1 reply to this topic

[WilliamN]

On an exchanger drawing I inherited, it is spelled out that  tube to tube sheet joint is strength weld, tube hole grooving not allowed, and expanding of tubes in tube sheet not allowed.

 

For this service, leak from one side to another side should be prevented. I thought the joint type of strength weld with grooving and with expansion is the best you can get , and surely better than strength weld without grooving and without expansion (sorry for the lengthy sentence, I just try not to add confusion). Are grooving + expansion not compatible or not allowed by certain codes when  strength weld is specified? Or is this specification just a personal preference from the previous designer?

 

Really appreciate comments from experts from our community.

[Art Montemayor]

WilliamN:

 

Before a REAL expert in this subject matter -  such as SRFISH -  gets onboard and addresses this topic, I think a couple of items have to be clearer up or brought out:

• What kind of tube bundle are you having?  Is it a U-tube (free expansion), or a fixed tube bundle?
• What are the specific fluids involved in the tubes and in the shell?  What is the level of risk should both fluids mix?  Why not employ a double tube sheet?
• Are you really meaning a 100% SEAL weld between tubesheet and tube or a STRENGTH weld?  Is the strength of the weld the key issue or is a positive seal between fluids the real issue?