Improvements in Metal Punches.
Реферат: 13,143. Rigby, H. June 27. Punching.-A punch for punching parallel or finished holes in metal plates has a conical centre c, a preliminary punching - disc U of truncated conical form, and a finishing cutting-edge b. The thickness x of the disc C is about one quarter that of the plate to be punched, and the distance y about one fifth. The body B tapers ininwards about 3‹ on each side, and the angle of the conical surface of the disc C is about 116‹ as shown. Fig. 2 shows the shape of the punched-out piece.
Method and plant for air quality improvement in restricted space
Номер патента: RU2338961C2. Автор: Лауфей ЛИН. Владелец: Лауфей ЛИН. Дата публикации: 2008-11-20.