Galvanized Pipe Code

[visitor]

Could you tell me what its the piping code designation for galvanized pipe for use in compressed air piping system for 3"diam and smallers.

 

[TBP]

For compressed air, you'd likely use either the ASME B31.1, or ASME B31.3 piping codes. For general plant service, probably B31.1.

The only 2 commercially available grades of galvanized pipe I'm aware of are A53F, and A53B (ERW). I'd stronly recommend the ERW. I've seen some pretty sloppy quality control on A53F (very poor joint along the seam). Also, anytime I've noticed that someone is having problems cutting a good thread on a piece of steel pipe, it's invariably a chunk of A53F.

I'm not a big fan of galvanized pipe anyway. For most plants, if you've got drains on the receivers, and proper air dryers, ordinary steel pipe is fine for compressed air. And in the larger sizes, you can use welded joints.

 

[MJCronin]

TBP,

I agree with your comment about the use of non-galvanized pipe for air systems....... for most applications.

However, I have also seen some pretty nasty external corrosion areas ( caustic soda/municipal waste burning plants) where galvanized pipe, I believe, is a good choice

Just my two cents worth....


MJC