Akwai amfani da guda uku don injin ruwa:
1) A cikin nauyi rabuwa ko magnetic rabuwa da Tin Tin Tin Tin Ore da sauran m karfe ors, sau da yawa ana amfani dasu don hana cutar da ta hanyar {{1 to haka.
2) A lokacin da biyu- ire na girma tsari, idan na farko shine amfani azaman kayan aiki da kuma ƙarfin samarwa sun fi ƙarfin aiki. Saboda takalmin sandar wani nauyi yana da yanki mai yawa sama da nauyin ƙwallan ƙwaya yana da ƙasa da na ƙwanƙwar ƙwaya a mataki na biyu na ƙoshin nika.
3) A wasu halaye, yana iya maye gurbin gajeriyar shugaban kai garkuwa da lafiya. Lokacin aiki mai laushi ko ba wuya eres (musamman vercious ores), yi amfani da sandal din don niƙa zuwa 6 300, wanda ya fi ta amfani da gajeren jita. Lokacin da injin da allon suna cikin kewayon da'ira, da aka sa sahihiyar abu mai sauki ne, farashin maɗaukaki ne, kuma farashin ƙura a cikin mitar bita za'a iya sauƙaƙe. Don wuya Ores, yana iya zama mafi tattalin arziƙi don amfani da ɗan gajeren kai ma jifa da kame da kuma sieve don samar da wata zagaye. A cikin ƙira, ko don amfani da injin niƙa ko kuma injin ruwa don yakin neman zabe, dole ne a ƙaddara bisa ga takamaiman yanayi don tsara shirye-shirye don tsara su.
Ana amfani da Rod Mills sosai cikin ƙarfe kuma waɗanda ba na- Minis na ƙarfe, sassan ruwa da sassan kayan aiki don niƙa daban-daban esres ko duwatsu.
