Electric heater, esp. immersion heater for corrosive liq. - has lead with fluoro-plastics insulation, coaxial wire braid and impermeable fluoro-plastics cover

摘要

Electric heating element of the coaxial type with protected leads for aggressive media has fluorinated plastics insulation around the lead, which is covered with wire braid, coaxial with the lead, and then made resistant to diffusion by an outer cover of fluoro-(thermo)plastics. Pref. the insulation is over 50 (80)% covered by the braid and is min. 0.7 mm thick, whilst the outer covering is min. 1 mm thick. The intermediate insulation consists of PTFE and the outer covering of perfluoroalkoxy plastics (which can be applied by extrusion). The element is useful as immersion heater for corrosive liquids. Specifically, a power of 100-200 W/m length can be attained and the bending radius is minimised (ca. 20 times the outside dia. of the cable).