I am seeking any help regarding the rationale behind the limitation on actual yield strength to 20000 psi as specified by supplementary requirement SR 5 of MSS-SP-75, spec. for butt welded steel fittings.
This requirement is not reflected in ASME B16.9.
I have been told it is to ensure better...
both MSS-sp-44 and B16.5 state:
"Rat ings for welding neck flanges covered by this
Standard are based upon their hubs at the welding end
having thickness at least equal to that calculated for pipe
having 276 MPa (40,000 psi) specified minimum yield
strength.1"
It is not clear which piping code...
Hi All,
Is it correct to to assume that a slip on flange designed to appendix 2 (say 275 psig design pressure) is also by default capable to withstand the full hydrotest pressure of 1.5 times the DP as allowed for say a B16.5 flange ?
Per my understanding,the code does not directly address...
I was recently made aware that the B31.4 code states (400.1.2) that it was not developed for piping with design temp. less than -30 dgrees C. My query is what code do we follow for cases where we have lower temps e.g. -34 C as is the case for some areas of NE USA.
The Canadian pipeline code...
Hi,
I would like the opinion of experts here on an issue related to post bend HT for induction bends to ASME B16.49.
A vendor is claiming that post bend heat treatment is not required for certain bends which have been ordered on them & per SR15.1, it does appear to be the case. some of my...
I have a problem regarding induction bends.
A contractor ordered and installed 20" induction bends without going through the the process of making and testing the qualification bends as required per B16.49 and our specs.
The actual bends were put into service without any NDE and the final...
Hi All,
I want to know if Version 6.0 of CII does a check for the combined equivalant stress when performing underground piping analysis to check for stresses as per API 1102 ?
I understood this was in the works some years ago but I do not know if this has been incorporated in the software ...
I want to know whether the compression type type of fittings and joints used by Swagelok / Parker are actually allwed by code (B31.3 /B31.4 ?
If yes under which clause ?
Hi,
I have a consultant who advises against using EHT (electric heat tracing) on galvanised pipe for firewater purposes on the ground that the localised heating can deteriorate the internal coating, cause clogging & premature corrosion failure of the pipe.
I am unconvinced that the problem is...
Hi,
I want to know the impact of welding different grades of carbon steel e.g. API 5L X52 to X65 or X42 to X52.
For strength purpsoes I understand the common practice is to consider the weaker steel for the complete assembly, but my question is more from the metallurgical and weldability point...
Hi.
I want to know if anyone has done a modal analysis of small bore bramch connections (<=2") on larger pipe(> 20") in CII ?
Are the results comaprable to say a FEA analysis ?
And can one run a fatigue analysis on such a cnnection due to say a harmonic forcing function i.e. vibration of the...
Hi,
I want to know if the B31 codes specify unique requirements for reinforcement of branch connections on elbows and bends or are they to be treated as for straight pipe ?
Similarly are the branch SIF's to be treated differently ?
I have read about some issues on the subject but would like to gain more information.
By how much would the pressure pulses generated by vane pass of centrifugal pumps be dampened out as the fluid flows down the line ?
Is there any method to estimate or an empirical corelation ?
We normally...
Hi,
An issue I have is the restrictions that the pipeline codes impose on structural attachments and the need to have full encircelement sleeves. For example B31.4 states:
404.9.1
..... If the pipe is designd to operate above 20% SMYS all attachment welded to the pipe shall be made to a...
Accordiong to the B16.5, flanges are not required to be hydrotested as part of the manufacturing process. However flanged fittings are not exempt. Is there a specific reason ?
Hi,
I have been trying to find guidelines on how to evaluate reaction forces for DANFLO type pressure safety valves which release the fluid in the same linear direction downstream upon activation.
I tried to contact the supplier but of no avail.
Appreciate any feedback here.
I would like to receive feedback about the benefits of including friction of supports in dynamic analysis - from analysts experienced in this.
A view I have heard is that including a factor for damping is sufficient and hence you do not need to include for friction while doing dynamic analysis...
