Astm A420 shine daidaitaccen bayani don bututun bututun mai da aka yi na carbon carbon karfe da alloy karfe don ƙarancin zafin jiki. Wadannan abubuwan da suka dace, ko dai na kwarai ko welded, da aka yi amfani da su a cikin bututun matsa da kuma siyar da jirgin ruwa na jirgin ruwa a yanayin zafi. Metals-pipping na iya samar da dukkanin maki huɗu na ASM A420: WPL9, WPL3, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, WPL8, da WPL8.