| 摘要 |
<p>1. Electric gas heater comprising an isolated refractory envelope (1) of oblong shape provided at one end with an opening (2) for the inlet of the gas to be heated and at the other end with an opening (3) for the exit of hot gas and a multiplicity of electric heating resistors (4) arranged inside the envelope (1) in a cross direction to the latter, characterized in that each resistor (4) is surrounded by a multiplicity of dead tubes (5) heated by radiation.</p> |
