Patent ID: 6386148
Filing Date: 2002-05-14
Classification: F04B,F22D

Abstract:
A steam-raising system comprising a boiler having (a) a passageway for water and/or steam, (b) and inlet to the passageway through which water is introduced continuously for given periods when the boiler is in use, (c) a burner to heat the passageway from the outside thereof, and (d) an outlet from the passageway from which steam emerges continuously as water is introduced through the inlet, the system further comprising a pump connected by a flow-path to the said inlet to pump water thereto along the said flow-path, wherein the pump is a variable-flow-rate pump constructed to provide a flow-rate through it which is substantially independent of its downstream pressure, temperature monitoring means are provided downstream of the boiler to measure the temperature of the steam output of the boiler, and a control unit is connected to the temperature monitoring means to adjust the flow-rate of the pump in dependence upon the measured temperature of the steam output of the boiler.