Elongated metallic element bending process - detects heated zone temp. or clearance between element and heater for adjustment from comparison with reference value

摘要

Pressure (2) is applied axially to one end of the tube or bar (1) while its other end is constrained within a collar (5) attached to an arm (3) rotating about an axis (4). An intermediate cross-section of the element (1) is softened by the heating effect of an enveloping inductor (6) in close proximity to an air or water cooling ring (7). The max. temp. of the heated surface (or alternatively the clearance between the heated surface and the inductor) is monitored by pref. four reciprocating detectors inclined so as to scan the whole area without interfering with the heating element (6). The detectors are connected by fibre optics to a peak detector/recorder with a digital display. The variable-geometry inductor (6) is adjusted to vary the heating effect according as the local temp. (or clearance) is greater or less than a desired value.