Pre galvanized square steel tubes are made from galvanizes steel sheets.It is different from the hot galvanizing , which is done after the tube production. Since the production process is simple, cost is much less than latter one. The zinc thickness for pre-galvanizing is about 150-200g/m2 , 400-500g/m2 for post-galvanizing.
Pre-galvanized square steel tubes are limited when it comes to the sizes.
Pls kindly check it as below:
Size/inch Dia/mm WT/mm Size/mm WT/mm Size/mm WT/mm