Control of welding extruder temp. using control appts. - which measures actual temp. of plasticised welding wire at screw end and compares it with set value prior to varying temp., etc.

摘要

The extruder has a conventional heated cylinder and screw at the end of which is a welding nozzle from which the plasticised wire emerges. A temp. sensor between the end of the screw and the welding nozzle measures the temp. of the plasticised material and feeds the value to a control circuit for governing the cylinder heating. A comparison of measured and preset temp. for the given polymer is made and the heating adjusted accordingly to ensure a constant temp. in the emerging welding wire.