What are you want exactly, an way, there are several kinds of these fittings such as 90o elbows, 45o elbows, reducers, ecc.reducers, valves, flanges, bolts , gaskets, minor fittings, and etc.... and of corse there is a certain design for a certain project and conditions. Please for more information tell me what are you want to know.
first you need to design a station then think of transfering and then the question of piping material arises.Yet again what fuel, what temp., what what not required. Please be specific.
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I not only use all the brains that I have, but all that I can borrow. Woodrow Wilson