castings, forging qhov chaw thiab steel siv qhov chaw rau clearing me ntsis viscous xuab zeb, xuab zeb core thiab oxide daim tawv nqaij. Nws kuj tseem tsim nyog rau kev ntxuav thiab ntxiv dag zog rau qhov chaw kho cua sov, tshwj xeeb tshaj yog rau kev tu me ntsis, nyias phab ntsa uas tsis haum rau k......
Nyeem ntxiv