The classification standards are not harmonious enough. My personal understanding has no basis.

A. Drawing die - a mold used to draw a flat plate into a cylindrical workpiece, generally called a drawing die.

B. Calendering die ---- a die that increases the linearity or area of ??the workpiece by squeezing it.

C. Drop hammer mold ----The mold installed on the drop hammer.

D. Bending mold——a mold used to bend workpieces.