Intermitting Strip Drawing Test Rig

Experimental investigations of deep- and stretch drawing processes are difficult to be evaluated in real tools used for industrial sheet metal forming. Hence, the strip-drawing test is a common method to analyse these processes [*].

The strip drawing allows to simulate real deep drawing and stretch forming conditions and its tribological behavior. For tribological analysis of wear behavior, a strip drawing test setup with blank holder and circular deflection is utilized [1]. This test setup is used to reproduce of the friction conditions caused by bending in the beginning of the drawing edge.

[*] Groche, P.; Filzek, J.; Nitzsche, G.:
Local contact conditions in sheet metal forming and their simulation in laboratory test methods. In: Annals of the German Academic Society for Production Engineering XI/1, Nr. 1. Braunschweig, 2004.

Picture: PtU Bildarchiv

In this setup, a 20 mm wide deburred metal strip passes a modular tool set consisting of drawing edge and blank holder, loaded by a constant force FN,BH. The strip is bent to 90° at the radius of the drawing edge. The measured variables are: blank holder force FN,BH, friction force FF,BH, and tensile force FT.

Strip width: 20 mm
Blank holder area: 100 – 400 mm²
Lubricant amount: 0,2 – 5 g/m
Contact normal pressure: 1 – 50 N7mm²
Sliding speed: till 200 mm/s
Sliding distance per hub: 25 mm