| 摘要 |
<p>A linear cartridge heater has a cylindrical heater element and an integral, concentrically-mounted current collector element positioned within a fire retardant chlorinated PVC enclosure. The enclosure includes a unitarily-molded mounting flange for sealingly mounting the cartridge heater, a unitarily-molded special 'tee' section interconnected with the mounting flange, and an alignment bushing. The alignment bushing is interconnected with the special 'tee' section by a pipe section to form a fluid flow path between the alignment bushing and the special 'tee' section. The special 'tee' section provides an outlet for discharging heated water and a mounting place for a first thermistor temperature sensor. The alignment bushing mounts a second thermistor sensor and concentrically positions the heater element within the enclosure, such that the water flow rate past the heater element is substantially increased by the change from circular pipe flow into the alignment bushing to annular flow about the heater element.</p> |
