Without careful selection of the valve and design of the downstream piping you're going to have a problem. Operating a ball valve in the partially open position will direct the flow to either the valve body, the flange, or the downstream piping wall instead of down the bore of the line. This...
Yes, the pump will cavitate if you don't have enough NPSH. Depending on the pump the friction losses in the suction piping can be enough for the suction head to fall below NPSHr.
Also note that there can be other, non-code requirements for PWHT. One such example is concerns around mitigating stress corrosion cracking in sour service.
If this is an ASME B31.3 system the spool would need to be re-hydro'd unless:
You use a closure weld (and the jurisdiction allows it)
It is new construction and you follow the requirements of B31.3 para 345.2.6 (i.e. owner waives the requirement and appropriate precautions are taken
Hello,
I'm troubleshooting a pump system and am hoping the community here can provide some insight into what kind of issue I might be dealing with.
First some background:
System consists of two parallel centrifugal pumps feeding two parallel recip pumps
Centrifugal pumps are on VFDs but have...
Hello,
I have been asked to look into whether or not it is possible to redesign/re-certify existing storage tanks that were designed and constructed to API 12F to be compliant with API 650.
My initial feeling is that this will not be possible due to the more stringent examination requirements...
Thank you for the reply Mike. Now that you have mentioned that paragraph I feel quite silly for missing it.
I am accounting for ribs as per TEMA RGP-RCB-11.7 Pass partition rib area.
I will also look at applying PCC-2 Appendix O to this issue and see what I can come up with.
Regards,
Dan
Hello,
I am trying to determine the bolt loading requirements for the channel head to vessel shell connection on one of our heat exchangers. There is a fixed tubesheet between the two flanges.
Searching for an approach to calculate the bolt loading requirements for this type or arrangement...
I got it all sorted out, I had missed the part about the patch for nozzles under a certain size not needing to be any larger than twice the diameter of the nozzle.
We had the weld between the nozzle and the shell crack. The crack really turned into a hole as it was more than 1/4" wide in some...
I've got a question along these same lines. I had a weld on a nozzle fail and am looking to repair it according to article 2.1 however there is another nozzle 6" away from the first. I am worried that installing a patch so close to the other nozzle weld will lead to another failure.
A little...