Superheater and reheater are important parts of gas-fired boiler, which can increase the steam enthalpy value and thus improve the thermal efficiency of the boiler.
The function of superheater is to heat saturated steam into superheated steam with a certain temperature.
The function of the reheater is to heat the exhaust of the high-pressure cylinder of the steam turbine to a reheating temperature equal to (or close to) the temperature of the superheated steam, and then send it to the medium pressure cylinder and the low pressure cylinder for expansion and work.
The superheater and reheater are the parts with high working medium temperature in gas boilers, and the superheated steam, especially the reheated steam, has poor heat absorption ability (the ability to cool the pipe). How to make the metal in the pipe work safely for a long time has become an important problem in the design and operation of superheater and reheater.In the design and operation of superheater and reheater, attention should be paid to the following problems:
1. The steam temperature should be kept stable during operation, and the fluctuation of steam temperature should not exceed 5~10℃.
2. The superheater and reheater should have reliable temperature regulation means, so that the rated steam temperature can be maintained when the operating conditions change within a certain range.
3, try to prevent or reduce the thermal deviation between parallel pipes.