Power Plant Boiler Spare Parts Superheater And Reheater Of Carbon
Steel
Product Description
In modern boilers, the heat absorption consumption of the
superheaters and reheaters is over half of total heat absorption
for the working fluid, thus the heating surfaces of superheaters
and reheaters account for a large proportion in total heating
surfaces of boilers, and they must be placed in the areas where
smoke temperature is higher, the working conditions are the worst
among all the heating surfaces.Tube wall temperature of the heating
surfaces is close to the max. allowable temperature of steel, so
the reasonable arrangement and design of superheaters and reheaters
matter so much for economy and reliability to the while boiler.
When it comes to their design, on the basis of assurance of safety
and reliability of superheater and reheater, it is very necessary
to save metal consumption at the best, especially to save usage of
alloy steel.
For boilers in large power stations, superheaters and reheaters are
necessary parts, to a large extend, they have influnced the safety
and economy of boilers. Superheaters are the heating surfaces which
heat the main steam from the surnatured temperature to the rated
superheated temperature, and the reheaters are the heating surfaces
which heat the exaust from the steam turbine high pressure cylinder
to a certain temperature.When running conditions like boiler loads,
coal types change, it is to adjust them to make sure the outlet
temperature at the rated level of -10-+5 degrees.
For large boilers in power stations, superheaters and reheaters
account for a big proportion in the total heating surfaces, they
are to be arranged in the areas where smoke is with higher
temperature. To improve the efficiency of thermal circulation in
power stations, it is needed to improve the original parameters of
steam gradually, the increase of steam pressure requires the
corresponding increase of temperature for superheated steam, or the
humidity of large stage exhaust of steam turbine will be too high,
which will influence its safety. Thus, the steam flowing through
superheaters and reheaters are high temperature steam, their heat
transfer performance is quite bad, which determines that tube wall
temperatures of superheaters and reheaters are high.
Functions and characteristics of superheaters and reheaters
functions of superheaters and reheaters:
Superheaters and reheaters are important parts for the heating
surfaces, used to increase steam temperature, aiming to improve
steam enthalpy and further to increase the thermal circulation
efficiency for power station.
Superheaters work to heat surnatured steam to superheated steam
with a certain tempetature. When boiler loads or other working
conditions change, it is necessary to make sure superheated steam
temperature to be normal, and within allowable range of temperature
variation.
From the thermal circulation in power station, the original
parameters of pressure and temperature is higher, the thermal
efficiency of circulation is better, or the steam humidity of the
steam turbine rear is too high, influencing its safety. While the
superheaer steam temperature is limited by metal materials, at
present, due to limitation of metal materials, superheated
temperature for most power station boilers are still within the
range of 540-555 dgrees, and to avoid the steam humidity of blade
of steam turbine rear too big, thus middle reheating system is
applied.
Functions of reheaters are to heat exhaust of steam turbine high
pressure cylinder to the reheated temperature which is close or
equal to superheated temperature, and then send them to middle
pressure cylinder and low pressure to expand and work to increase
the dryness of blace of steam turbine rear. Usually, the pressure
of reheated steam is one fifth of that of superheated steam.
Application of reheating system can increase the thermal efficiency
for power stations by 4-5%.
So far in our country, units with capacity over 125mw all apply one
time middle reheating system. Double reheating can increase again
the thermal efficiency of circulation by 2%, but the system is very
complicated, it is not applied for national units, but it is common
for large boilers overseas.
| Material | carbon steel, alloy steel , or durable heat steel |
| Tube OD | 10-114mm |
| Tube W.T. | 0.8mm- 15mm |
| Structure | vertical or horizontal |
Company Information
HD Boiler established in 1985, Zhangjiagang Hua Dong Boiler Co.,
Ltd. (trading as HD Boiler), is a professional industrial
manufacturer, producing utility boiler,industrial boiler,HRSG
boiler and all kinds of boiler parts, such as waterwall panels,
economizers, air preheaters, superheaters, headers, spiral fin
tubes, H-fin tubes, heat pipes etc. HD Boiler is located in Dong
Lai Industrial Park, east suburb of Zhang Jia Gang City. The
plant’s location is around 150km Expressway to Shanghai Port or
60km State Road to Suzhou or Wuxi, with transportation extending in
all directions conveniently and quickly.
