Commercial Piping

Depends on the pressure the type of gas.

This will give you some of the pressure ratings on black pipe

http://www.engineeringtoolbox.com/a106-carbon-steel-pipes-d_370.html

Thank you for the input, and for the reference url.

Black pipe has corrosion issues, the plant I am working at has black pipe installed for its compressed air distribution system. The engineer prior to me did not install an air dryer which resulted in extremely high levels of corrosion inside the piping which in turn found its way into equipment and process.

While black pipe is cheap to purchase and does the job, it would not be my first choice for containing gases.

Thank you for your input, the corrosion problem is one I had not thought of, good point.

one possible alternative material is galvanized carbon steel it has higher corrosion resistance than carbon steel.

S

corrosion prevention

We recently used plastic pipe from China because there are no regulations in Thailand. Seems to work OK. I hope the installers glued all the fittings 100%.

Plastic pipe for compressed air scares me. PVC can fail suddenly and shatter, which in a compressed air system would result in shrapnel blown about with potential for serious injuries. Verify from supplier and get certification that the plastic pipe is suitable for compressed air, not all plastic pipe can meet that criteria.

Black iron is OK for dry compressed air. So would galvanized, but I have heard of potential issues with zinc flaking off and causing problems with downstream equipment. Best bet is good filters at the end use.

Yes, but, not at the same time.