1. Yooj yim.
1) Vim yog cov tub ntxhais ib txwm hloov pauv tsis zoo, yog li nws yooj yim tawg.Suitable rau khoov tom qab grooving.
2) Cov tub ntxhais uas tsis muaj kev sib tsoo aluminium-yas panels muaj lub zog zoo thiab tsis yooj yim tawg.
Flatter thiab sib dua.
2. Kev ua haujlwm.
Thaum ua cov txhuas-yas vaj huam sib luag, cov khoom siv ib txwm raug nqi ntau dua kom txuag tau cov khoom thaum txiav, vim tias muaj impurities.