In my understanding of the code, this is somewhat left up to the engineer. I do alot of design work on non-standard valves or "valve-like" components and systems, so make these decisions regularly. At a mionimum, ask yourself "If this material fails, what will happen". If...
You might check the ASM website - thye have a new program which is supposed to be a great cross-reference of materials, I am just now looking into it and cannot vouch yet for it, but person who told me about it had used it successfully
www.asminternational.org/materialsinfo
Very application specific question. I reularly see systems for loading and unloading similar oils (at blending plants) into tank cars where the velocity is 10-15 ft/s, and most gas and diesel is loaded at 15 ft/s and higher. For these, systems have lasted 15+ years with schedule 40 A105 piping...
I am trying ot create flow graphs based on a calculated Cv value, with pressure loss shown in PSI.
Function works and gives me default units of lb*ft^-1*sec^-2, at which I insert psi and all is well
However, when I try to graph it, I get the default units, if I type psi in the y column I get...