Pipe Hangers - Vapour Service

[00098]

What is the maximum recommended horizontal spacing between pipe supports for 30" standard weight steel pipe?
I am looking at Anvil International catalogue PH 2002, page PH 207 which states 34ft. Unless I misunderstand piping design, I feel that the 34 ft is a "typo".

 

[TBP]

It'll depend on the type & wall thickness of the pipe, applicable code, service, and jurisdictional spin, but the slightly out of date copy ASME B31.1 that I have handy says for 24" pipe in steam, air, or gas service, the maximum suggested span is 42 feet.

The supports are almost always closer together for a variety of reasons - heavy fittings like valves require more support, ease of installation for the fitters when they're installing the pipe run, etc.

 

[zeven]

Max span depends on 2 main criteria:
1) Stress - B31.1 suggests limiting max bending moment stress to 2100 psi
2) Deflection at mid span. If this is excessesive you will get condensate collection. Again B31.1 suggests a limit of 0.1", but I would guess the actual limit could be higher, depending on the fall of the pipe (if any).