Combination of precision blanking and sheet metal forging reduces number of process steps as well as material and energy costs
Automotive components are becoming increasingly complex: they are now expected to fulfil several functions at once in order to save weight. Until recently, such sophisticated parts had to be manufactured in several intermediate steps, pushing the possibilities of conventional forming processes to their limits. One possible solution is the combination of precision blanking and forging in a single die.
“At present, components which have different material thicknesses in different areas are generally produced by joining several individual components,” explains Schuler Managing Director Jochen Frueh, who heads the company’s Industry division. “Long process chains to produce these components and additional steps for storing, separating and loading – as well as the necessary joining processes – all result in high part costs.”
In addition, surfaces often have to be reworked, e.g. to remove the burr. Shortening process chains including all press operations for producing components in a single press therefore offers a huge potential for savings.
Schuler’s sheet metal forging process for progressive or transfer dies has been developed to facilitate the economic production of components with varying material strengths. First, a pre-form shape of the component is produced in a classic sheet metal forming process. Next, one area is thickened or embossed by means of cold forging, e.g. to increase rigidity. Such parts can be produced with a high level of repeat accuracy and close tolerances. For components requiring a higher degree of deformation, Schuler offers hot forming processes.
Toothed flange produced in one passIn the case of a flange component, for example, the required torque transmission in the toothing can be achieved by increasing the sheet thickness from 3.1 to 5 mm. First, the component is pre-formed in a progressive die before the sheet thickness is increased over several stages. Next, the collar is drawn, perforated and thickened in further steps by means of upsetting. Once the component has been cut from the strip, the downstream transfer system takes it, turns it by 180 degrees, places it in the bending station and after that in the station for precision blanking.
Precision blanking – also a development of Schuler –guarantees a high smooth cut ratio and rounds off the burr in the same process. With the aid of additional functions integrated into the press – so-called Servo Modules – a smooth blanked surface is created which is free from fracture and tearing and which can fulfil functions without the need for reworking. As a result, the manufactured components are ready to install.
“The PSK precision blanking and forming presses of Schuler subsidiary Gräbener Pressensysteme are ideally suited for the production of such complex components,” says Schuler Managing Director Jochen Frueh. The line features a servo knuckle-joint drive which allows greater productivity than conventional knuckle-joint presses thanks to its freely programmable stroke heights and movement sequences. It also means that a variety of processes can be integrated – from drawing, bending, embossing, precision blanking and calibrating to welding and joining. The high system rigidity of the PSK presses guarantees close component tolerances while at the same time protecting the die by reducing the cutting impact.n__________________________________The PSK precision blanking and forming presses of Schuler subsidiary Gaebener Pressensysteme are ideally suited for this task_________________________________________________–The combination of precision blanking and sheet metal forging makes it possible to produce highly complex parts_____________________________________________Blanking edges of various materials (clockwise from upper left: 1.4301, S 235, S 700, high-manganese)
