公称厚度 meaning in Chinese

nominal thickness
normal thickness

Plates shall be ordered to theoretical weight , the added value to nominal thickness listed in table 2 shall be the theoretical thickness for calculating the weight
钢板按理论重量交货，用表2所列的公称厚度的附加值作为计算重量的理论厚度。
Plates shall be ordered to theoretical weight , the added value to nominal thickness listed in table 2 plus nominal thickness shall be the theoretical thickness for weight calculation
钢板按理论重量交货，用公称厚度加表2所列的附加值作为计算重量的理论厚度。