Simple bulge stretching die

The invention discloses a simple bulge stretching die comprising an upper die plate, a locating plate and a lower die plate which are sequentially arranged from top to bottom. The simple bulge stretching die further comprises a locating piece penetrating through the upper die plate, the locating plate and the lower die plate from top to bottom. The locating plate is provided with a cavity used for containing a product. The upper die plate is internally provided with an insert core which slides vertically. The lower die plate is provided with a through hole at the position corresponding to the insert core. The height of the insert core is larger than or equal to the sum between the upper die plate and the lower die plate. When the simple bulge stretching die is used, the simple bulge stretching die does not need to be installed in a stamping or hydraulic device, so that the work load of workers can be lowered, and the production efficiency can be improved; it can be ensured that the product does not generate d