20" x 12" Reducer for 720 psig design pressure

[pflow]

Hello,

We need a 20" x 12" Reducer for 720 psig design pressure @ 120 F. Piping is A106 Gr. B.

Per formulas in B31.1, this requires Schedule 40 on the 20 inch and STD wall on the 12 inch.

We found out that "purchased" fittings above 12 inch are only available in STD wall and for the 20 inch, STD wall = Schedule 20 which is below our need of Schedule 40.

Thus, we are considering our options.

One option is to order a Schedule 40 pipe cap (if available or a spun head if not) and stub in the 12 inch with repad. The calculations show the repad will use up almost all of the available space.

Is there a better solution ?

Any suggestions you may offer would appreciated.

 

[Krausen]

If you are stuck with 20" STD wall, could you increase the yield strength of the fitting to handle the design pressure with thinner wall? Say a Y42 or Y52 grade one? I've seen these "high yield" fittings specified to ASTM A860. There is also an MSS spec that can be referenced. Not sure what your design factor is or if you're limited to Grade B fittings/pipe by weld procedures or other reasons?

 

[LittleInch]

pflow

You're just looking in the wrong place to buy fittings. There is no way that the supply of reducers is limited to STD wall thickness above 12".

You need to find a different supplier. - Google is your friend. This in one of very many - search pipe reducer schedule 40.

http://coleindustrial.com/fittings/...oncentric-and-eccentric-reducers-schedule-40/

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[MJCronin]

Agree with LittleInch....

Ditch your supplier.......I can find reducers of the proper wall thickness.

Be aware that in any case, higher schedule fittings and piping can be used in your service. Internally taper the fitting (in accordance with the piping code rules) at the butt weld location.

MJCronin
Sr. Process Engineer

 

[pflow]

Thank you all for the replies. Will consider stronger material and other suppliers (I took at "face value" what the purchasing agent said).

 

[LittleInch]

Get a new purchasing agent who buys what you want, not what his favourite / only supplier can give you...

Many buyers end up thinking they know more about design than the designers. They are rarely correct in that view. That's where Google is your friend.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[racookpe1978]

Will consider stronger material and other suppliers (I took at "face value" what the purchasing agent said).

No, not necessarily "stronger material", but thicker material (larger schedule nbr) of the same material ... but bought from a different supplier.