The structure of enameling water tank is upgraded from three-segment type to two-segment type. The manufacturing process of water tank is changed from sheet curling and stamping craft to the sheet deep drawing craft. Because of the structure change of water tank

there are much more requirements on enameling property and formability for steel sheet. Baosteel industrial data and Design of Experiments ( DOE) method are used to establish the steel designing and optimizing model

and the special deep drawing hot-rolled steel for enameling water tank is developed successfully. It has been proved by large industrial production that

the reject ratio of deep drawing parts can be controlled down the level of 0. 4%

at the same time

the enameling property is excellent.