Electric welding surface for thermoplastics - - with close temp control

摘要

An annular electrode of corrosion-resistant steel, large enough to cover the whole welding area, is connected to the secondary winding of a transformer and is fitted with a thermostat which controls the supply. Protruding from its circumference to its centre, the electrode has a narrow tongue, to ensure uniform current distribution. On one or both sides of the surface there is a ring of thermally conducting material, electrically insulated from the surface itself but held firmly to the surface by screws.