Regarding boiler flange issues
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There is a boiler of the model DZL2-1.25-AⅡ; the standard for its steam outlet flange is JB/T81-94, and the material used is Q235-B and GB700. Can a steel plate cart be used? Why?
It should work. The processing complies with relevant standards such as the Technical Conditions for Pipeline Flanges JB/T 74-1994.
There is a boiler of the model DZL2-1.25-AⅡ, GB700. Can a steel plate cart be used? Why can’t steel plate components be used? Forged parts must be employed, as stated in Article 23 “Table 3-1: Steel Plates for Boilers” of the “Regulations on Safety Inspection of Steam Boilers”: The applicable range for Q235-B steel plates is when the operating pressure is less than or equal to 1.0 MPa. However, the steam outlet pressure of the given boiler (DZL2-1.25-AⅡ) is 1.25 MPa, which is greater than 1.0 MPa; therefore, steel plate components made of Q235-B material cannot be used for its steam outlet flanges.
The answer on the 3rd floor is completely correct! If you are DZL2-1.0-AⅡ, it can be used; therefore, you must use a forged flange made of 20/GB699 material! Most boiler manufacturers use 20II flanges; for specific details, refer to the standard JB-T9626-1999 \"Technical Requirements for Boiler Forgings\".
Agree with the comment above. Q235 cannot be used for your boiler pressure as it exceeds its pressure tolerance range.
Use directly the Q245R GB713-2008 standard, originally 20g
Agree with the opinion from the third floor. The output of the given boiler is not high. But the pressure level is quite high. A boiler is a pressure vessel. Its material must meet the standards. At the same time, the welding electrode used during welding must also be compatible with the pipe material. After welding according to the procedures, flaw detection must be carried out.