Union fittings and flow

[AIMFish]

I just installed a union fitting yesterday and I wondered if it was supposed to go a certain way depending on flow? Male to female or female to male following flow. It probably doesn't matter but I wondered what others thought or knew. Thanks in advance for your time and info.

 

[tekknoschtev]

I dont think it matters, we always just position the "screw" part in such a way that it is more convienient to get to.

 

[kgross]

I don't think it matters either. Normally I place the nut on top just so I don't have to try and hold it up while screwing it on. I do have to pick it up to take it apart though...

Kim

 

[BeanAnimal]

It is usually prudent use use the next larger size of union (and ball valve). The unions (and ball valves) typically have a very small ID compared to the rest of the pipe and fittings.

I use the next size up and a reducing bushing in each end. The reducing bushing has a larger ID than the appropriate sized union.

The TRUE UNION valves are even worse. I ALWAYS step up a size when using a true union valve.
Just something to think about.

 

[kgross]

To follow up with what Bean said, if you are looking for max flow always upsize your plumbing. If you think you need 1 inch, use 1 1/4 that way the fittings and valves you use will create very little restriction to the flow. If you need lots of fittings and valves upsize by 2 sizes, ie from 1 inch to 1 1/2, that way even if you have to make the whole pipe out of elbows you will still have less friction loss than making it all out of 1 inch.

Kim

 

[AIMFish]

Good idea about stepping up guys. Thanks for the info and ideas.