Wire electrode feeder testing - particularly for continuous weld wire

Wire electrode feed devices are tested by (a) unwinding the electrode wire from the rotating bobbin during the test as a result of the tractive force exerted by the feed device, which together with the bobbin is in a state of relative mobility w.r.t. both to the wire and the bobbin, so that during unwinding, the electrode wire and the feed device are subject to mechanical braking resistance balanced and measured by means of a force-measuring element acting equally on the relatively mobile feed device and on the wire resp. in the feed direction or vice versa, and (b) balancing the two forces to represents the force which the wire feed device can overcome as a consequence of the frictional force between the feed rolls and the wire electrode, permitting the test to be carried out with the simultaneous measurement of the thrust, the feed speed and irregularities in it. Tests of wire feed devices including those of planetary type can thus be carried out with a continuous wire electrode over a wide range of speeds, without risk of twisting or kinking of the wire and permitting determination of reliability and length of life.