Single acting piston and pressure reducing valves

[santosjerome]

I am looking for a single acting cylinder that can work both nitrogen and water as a service fluid and range of pressure between 0 and 22500psi.
Also I am looking for a pressure reducing valve that can work both nitrogen and water as a service fluid. Maximun pressure inlet 22510 psi
Anyone can help me it companies that fabricate or develop this kind of equipment.
Thank you

 

[LittleInch]

i think the lack of response might tell you something. Those figures look very high, but without some idea of flow rate or why the range is so high it is difficult to offer anyhting more. having either a liquid or gas in the same thing is very difficult.

Even in terms of oil wells I've not seen >20,000psig before and even 10,000 psi chokes are very well built things that cost a small fortune. Depending on your flow rate ook up Cameron or valtec, or search wellhead choke valves.

Can you describe what it is you're trying to do and why you can't do this with a staged pressure or pressure reduction set-up as this is so far out of the nomral range that yu will need somehting very special that costs a very special amount of money....

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[santosjerome]

Hi Litleinch
Thank for your comment. I will try to explain what I am trying to do.
I am trying to implement a safety device in a Test Connector. The Test Connector is a Tool used as a pressure barrier to perform Hydrostatic and Gas Tests on Subsea Christmas Trees. This test connector as two chambers, Unlock and Lock operated by hydraulic oil up to 345 Bar.
Safety issue
Possible to apply pressure to Unlock Chamber during testing of XMT/Spool. This could result in a major accident. Implementing a Safety System will guaranty that no pressure will be applied to Unlock Line while test is being performed on XMT
Safety System
When we are ready to test the XMT the connector is in locked position, what i want is to use the pressure that the Subsea christmas will be submited to colse the unlock line on test connector.
A Cylinder Single Acting that hold pressures achieved by Gas and Water from 0 to 22500 PSI.
A Pressure Reducing Valve installed before the Cylinder will allow us to have a minor working pressure range in the Cylinder.
This cylinder will be connected to a normally open Valve that will close when pressure on cylinder is detected.
Equipment:
- Pressure Reducing Valve
- Single Acting Cylinder
- Normally Open Valve
- Autoclave Tubing needed 3/16”
It is desirable that the Normally Open Valve close/open when pressure in the Bore line is above/below 0 to 1 BAR.
All equipment should be projected to work both gas and water.
Test pressure is 1552 BAR/22510PSI, equipment should be projected/tested to work above test pressure.
The range of working of the Single Acting Cylinder depends of the Pressure Reducing Valve.
It has to be a mechanical system since during gas test all Christmas tree and test connector will be under water.

 

[LittleInch]

Can you sketch this please, I just can't follow it properly.

Not sure why you can't work with a locked closed valve on the unlock line? There are some mechanical key systems available which can help to avoid accidental opening but working with these these sorts of pressures is not easy and could cause more risk than what you are tyring to do, but please draw a schematic so we can see exactly what you're trying to do.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[santosjerome]

Normal operation of the Test Connector for gas or hydrostatic test.
1.
Make sure that Test Connector is in Unlock position.
2.
Land the Test Connector on XT.
3.
Vent Connector Unlock and apply 345 BAR/5004 PSI on Connector Lock.
4.
Make the necessaries preparations to connect Water hoses to the XT.
5.
Apply Water through Subsea XT until the Test pressure 1552 BAR/22510PSI. Holding period 15 min and droop of pressure within criteria.
6.
Remove all Water from the XT and blow with air the XT to remove possible remains of water.
7.
Make the necessaries preparations to connect Gas hoses to the XT.
8.
Fill the pit with water until all XT and Test Connector is under water. (All lines where gas is should be under water to identify possible bubbles)
9.
Apply Gas through Subsea XT until the Test pressure 1552 BAR/22510PSI. Holding period 1 hour and droop of pressure within criteria. Leakages will be detected if any bubble appear. All system could be under water for many hours and in some cases days until criteria is achieved.
10.
When test is completed. Blow out the Nitrogen to the water in the pit.
11.
Remove the water from the pit.
12.
Make sure no pressure is in the XT. Vent Connector Lock and apply 345 BAR/5004 PSI on Connector Unlock.
13.
Remove the Test Connector

 

[LittleInch]

I can see what you're trying to do, but realistically doing it in a mechanical way I don't think will work and simply leads to other potential high pressure hazards. Either do this action (shutting the valve) by procedure and / or mechanical key lock system or include a presusre switch (which exist for this pressure without a problem) and set at some low pressure and use that to actuate the valve closed or it actuates a solenoid which stops the valve being opened. you could do this fail safe, i.e. the solenoid / valve only opens on low pressure and closes by a spring on high pressure.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way