Njengokuvula, ukuvala kunye nokulawula isixhobo sombhobho wokungena komoya kunye nokususa uthuli, ivalve yebhabhathane yokungena umoya ilungele ukungena komoya, ukususwa kothuli kunye neenkqubo zokhuseleko lokusingqongileyo kwi-metallurgy, imigodi, isamente, ishishini lemichiza kunye nokuveliswa kwamandla.Ibhabhathane lokungenisa umoya v...
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