Flow Direction Through a Pipe Union 1

[BronYrAur]

In my 24 years in this business, I have never heard that there is a preferred direction of flow through a pipe union. Apparently there is for certain applications (e.g. steam, high velocity, etc.) The "nut side" of the union should be the entering side. A quick Google search indicated such. I am willing to accept that this is "good practice", but is it REQUIRED?

Is there a governing authority or a prominent organization such as ASTM, ASME, ASHRE, that recommends this? I am fighting a battle with an end user who says we installed them backwards. Application is low pressure steam for radiators.

thanks

 

[IRstuff]

I would think that if it were required, they would helpfully stamp a direction arrow on the fitting. If it were that critical, they wouldn't leave it to chance.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[LittleInch]

Nah, good practice only, but you can see why. There is a small lip but I can't see it making much of a difference if any, unless you have hundreds

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

 

[jmec87]

No.

In some applications, it is common to flow from the nut side to the external thread side, but this is not required. There are also applications where it may make sense to flow the other direction.

If the end user is claiming you installed them backwards, he needs to show you where in the contract you are required to install a specific way.