Verfahrensgrenzen beim Spaltprofilieren

Extension of ascertained process limitations of linear flow splitting

 

Motivation

The new massive forming process Linear Flow Splitting enables the forming of bifurcated profiles made of sheet metal in integral style. The forming process uses obtuse angled splitting rolls and supporting rolls to increase the surface of the band edge. High hydrostatic compressive stresses induced in the local forming zone during the process lead to an increased formability of the material and thereby to the realization of large strains. The extension of ascertained process limitations and the further processing of the web and the free flanges are at the center of future investigations to increase the spectrum of producible geometries and product properties.

Figure 1: Process principle linear flow splitting
Figure 1: Process principle linear flow splitting

Objectives

In the first step, a continuous production line for the new technology of linear flow splitting will be realized. The main objectives are the realization of process-safe high splitting depths and variable flange thicknesses. Further processing of the web with a roll forming process offers the opportunity to produce profiles with new cross-sections from sheet metal. Therefore, suitable technical stages have to be developed and realized. Splitting the free flanges of a profile made with linear flow splitting facilitates the enhancement of the order of bifurcation. The new geometries offer further construction pros-pects for load adapted cross-sections.

Approach

Suitable modifications of the process will be investigated to produce parts with long flanges and defined properties by achieving high splitting depths in a continuous production line. The main process characteristics will be determined and optimized.

A new tooling system to split the free flanges of parts made with linear flow splitting will be realized. The investigations focus on the process limitations and the possibilities to increase the order of bifurcation. Further processing of the web with roll forming enable the production of profiles with new cross-sections from sheet metal e.g. multi-chambered profiles. Experimental and theoretical investigations will deliver typical process limitations and failure cases for further optimization.

Results

Produced parts are characterized by increased stiffness, high surface hardness (up to 50 %) and low surface roughness (Rz,max=1,6 μm) of the heighten surface.

Figure 2: Produced part made by linear flow splitting
Figure 2: Produced part made by linear flow splitting