I m doing one analysis for large diameter pipe. Where the D/t ratio is 140.
The pipe size is 1400dia & 10thk.

The code stress is failing at TEE portion during Wind analysis.

If i provide the TEE thickness & Reiforcement Pad 20mm thickness, it passes the code stress(but the connecting pipe thickness is 10mm)

1. Whether increasing the TEE thick & providing the pad is the only solution for reducing the SIF value of TEE or is there any other methods.

2 Whether providing the Stiffners over the TEE is the standard method for reducing the SIF value. I want to make my TEE (10mm thk & 10mm reinforcement pad) equal to what i arrive the SIF value for 20mm thk. & 20mm pad, is it possible by providing the stiffners.

Thanks & Regards

Okay I'll be glad to do a detailed FEA model under contract to you and provide you the finished design answers you require! I'll submit my proposal to you shortly....

You are welcome sir. I m asking only a suggestion whether is it possible or not, since i don't know much about that.

Your high stress is basically M*i/Z. You are trying to reduce it now by reducing i. (And this i is questionable in the first place - see other thread on OD/t>100.) Of course you can also reduce M. Do that by adding a support to carry the wind load. Hopefully that won't hurt your flexibility.

Thanks for your suggestions sir. Whether the SIF calculated by CII(as per relevant code) for TEE's where D/t>100 will it be more or less equal to FE value.

Whether is it must to do FE for TEE's & Mitre bends where D/t>100 to find SIF value.

Gee thats what the code implies does it not? what more do you need???? 16 Pt Bold in caps???

Asking all the people on the internet on every forum that exists for their opinion is really not being responsible...

Add metal and hope for the best and quit trying for a FREE exact answer!

John sir...pls...let others to post. My humble request.

Is it correct Procedure to increase the TEE Thickness & Reinforcement Pad to reduce the Bending Stress value (The Pipe thickness is 10 mm & the TEE thickness is 20mm & Pad thickness 20mm).

see post above.... "Add metal and hope for the best"

Sir, Just now i red the COADE Newsletter Dec98 where it has given clearly how to model the large diameter TEE's.

It covers modelling of Large Diameter Pipe & Smaller Diameter Branch TEE.

But in my case it is Equal TEE (1400x1400). Nearly the branch starts from the Centre of the Pipe, in this how to model the TEE, whether dummy element requires ?

Follow the newsletter advice and use a weightless rigid from the center of the TEE to the OD. You will have to enter the "branch" point SIFs manually. For a First pass analysis just use the Code calculated SIFs, BUT you will need to follow up with calculated SIFs from FEA, vendor, ...

Sometimes the Inplane SIFs may be comparable, but the OUTPLANE Code SIFs are usually much Lower (unconservative) than "actual" SIFs from an FEA calc.

Also, the weight loads are more accurate, especially if fluid or refractory is involved.

But in my case it is Equal TEE (DN1400xDN1400). Nearly the branch starts from the Centre of the Pipe, in this case whether dummy element requires ?

Moorthi,
To over come fabricating a pad you have a simpl way to get round this suitation which I did several times.
You can use higher SHD for the tee and by this it will pass the failure and the difference between pipe thk and tee wont be this big!!

But in my case it is Equal TEE (DN1400xDN1400). Nearly the branch starts from the Centre of the Pipe, in this case whether dummy element requires ?