| 摘要 |
<p>An apparatus (10) for purifying gas distribution systems has a gas inlet (12) and a gas outlet (14) for connection to gas distribution lines (20). A housing (22) encloses a resistance heater (24) and a particle filter (26) for the gas. The resistance heater (24) is connected to the gas inlet (12) and the particle filter (26) is connected between the resistance heater (24) and the gas outlet (14). The resistance heater includes a sealed tube (27) defining a gas plenum (28). A resistance heater element enclosed in a cylindrical Inconel TM alloy shell (30) is centrally disposed in the sealed tube (26). A spiral ridge (32) winds around the shell (30) to define a spiral path for gas flowing through the plenum (28). The spiral ridge (32) has a narrower pitch near the gas inlet (12) and a wider pitch moving toward the filter (26) end of the plenum (28).</p> |
