Hauv kev lag luam khoom noj khoom haus thiab dej haus, kev ntxuav-down yog hais txog cov txheej txheem ntawm kev tsim khoom thiab ua cov khoom siv uas siv cov tshuaj tsuag dej thiab / lossis cov tshuaj muaj zog.Qhov no yog cov txheej txheem tseem ceeb vim tias nws tua cov kab mob thiab lwm yam kab mob los ntxuav qhov chaw uas cov khoom noj khoom haus tuaj yeem tiv nrog thaum ntim thiab xa khoom.

Nws yog ib qho tseem ceeb uas yuav tsum xav txog kev ntxuav-down thaum nqis peev rau hauv cov khoom ntim vim tias koj lub tshuab yuav tsum muaj peev xwm tiv taus qhov corrosive ntawm nquag ntxuav-downs yam tsis ua puas.Cov cuab yeej siv cov hlau tsis muaj steel tiv thaiv corrosion thiab pitting tshwm sim los ntawm cov dej thiab cov tshuaj ntxuav feem ntau siv hauv cov khoom noj khoom haus.