| 摘要 |
<p>A steam-raising system comprising a boiler (42) having (a) a passageway (86) for water and/or steam, (b) an inlet (40) to the passageway (86) through which water is introduced continuously for given periods when the boiler (42) is in use, (c) a burner (88) to heat the passageway (86) from the outside thereof, and (d) an outlet (44) from the passageway (86) from which steam emerges continuously as water is introduced through the inlet (40). The system further comprises a pump (32) connected by a flow-path (38) to the said inlet (40) to pump water thereto along the said flow-path (38). The pump (32) is a variable-flow-rate pump (32) constructed to provide a flow-rate through it which is substantially independent of its downstream pressure. <IMAGE></p> |
