valves for the pipeline. Manufacture? Type?
4. Pressure relief valve to provide relief in case of overpressuring the line due to power outage, or similar.

Thank you for your input

 

[bcd]

Class 600 gate valves...there are more manufacturers than you can point a stick at. Especially from China. Might be good to start at

http://www.vma.org.

The Valve Manufacturers Association publishes a "Buyers Guide" which lists the various valve types and who makes them. I recall being able to see it online from their website. If a company is in the Buyers Guide, they are in North America and have been around for awhile, so they can be trusted to make a good product.

 

[vodeni]

Thanks,
I got that covered with gate valve, I am working with Crane, Velan, etc.. but want your input regarding an actuator. I am not quite sure about actuators though. Not getting straight answer from the reps on the torque and what would it take to manually operate at 1,500 psi 700 gpm.

 

[vpl]

For nuclear service, Limitorque is the standard actuator manufacturer.

Patricia Lougheed

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[BigInch]

The size of valve, how many times its required to be operated, the ease of reaching its location and its required opening/closing time will have more to do with specifying an actuator than the actual pressure rating, although that does increase opening and closing torque. Generally you might want to spec actuators at 8" or 10" size and above, but its not unheard of to have motorized 4", nor a manually operated 24". Assuming you have somewhere around a 6" pipeline, I'd base it on the number of ops per day and travel speed requirements rather than it being too difficult to open or close by hand.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
"Being GREEN isn't easy." Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.liv

 

[racookpe1978]

Continuing that line of thought: Rather than torque and time, have you considered the "why" the valve the needs to be closed (emergency conditions? Simple shutdown, rarely done? To fill the tank or pressure vessel routinely? To blow down the pipe every 24 hours? From the plant floor with a nearby employee always there? Or remotely (at the top of the tank or on the fourth floor requiring a 15 minute trip up the ladder to get to the valve?

The "operate the valve from where" is important: Can you stand on the floor and get to it? Get a truck and have to drive to the end of the property and climb a pipe stand? Use a chain and rack to operate a valve up high - but not need an electric actuator at all? Have the machine operator reach over and turn it?

Valve actuators are expensive (add in controller, actuator itself, feedback trips and wires, the remote switching station and the indicators, the control room wiring and lights. It adds up to more than just the mechanism.)

But - what is the cost if the valve can't get operated quickly? What is the risk of leaving it open for 10 minutes until you can get somebody to go close it? How much are you paying your 3-shift operators plus a spare?