Rationale

The current specification dictates that low carbon in Type I enameling steel is obtained through sheet decarburization. Low carbon levels required by the Type I specification may also be achieved through melt practices with the resultant steel exhibiting all the attributes of current Type I enameling steel. The current proposed ballot aims to add Type Ia enameling steel compositions which do not require the use of sheet decarburization. Type Ia grade shall be supplied only when specifically requested by the purchaser. In absence of a specific request for Type Ia, the supplier shall provide the customer with sheet decarburized Type I. The proposed change(s) will not impact existing Type I enameling steels made via sheet decarburization. Additionally, the proposed changes, as noted in sections 4.1.1 and 5.1.6, will not impact the current limits on chemical composition as defined in Table 1 of ASTSM A424.