Hot dip galv boltings - temp limits

[samoht]

What is the max recommended design temperatur for Hot Dip Galvanized components (my concern is the surface treatment not the material)? The application is A193 B16 bolts hot dip galv. for corrosion protection.

 

[metengr]

Hot dip galvanizing is done at ~ 820 deg F. For maximum service temperature, I would use 400 deg F. This temperature limit is based on the following reference;

http://www.galvanizeit.org/resources/files/AGA

PDFs/T_HDGF_01.pdf

 

[stanweld]

B16 bolts are generally used for temperatures > 750 F and are not galvanized. In pipe systems operating at high temp., they are normally under insulation. B7 bolts should be used for the lower temp conditions noted by metengr.