Abstract: A three-dimensional numerical model is established to simulate the double vertical explosive welding process of two pairs of clad plates and their collision with the preventive device,and the distribution of pressure field and velocity are obtained during the explosive welding of clad plates.The maximum velocity of the clad plates and collision pressure are calculated with the established model that can be used to design the preventive device.With the double vertical explosive welding process and preventive device,almost two thirds of the explosive charge volume could be saved,and no apparent deformation took place to the clad plates during double vertical explosive welding.