Connection types (FF, RF, RTJ, NPT)
Connection types (FF, RF, RTJ, NPT)
(OP)
What do you use to determine what type of end connection you will use on a fitting.
For instance when do you use ring joint instead of a raised face or flat face
What about NPT connections?
The reason I am asking is I have seen some use 600# RTJ and then use 600# RF later.
My initial thoughts are the smaller sizes use NPT because a flanged connection would be impractical
For instance when do you use ring joint instead of a raised face or flat face
What about NPT connections?
The reason I am asking is I have seen some use 600# RTJ and then use 600# RF later.
My initial thoughts are the smaller sizes use NPT because a flanged connection would be impractical
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RE: Connection types (FF, RF, RTJ, NPT)
FF is only for cast iron, low pressure stuff #125, #150 or plastic flanges where low bending stress is allowed
RF goes from #150 upwards. Where you stop is more depenadnat on who you work for or what your plant piping spec says than anything else.
You don't often see #600 RTJ, but some companies love them so put them on #300 flanges. NPT is more common for instruments and items of 1" and below as flanges of that size get bulky and weigh a lot compared to the pipe size.
You will find as many ideas and thoughts as there are people commenting here....
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Also: There's usually a good reason why everyone does it that way