REDUCER THICKNESS 1

[santanasand]

Help! I am using a 6" x 8" XS WT Reducer as a transition component in a vessel. Since the large end & small end have different wall thicknesses(0.5" & 0.432" respectively), I am wondering if the transition part thickness takes thicker one or varies between these two thicknesses. ASME B16.9 doesn't specify the wall thickness of a reducer. In this case the thinner thickness is not sufficient for the code calculation.If anyone knows the answer or knows the contact information of the manufacturers, please let me know. Thanks in advance!

 

[unclesyd]

The thickness at the ends of the 6X8 XS reducer matches the pipe wall thickness of the corresponding pipe size.

At one time you could purchase a reducer with uniform wall thickness but I don't find them any more.

A quick work around would be to buy a heavier wall reducer and taper the ends to match the corresponding wall.

Come back with a litte more design information as the loss of a fat 1/16" is cutting a design pretty close.

 

[santanasand]

Thanks, unclesyd! What I am concerning is the transition part, not the ends.If I use next schedule SCH 120 6X8" Reducer, then the larger end is 0.719" which requires 1:3 transition length per code. I am afraid 1. the cost of SCH 120 reducer is way more than the XS one; 2. The bevel labour cost; 3. the length for transition may not be sufficient(There is no detail drawing about the reducer).

The required design thickness for the reducer is 0.3829", while 6" XS pipe minimum thickness is 0.432" x 0.875 = 0.378". The two ends connect with both XS 6" & 8" pipes.

Thanks again.

 

[unclesyd]

Unless the code has changed you can use the nominal dimensions of the pipe. There is no need to take a reduction as you have if I understand your problem correctly. I don't think that you will find any thickness less than the .432 nominal for the 6" end in the reducer. I not saying they aren't some with less than .432" but I've yet to see one and we use a tremendous number of reducers.

There are several ways to make transition for pipe wall thicknesses. I can’t say what’s allowed as I don’t have an up to date code.

 

[DSB123]

santanasand,
I don't know what you are worried/concerned about. If a 6"nb Sch XS pipe will withstand the design conditions and the 8"nb Sch XS pipe will withstand the design conditions then the 8" x 6" Sch XS reducer will withstand the design conditions without the need to know the transition thickness as its to B16.9. The ends will be the correct thickness to match the 6" and 8" relative thicknesses. So where's the problem?