Dab tsi yog cov khoom ntawm cov nqaij qaib coop?
1. Cov tuab ntawm cov nqaij qaib tawb yog: 2.3 hli
Kab hlau: 2. 2 - 2. 3 hli
2. Cov ntaub ntawv nyoos ntawm khaub thuas-dip galvanizing thiab kub-dip galvanizing yog tib yam (ob qho tib si yog cov roj carbon hlau tsawg),
Nws tsuas yog tias cov txheej txheem ntawm galvanizing ntawm cov nplaim txawv



