Njengoko kubonisiwe kumzobo, oku kufakelwa ityhubhu kwaye ineenzuzo zesakhiwo esilula, ukusetyenziswa ngokufanelekileyo kwaye akukho welding, isetyenziswa ngokubanzi kumashishini ahlukeneyo afana neekhemikhali, amayeza, i-petroleum, umfuniselo wesayensi, ubunjineli bombane, njl. ...
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