Hi,
For this size of a valve I think 6mm CA is a lot. I doubt if the client really mean this type of a requirement as generic for the complete scope of valves.
If really required it is indeed better to consider a SS body if allowed for the pressure rating. I agree with gr2vessels.
What is the...
Hi,
Thanks for your responses.
We asked already for more details and circumstances at which the tests were performed.
At this moment I do have a lot of interest in detailed technical reports of researches done in pre-scribing the selection of the test fluids.
When you specify hydrostatic high...
Hi,
We are facing large seat leakage over metal seated dual plate check valves during commissioning.
Valves are new and certificates show acceptable high pressure seat test hydrostatic (1,1*pd) and low pressure seat test pneumatic at 6 barg.
Valves will be installed in gas application.
At the...
Hi,
Yes the sketch shows the correct type. Note that the PE part must have sufficient length in order to avoid melting of the soft seats/seals and to enable execution of welding.
Normally a minimum length of 75 to 100mm will be applied.
Success.
Hi,
PE stands for Plain End, which means that the end connection is a straight part (e.g. by means of a welded in Nipple or integral machined to forged body) with straight end, so no bevel machined to it.
This type of end connection specified for socket weld piping systems.
FNPT is indeed...
Hi,
Anybody familiar with assessment of hydrostatic test pressures of Piping Systems?
Design code is EN 13480 - 3, so test pressure to be assessed as per EN 13480 - 5. Considering equotion 9.3.2-2 we need to know whether the cold design pressure, or the reduced hot design pressure applies in...
Hi,
Anybody familiar with assessment of hydrostatic test pressures of Piping Systems?
Design code is EN 13480 - 3, so test pressure to be assessed as per EN 13480 - 5. Considering equotion 9.3.2-2 we need to know whether the cold design pressure, or the reduced hot design pressure applies in...
Hi,
The two times the wall thickness is a rule of thumb. It strongly depends on the applicable design code. However, two times the WT sounds fimiliar, but a minimum of 50mm should be considered.
Success, Regards.
Hi,
Thank you all for your input. So far I have concluded that ticku is indeed correct. Hydrotest pressure is 1,5 * design pressure.
The code is now replaced by BS-EN 14161, however, the superseded BS-8010 prt.1 is still valid for our project.
Best regards.
FKE
Hi,
At our office we don't have the design code BS-8010 part 1 (which seems to be superseeded now). However, I'm looking for the formula to assess the hydrostatic test pressure of piping systems.
Anybody who can give me the formula, or refer me to it?
Thanks in advance.
Best regards,
FKE
Hi,
Tables are presented in ASME B16.10. These tables show for each pressure class per diameter the differences between short and long pattern.
All manufactures who supplies according to API 6D have to comply with subject tables.
Success.
Regards,
FKE
Hi,
It's listed in the API 602. Per grade of materials are maximum allowable design pressures presented at different temperature levels.
Class 800 is applicable for Socket weld or Threaded end valves.
Success.
Regards, FKE
Hi,
In that case you can (after wall thickness measurements) use the same formula as presented in the relevant design code.
You can calculate the MAWP of the piping system by filling in the thinnest measured wall thickness.
If the MAWP as a result is higher than the design pressure of the...
Hi,
With respect to welding additional measurements are expected to be taken, and indeed a new WPS/PQR should be prepared.
However, regarding the wall thickness I expect it is not possible. The WPB material is much weaker than the X65. On the welding end or taper zone the WPB material will most...
Hi,
This is depending on the applicable design code for the piping systems, like ASME B31.3. This code gives you the formula and the parameters such as the design stress which you are required to use for wall thickness assessment.
Off course you also need to consider additions such as...
Yes but it must be noted that for wall thickness assessment a weld joint factor must be taken into account for API 5L Pipes.
See table 302.3.4
Regards,
FKE