API 5l M Tope

API 5l B bututu mai tsayi karfe ne mai tsayi tare da m giciye-sashe kuma babu makiyaya a kusa da shi. An yi shi da carbon karfe. Carbon Karfe baƙin ƙarfe-carbon riguna tare da baƙin ƙarfe kamar matrix da carbon a matsayin babban adadin ƙara. Carbon Karfe bututu yana da babban ƙarfi kuma yana iya tsayayya da wasu matsi da tashin hankali.

API 5L Galla Galvanized bututu ne tare da Layer na zinc a saman bututun karfe. Kasancewar zinc na zinc yana ba da bututun galvanized mai kyau acroson juriya. Abubuwan sunadarai na zinc sun fi zafi fiye da baƙin ƙarfe. A cikin muhalli mai lalacewa, zinc zai mutu da baƙin ƙarfe, don haka kare pup ɗin karfe daga lalata.