NO.4 Finish Sheet

 Qhov No. 4 tiav tseem yog qhov kev xaiv rau cov khoom siv hauv chav ua noj, khoom noj khoom haus thiab dej haus, elevators, escalators, tsev kho mob, thiab txhua qhov chaw uas cov hlau tsis muaj steel tuaj yeem cuam tshuam nrog zaub mov. Pom tau los ntawm nws luv luv, ncaj polishing cov cim, qhov kev ua tiav no kuj yog qhov yooj yim tshaj plaws kom saib zoo rau lub sijhawm. Nyob ntawm seb cov hlau yuav siv li cas, qhov kawg polishing grit tuaj yeem muaj li ntawm 120 txog 320-ntau dua grit tus lej tawm los ua kom zoo dua khawb thiab saib me ntsis ntxiv. Txawm hais tias grit, qhov tshwm sim yog qhov chaw uas nws qhov roughness feem ntau tsis tshaj Ra 25 µin, ua rau nws ob qho tib si huv si thiab tsis tshua muaj txij nkawm.