Ana jujjuya bututun ƙarfe mara zafi mai zafi sama da zafin sake sakewa.Idan aka kwatanta da bututun ƙarfe mai sanyi, diamita na bututun ƙarfe mai zafi ya fi girma, farashin ya ragu, kuma daidaito ya ɗan ƙasa da na bututun ƙarfe mai sanyi.Hot-birgima sumul bututu sun kasu kashi general karfe bututu, low da matsakaici matsa lamba tukunyar jirgi bututu karfe, high matsa lamba tukunyar jirgi karfe bututu, gami karfe bututu, bakin karfe bututu, petroleum fatattaka bututu, geological karfe bututu da sauran karfe bututu.
