Dust Collection Round Ductwork at -60" WC Design Criteria Needed

[Tim37]

In SMACNA 005, "Round Industrial Duct Construction Standards" the Table of support spacing and stiffener requirements only goes as low as -30 inch WC. Does anyone know of tables going lower to -60 " WC, about -2.5 psi. Any suggestions as who I could contact for assistnace in developing criteria?

 

[pipesnpumps]

Not the answer you are seeking, but I would look into just using schedule 10 piping.. It is probably going to be cheaper than welding all the stiffening rings you are going to need.

Piping is good for full vacuum. At least there is a standard that covers it.

I am not personally aware of any software that would do the calcs. ASME piping codes defer to boiler and pressure vessel code for calculating for external pressure. That would be another option to look into.




Real world knowledge doesn't fall out of the sky on a parachute, but rather is gained in small increments during moments of panic or curiosity.

 

[MechEngNCPE]

Funny, I came across this today, but mine only had to be rated -30. We are using galvanized steel pipe with Morris coupling

 

[Tim37]

Today I made a ductwork model in Compress (vessel design software.) The model looks like a long vessel. I entered 0 internal pressure, 2.5 psig external, A240 material, and wind and seismic criteria and other data. The resulta gave me 0.1875" wall (7 gauge) and support spacing distance. I'm going to have someone more familiar with the program check it. But I think the approach is fine.

Any comments on this approach?