This document specifies the basic requirements, application scope (temperature and pressure) and permissible stress of pressure parts, load-bearing members and other materials of shell boilers, as well as the selection requirements for welding materials.
This document is applicable to the material selection and use for pressure parts, load-bearing member and welding materials of shell boilers defined by GB/T 16508.1.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
JB/T 3375 Rules for receiving acceptance of materials for boiler construction
JB/T 9625 Specification for pressure retaining casting of boiler pipe fittings
NB/T 47008 Carbon steel and alloy steel forgings for pressure equipment
NB/T 47013.3 Nondestructive testing of pressure equipments — Part 3: Ultrasonic testing
NB/T 47018
(all parts) Technical permission of welding materials for pressure equipment
NB/T 47019.3 Purchase technical specification for boiler & heater exchanger tubes/pipes — Part 3: Non-alloy and alloy steel with specified elevated temperature properties
YB/T 5092 Stainless steel wires for welding
3 Terms and definitions
For the purpose of this document, the terms and definitions specified in GB/T 2900.48 and GB/T 16508.1 apply.
4 Design and material selection
4.1 Basic requirements
4.1.1 The steel used for boiler pressure parts and load-bearing members welded with pressure parts shall be killed steel, and elements not specified in material standards shall not be added to the materials without the consent of boiler fabrication organization.
4.1.2 The materials for boiler pressure parts and load-bearing members and welding materials shall have the designations included in national or industry standards, and shall be those specified in this document. Materials other than those specified may be used if they meet the relevant requirements of this document; the selection of materials with foreign designations and new materials shall meet the requirements of GB/T 16507.2.
4.1.3 The longitudinal percentage elongation after fracture (A) of steel plates, steel tubes and steel forgings for boiler pressure parts shall not be less than 18% at room temperature after tensile test with standard samples; the absorbed impact energy (KV2) of V-notch Charpy impact test shall not be less than 27J at room temperature.
4.1.4 The deformation ratio of steel plates, steel tubes, forgings and round steel for suspenders used for boiler pressure parts shall not be less than 3.0 when rolled or forged directly with cast billets (including moulded and continuously cast ones).
4.1.5 The material fabrication organization shall ensure the quality of boiler steel and provide relevant data related to material quality certification. The specific requirements are as follows:
a) The material fabrication organization shall provide the original material quality certificate to the user according to the corresponding material standards and the order contract. The material quality certificate shall be complete, printed with traceable information identifier and stamped with the quality inspection seal of the material fabrication organization;
b) When providing materials, the material operation organization shall also provide the original material quality certificate or its copy stamped with official seal of the material supplier and the signature (seal) of the responsible person.
4.1.6 The boiler fabrication organization shall check and accept the boiler materials according to the items specified in JB/T 3375, and cannot use them unless they are
Foreword i Introduction iv 1 Scope 2 Normative references 3 Terms and definitions 4 Design and material selection 5 Materials for pressure parts 6 Materials for bearing components 7 Welding material Appendix A (Informative) Elastic modulus, thermal conductivity and expansion coefficient of common materials Appendix B (Nominative) Metallographic examination for steel forging Bibliography
