Forming method for railway waggon wheels - with first mandrel from first die moving material out of blank centre, and second mandrel moving into preformed blind hole

摘要

The method is performed in two stages. In a first press stage, the blank (5) is preformed in upper and lower dies (2, 1a, 1b). A first mandrel (4a) moves from the first die into the centre of the blank, and presses material outwards. In a second stage, a second mandrel (4b) moves into the preformed blind hole. During pressing, the second mandrel maintains a constant distance to the second opposite die (2). The device has two lower dies, each with a mandrel. The lower dies are horizontally moveable relative to the upper die, which moves up and down.