Steel for boiler heating surface pipes and steam pipes-Boiler Tubes,Heat-Exchanger Tubes,Superheater Tubes,Supplier,Beite

Steel for boiler heating surface pipes and steam pipes

Introduction of common materials for boiler heating surface pipes and steam pipes

The following introduces some commonly used pot materials according to the superheater and steam pipe wall temperature (working temperature).

(1) Wall temperature: superheater tube≤500 ℃, steam pipeline≤450 ℃.

Commonly used steel: 20G, German ST35.8, ST45.8, etc.

Heat treatment: hot rolling, air cooling.

Advantages and disadvantages: good manufacturability and low price; pearlite spheroidization and graphitization will occur.

(2) Wall temperature: superheater tube ≤550 ℃, steam pipeline ≤510 ℃.

Commonly used steel: 15CrMo.

Heat treatment: normalizing at 930 ~ 960 ℃, tempering at 680 ~ 730 ℃.

Advantages and disadvantages: no graphitization tendency; pearlite spheroidization and alloy redistribution will occur.

(3) Wall temperature: superheater tube ≤580 ℃, steam pipeline ≤540 ℃.

Commonly used steel: 12Cr1MoV, West Germany 10CrMo910, 2.25Cr1Mo, etc.

Heat treatment: normalizing + high temperature tempering, air cooling at 980 ~ 1020 ℃, tempering at 720 ~ 760 ℃ for 3h.

Advantages and Disadvantages: It has sufficient oxidation resistance; a certain degree of thermal brittleness, redistribution of pearlite and alloy elements will occur.

(4) Wall temperature: superheater tube and steam pipeline ≤600 ~ 620 ℃.

Commonly used steel: 12Cr2MoWVTiB (ie steel 102).

Heat treatment: normalizing + high temperature tempering to obtain bainite structure.

Advantages and Disadvantages: Interaction of a variety of trace elements, good thermal strength and tissue stability, no tendency to thermal embrittlement; poor welding performance, insufficient quality, rarely used in steam pipelines, mostly used in superheaters and reheaters

At present, the further development of new heat-resistant materials that are both high-temperature resistant and inexpensive is the key to the development of high-parameter units.