| 摘要 |
<p>A tube (10) of heat resistant steel is used as a heating element to head the flow of a mixture of fluidised coal and transportation air. Annular contacts (11,12) to which conductors (13,14) are connected enable power to be applied. The tube and contacts are buried in a sleeve (15) of thermal and electrical insulating material. The sleeve is closed by insulating rings (16,17). The tube is insulated by heat resistant rings (18,19) fixed under the insulating rings to provide insulated extension sections of tube. On one of these sections is wound thermoelectric resistance windings (22,23) in heat insulating sleeves (24,25). These provide resistances for a Wheatstone bridge containing calibrated resistances (26,27) to permit indication in the temp. rise from which mass flow is determined.</p> |
