1. Ngokwemilo yecandelo lomnqamlezo wesikhwama sokucoca uthuli, inokwahlulwa ibe: izikhwama ezinqamlekileyo (i-trapezoidal kunye ne-flat) kunye neengxowa ezijikelezayo (cylindrical).
2. Ngokwendlela yokungena komoya kunye nemo yokuphuma, inokohlulwa ibe: indawo yokuphuma yomoya esezantsi kunye nendawo yomoya ephezulu, indawo yokungenisa umoya ephezulu kunye nendawo yokuphuma yomoya esezantsi, kunye nohlobo oluthe ngqo lwangoku (ulinganiselwe kwipleyiti{1}}iingxowa ezimcaba ezimile).
3. Ngokwendlela yokucoca isikhwama sokucoca uthuli, inokwahlulwa ibe: uhlobo lokucoca lwangaphandle kunye nodidi lwangaphakathi lokucoca.
4. Ngokuhambelana nobushushu bokunyamezela kweengxowa zokucoca uthuli, zahlulahlulwe zibe: uhlobo lobushushu obuphezulu, uhlobo lobushushu obuphakathi, kunye nohlobo lobushushu obuqhelekileyo . 5. Amasimi eSicelo Amasimi eSicelo: intsimbi kunye nentsimbi yokusila, izityalo ze-ferroalloy, izityalo eziphikisayo, iziseko, izityalo zamandla, izityalo zesamente, izityalo zekhemikhali, izityalo zokulungisa ukutya okuziinkozo, izityalo ze-carbon black, izityalo ze-aluminium, njl.
(1) Uhlobo lobushushu obuphantsi, obulungele abaqokeleli bothuli lwengxowa kwiindawo zothuli zasekuhlaleni ezifana nezixhobo zokusila, iisila zesamente, phezulu nasezantsi kwezisele, njl. njl., kwaye xa zisetyenziswa phantsi kweemeko zokufuma okuphezulu, umphezulu kufuneka uphathwe nge-oyile{2}}iarhente yokugxotha kunye neyokunyanga amanzi;
2