Lub ntsiab siv ntawm caping ncu suav nrog cov hauv qab no:
Txhim kho cov khoom hardness thiab hnav tsis kam: los ntawm kev kho kom sov, li kev kho kom haum rau cov khoom lag luam thiab hnav cov khoom lag luam ruaj khov.
Txhim kho cov khoom lag luam kub tsis kam: cov khoom kho tau los ntawm kev kho lub qhov cub, vim tias tus neeg kho tus neeg sawv cev muaj qee yam khoom siv tau muaj ntau dua.
Txhim kho cov khoom siv tshuaj tiv thaiv: cov khoom kho yog tsis yooj yim cuam tshuam los ntawm cov tshuaj lom thiab muaj cov tshuaj muaj zog corrosion.
