1 Parameter series
1.1 Parameters of 200MW or lower class unit
The pipe parameter series reserves the original one in "Typical Design for Steam-Water Pipe Parts and Components (Edition 87)", and it is added with secondary-high-pressure parameter series. With the existing status and development trend of thermal power plant at present, the unit size develops towards high parameter and large capacity, and the small units of 200 MW or lower class develop less and less. The operation practice for years has shown that the parameters of these units, specified in "Typical Design for Steam-Water Pipe Parts and Components (Edition 87)" are applicable basically. The secondary-high-pressure parameters are supplemented in this revision because they are mostly applied in combined cycle and CFB power plants.
1.2 Parameters of high pressure and superhigh pressure units
In "Typical Design for Steam-Water Pipe Parts and Components (Edition 87)", the design temperature of main steam and hot segment in high-voltage and superhigh pressure units is 540℃, leaving out of consideration of temperature deviation; in this revision, this temperature is adjusted to 545 ℃.
1.3 Parameters of subcritical units
These are selected by screening from the parameters of the domestic existing and under-construction units, which cover the larger range of the parameter, without regard to overpressure operating condition. The units exceeding these parameters will be considered according to the unconventional parameters.
1.4 Parameters of supercritical units
Some supercritical units have been put into operation in China, but the parameter applied has great difference, and "Typical Design for Steam-Water Pipe Parts and Components (Edition 2000)", hereinafter referred to as "the Typical Design", specifies such parameters according to the ones of
