Q:Is there a risk of the zinc coating peeling off after bending or threading?

Hot-dip galvanized layers are zinc-iron metallurgical bonding layers. Bending or threading after galvanizing poses a risk of zinc layer cracking and localized peeling. The larger the bending radius, the lower the risk; thread cutting causes more significant damage to the zinc layer.

It is recommended to complete bending and threading before galvanizing; if galvanizing is necessary, damaged areas must be repaired with zinc-rich materials in accordance with ASTM A780. Minor cracks are within the standard allowable range, but large-area spalling and exposed iron are unacceptable.

Time：13/11/2026 17:38:01