The screw press has no fixed lower dead center. For larger die forgings, it can be formed by multiple blows, and can be single hit, continuous hit and inching. The striking force is related to the deformation of the workpiece. When the deformation is large, the striking force is small, and when the deformation is small (such as cold stroke), the striking force is large. In these respects, it is similar to a forging hammer. However, its striking force is closed by the frame, so it works stably. Its vibration is much smaller than that of the forging hammer, and it does not require a large foundation.