Carbon Steel Boiler Superheater And Reheater Different Diameter Butt Joint

Superheaters are the one of the most important boiler sapre parts that improves the thermal efficiency.

Boiler superheater is to recover the energy of boiler flue gas so that the steam out of the boiler can be heated into dry steam, which is conducive to improving the thermal efficiency of the boiler, but also conducive to the steam turbine to avoid water hammer. 

High temperature steam boiler radiant superheater is usually applied in high pressure power plant boiler. Super heater coils are used in a boiler to generate saturated steam. The super heater coils are specially used in Boilers of Power plant. We manufacture Super heater coils in various grades of Alloy steel and in stain less steel tubes with or without support & Header as per customer's drawing.

Changes in boiler operating conditions, such as load level, fuel change, combustion condition change, etc., all have an impact on superheater outlet steam temperature, so in power station boilers there are means to adjust boiler outlet steam temperature to make it stable at the specified value.Commonly used means are:

(1) with water jet or surface type temperature reducer directly adjust the steam temperature;

(2) with the swing burner to change the temperature of the furnace outlet smoke;

(3) with smoke recirculation adjustment superheater heat absorption.When the boiler load increases, the temperature rise value of the inlet and outlet steam of the flow superheater increases, while the temperature rise value of the radiant superheater decreases.

Superheater tube wall in the boiler pressure parts under the highest temperature, so must use high quality low carbon steel and various chromium molybdenum alloy steel, in the highest temperature part sometimes also use austenitic chromium nickel stainless steel. In boiler operation, if the temperature of the pipeline exceeds the allowable temperature limit of the material's durable strength, fatigue strength or surface oxidation, the pipeline burst will occur.

The outer diameter of the pipe is generally 30 ~ 60 mm.The most common type of superheater is the serpentine tube.It has a relatively dense tube set, arranged in the flue gas temperature of 450 ~ 1000℃, by the transverse and longitudinal erosion of flue gas.The flue gas mainly transfers heat to the pipe by convection, and some radiation absorbs heat.Screen type superheater consists of a plurality of tube screen, arranged in the upper part of the furnace or the outlet, belongs to the radiation or semi-radiation superheater.The former absorbs the radiant heat of the furnace flame, while the latter absorbs part of the convective heat.In the power station boiler above 10 mpa, generally both screen type and serpentine tube type superheater are used to increase heat absorption.The wall superheater applied to the inner wall of the furnace is the radiant superheater, which is seldom used.Wall type superheater is used in large capacity power station boiler to form the wall of the furnace roof and convection flue, and the insulation material is applied outside to form the light furnace wall.

Differences

Principle

• Principle of superheater is similar to steam generating tubes of boiler.

• The hot gases at high temperature sweep over superheater tubes and raise the temperature of steam which magnitude depends upon exit gas temperature leaving the superheater and gas velocity.

Application

Use for heating saturated steam, steam temperature could be up to 900 degree C.

Superheater Capacity Upgrades to Increase Power Generation

Send us required technical data, such as steam capacity, presure, required temperature etc. We will design accordingly.