Mold and preheat
The shape, size, and strength of the mold should be determined based on the product shape, size, temperature, and the linear expansion coefficient of the material; the mold material can be determined according to the degree of deep-drawing deformation and the number of products, generally low-carbon boiler steel or cast iron is used, if the product quantity is greater than For 10,000, wear-resistant tool steel molds can be used. When deep drawing at high temperatures, the tempering temperature of the mold should be 10°C higher than the operating temperature.
The heating element can be used for preheating, and drawing a complex shaped workpiece is preferably done with a burner with an annular flame nozzle, and the punch base is also preferably preheated. If the deviation of the convex dimension of the workpiece is strict, an independently controllable burner shall be provided outside the mould.