Recent content by yukon09

Cost is not an issue and do right thing to avoid Loss of Containment is the most important. A single leaking will cost money to fabricate thousands of spools and also an environmental disaster.

Hi, Metengr, great point regarding code language and engineering judgement. It is always good to have questioning attitude about the codes and standards.

There is another issue regarding the branch connection weld. some engineers consider the groove weld of branch to run pipe as pressure containment weld, and the groove weld+ fillet weld of repad to branch is non-pressure containment weld/ attachment weld/ Weld reinforcement. IS this reason for...

Hi, DekDee, and Metengr, I appreciate your great insight on this PWHT issue. I have compared B31.3 and B31.4 and found the discrepancies between the codes. From B31.3, as mentioned by Dekdee, PWHT requirements are based on "control thickness". For the branch connection with repad, the control...

I have questions regarding PWHT on ASME B31.4 piping welding "434.8.9 Stress Relieving (a) Welds shall be stress relieved when the effective weld throat (see Fig. 434.8.6-2) exceeds 1 1/4 in. (32 mm)..." But there is another clause: "The thickness to be used to determine the stress-relieving...

Thanks a lot! I thought the aixal expansion of a hollow vessel is free but the raidal expansion of a hollow vessel is limited by itself. It seems I am wrong.

TGS4,I agree with you if you mean vessel axial thermal expansion. How to calculate the radial thermal expansion of a cylinder vessel?

I am working on a thermal expansion estimate of the nozzles on a cylinder vessel for the purpose of piping stress analysis. Could you please give me some advice or referecne materials to calculate the thermal movement of the nozzles on a vessel. I appreciate your help greatly!

Thanks, BigInch. It is the thing I want.

I got a vendor drawing from Germany. The pump outlet marks with "ZX-M 200, 8"". I know the pump nozzle is 200 mm (8"). But I am not sure the connection type (flanged, welded or grooved), and what the meaning of ZX is. Any advice will be appreciated greatly!

Hi, Prex. What is the source of the external pressure equation in your post? Is it for buckling analysis?

Thank you guys! MJC, I read ASME B31.3 again and move forward to ASME -VIII for external pressure evaluation. And Pressure Vessle Design Handbook recommended by BigInch provides excellent reference as well to get the minimum required thickness. But when I use those reference, I find that all the...

Hi, all, I am working on a suction gas duct (thin wall big size CS duct) with negative internal pressure. and wondering how to calculate the minimum duct wall thickness to avoid collapse? I searched the ASME B31.3. The code only gives minimum required pipe wall thickness due to positive internal...

Thanks for all of you.

Thank you so much for your great help on our new pipers. I still need some time to digest your points and get the idea about the ELoops.