| 摘要 |
<p>The workpiece is placed in a lower die in a frame carrying a main work cylinder which can be driven axially; in the cylinder is a hollow piston with a hollow piston rod projecting downwards. In the rod is a hammer carrying a punch driven into the workpiece. Above the piston is an explosion chamber used to drive a ram towards the hammer inside the rod. Hammer pref. has a head forming a piston in the rod below an elastic piston; and compressed air is pref. used to lift the piston in the cylinder, and also to lift the hammer in the rod. The elastic piston may be rubber or a liq. Water is pref. used to raise or lower the cylinder in the frame. Used e.g. in the shaping of gas turbine blades made in heat resistant Ti alloys.</p> |
