Recent content by MechEMain

Hi there, If a vessel is under external pressure, can UG-37 be applied to nozzle reinforcement calculation? Thank,

We are going to drill a 1/2" hole on a 1.5" blind flange. And then use a 1/2" nipolet as a connection. Is this acceptable? Can a nipolet be welded to the flange? Thanks?

Thanks for all your help. I read UCS-56 table for P1 material. In note 2a, it says PWHT is required for welded joints over 1/5" nominal thickness. Is this nominal thickness the maximum thickness of the plates or the weld size? In my condition, two plates are welded together with a groove weld...

Hi, I am trying to determine a MDMT for a vessel which is made of SA 516-70N. My question is: 1. Is SA 516-70N still P1 material? 2. If this vessel is post weld heat treated? Can I apply UCS-68(c) to this vessel? 3. How will PWHT affect a normalized material? Thanks,

Thanks, unclesyd. This pressure should be different with different side of pigtails and also varies with materials. I wonder if there is any way to calulate based the size and the material of the pigtails.

unclesyd, Yes, it is pinching off a tube at the pigtail on the furnance.

Sorry, the valve is a globe valve. I have a new question, if we remove the top part of the broken stem, can the pressure of the line push the rest of stem and open the valve? The line pressure is running at 50psig. Valve size is 6".

Does anyone know how to decide at what pressure the pinching should stop so that the tube is not over pinched or not pinched enough? Thanks,

Hi Anegri, This valve is rising stem gate valve. It is used in our 50lb condensate. I cannot find the manufacture of this this valve. So I don't know what the stem material is. But there is no bending on the stem. So I don't think it is broken because of bending.

Thanks, jte. I usually use SEC VIII Div.1. But which part of Div1 is for rectangular vessel? I am designing a leakbox which will be like a rectangular vessel.

For rectangular vessel, what code should I use for tmin calculations? Thanks,

Thank you all for the tips. I had a look in the field. This valve cannot be welded since it broke right at the packing. I don't know if it is broken because of the structure of the stem or the valve got stuck.

If a valve stem is broken, can it be welded back together in field?