Dear Experts,

I'm currently analyzing flare line system. Problem arise when I asked a reinforcement pad on lateral tee connection which is at first i assume that would be un-reinforced lateral tee. Later my manager said that company will buy "Seamless Lateral Tee" and the SIF will be much lower than reinforced lateral tee.

I usually model the reinforced lateral tee as type reinforced SIF and un-reinforced tee as type unreinforced SIF at caesar (reference)

My question: is it correct to model the seamless lateral tee as type welding SIF at Caesar?? or what SIF type is more conservative? FYI, we don't have FEA software.

Please advise and Thanks.

You may refer to Piping Handbook by Nayyar. In this book, there is chapter about SIF of lateral branch connections, see page B.126 and B.147. But take note that your lateral tee is of seamless type.