1 General
1.1 Pursuant Laws and Regulations
Cast steel and cast iron vessels and their parts within the jurisdiction of this standard shall be designed, manufactured, inspected and accepted according to the requirements of this standard and other standards relevant to cast steel and iron, thereinto, pressure vessels for cast steel and iron shall also comply with Technologic Supervision Regulations on Safety of Pressure Vessels issued by Department of Labor.
1.2 Scope
1.2.1 For the scope of design pressure and temperature applicable to this standard, specific requirements are as follows according to materials for cast steel and iron:
1.2.1.1 Design pressure of pressure vessels for grey cast iron shall not be greater than 0.8 MPa, and design temperature is 0 ~250℃.
1.2.1.2 Design pressure of pressure vessels for malleable cast iron and spheroidal graphite cast iron shall not be greater than 1.6 MPa, and design temperature is -10 ~350℃.
1.2.1.3 For heat resistant iron castings, 550~1100℃ may be adopted according to different material designations, see Appendix B in Heat Resistant Iron Castings (GB 9437-88).
1.2.1.4 Design temperature of corrosion-resistant high-silicon iron casting components is 0 ~ 250℃.
1.2.1.5 For pressure vessels of cast steel applicable to compression shell, design pressure shall not exceed 6.4 MPa; for those applicable to other pressure components such as flange or flat cover, design pressure may be 10.0 MPa at maximum. Lower limit of design temperature is above - 20℃ (excluding -20℃); upper limit of design temperature: 475 ℃ for carbon and low alloy cast steel; upper limit of design temperature of chrome molybdenum alloy and stainless cast steel is the same as that of plate material or pipe material with the same designation, see Steel Pressure Vessels (GB 150-89).
1.2.2 Requirements for limitation of diameter of pressure vessels for grey cast iron are as follows:
If internal design pressure is less than or equal to 0.3 MPa, inner diameter is less than or equal to 3000 mm;
If internal design pressure is less than or equal to 0.8 MPa, inner diameter is less than or equal to 1000 mm;
If external design pressure is less than or equal to 0.8 MPa, inner diameter is less than or equal to 2000 mm.
1.2.3 Application scope of this standard refers to vessels and cast steel or cast iron parts connected as a whole. Various pipe fittings and pipelines apart from the first flange sealing surface and the first threaded joint connected with casting vessels, and the first sealing surface connected with special connecting piece or pipe fitting are beyond the scope of this standard. So are the plate material, pipe material, bar rolled by other non-casting parts connected with casting vessels such as carbon steel, low alloy steel, alloy steel or stainless steel or parts made by forging process.
1.2.4 Cast iron materials shall not be used for pressure components of pressure vessels of inflammable medium and medium with extremely, highly or moderately hazardous toxicity, or elements of atmospheric vessel with pressure not less than 0.005 MPa, or pressure components of pipe shell heat recovery boiler.
1.2.5 This standard is not applicable to the following various vessels:
1.2.5.1 Directly-fired pressure vessels;
1.2.5.2 Vessels suffering radiation effects;
1.2.5.3 Vessels handled frequently;
1.2.5.4 Vessels requiring fatigue analysis.
1.2.6 Classification of pressure vessels
Cast steel or cast iron vessels in accordance with 3 requirements of Technologic Supervision Regulations on Safety of Pressure Vessels belong to pressure vessels under the supervision of the Regulation.
Cast steel or cast iron vessels with design pressure less than 0.005MPa are atmospheric vessels.
1.3 Design and Manufacturing Organization
1 General
1.1 Pursuant Laws and Regulations
1.2 Scope
1.3 Design and Manufacturing Organization
1.4 Definitions
1.5 Load
1.6 Thickness
1.7 Permissible Stress
1.8 Pressure Test and Compactness Test
2 Materials
2.1 General Requirements of Materials
2.2 Grey Cast Iron
2.3 Spheroidal Graphite Cast Iron
2.4 Malleable Cast Iron
2.5 Corrosion Resistant High Silicon Cast Iron
2.6 Heat Resistant Cast Iron
2.7 Carbon Cast Steel and Acid-Resistant Stainless Cast Steel
2.8 Heat-Resistant Cast Steel
3 Strength Calculation
3.1 General Principles
3.2 Calculation of Tower Vessel
3.3 Calculation of Shells under External Pressure
4 Structural Design
4.1 General Principle and Precautions for Structural Design
4.2 Characteristics of Structural Design of Different Cast Materials
4.3 Design of Cast Node
4.4 Structure Design for Casting Vessel Parts
4.5 Structural Design of Tower Vessel
5 Manufacture, Inspection and Acceptance
5.1 Pursuant Principles
5.2 Materials
5.3 Surface Quality and Allowable Defect
5.4 Heat Treatment
5.5 Casting Tolerance
5.6 Repair of Casting Defect
5.7 General Requirements for Inspection
5.8 Pressure Test and Compactness Test
5.9 Destructive Test of Hydraulic Pressure for Cast Iron Vessel
6 Quality Proof Documents, Painting, Packaging and Transportation
Appendix A Typical Casting Vessels (Reference)
Appendix B Casting Additional Casting Quantity of Castings (Reference)
Additional Explanation
Standard
HG 20531-1993 Cast steel, cast iron vessels (English Version)
1 General
1.1 Pursuant Laws and Regulations
Cast steel and cast iron vessels and their parts within the jurisdiction of this standard shall be designed, manufactured, inspected and accepted according to the requirements of this standard and other standards relevant to cast steel and iron, thereinto, pressure vessels for cast steel and iron shall also comply with Technologic Supervision Regulations on Safety of Pressure Vessels issued by Department of Labor.
1.2 Scope
1.2.1 For the scope of design pressure and temperature applicable to this standard, specific requirements are as follows according to materials for cast steel and iron:
1.2.1.1 Design pressure of pressure vessels for grey cast iron shall not be greater than 0.8 MPa, and design temperature is 0 ~250℃.
1.2.1.2 Design pressure of pressure vessels for malleable cast iron and spheroidal graphite cast iron shall not be greater than 1.6 MPa, and design temperature is -10 ~350℃.
1.2.1.3 For heat resistant iron castings, 550~1100℃ may be adopted according to different material designations, see Appendix B in Heat Resistant Iron Castings (GB 9437-88).
1.2.1.4 Design temperature of corrosion-resistant high-silicon iron casting components is 0 ~ 250℃.
1.2.1.5 For pressure vessels of cast steel applicable to compression shell, design pressure shall not exceed 6.4 MPa; for those applicable to other pressure components such as flange or flat cover, design pressure may be 10.0 MPa at maximum. Lower limit of design temperature is above - 20℃ (excluding -20℃); upper limit of design temperature: 475 ℃ for carbon and low alloy cast steel; upper limit of design temperature of chrome molybdenum alloy and stainless cast steel is the same as that of plate material or pipe material with the same designation, see Steel Pressure Vessels (GB 150-89).
1.2.2 Requirements for limitation of diameter of pressure vessels for grey cast iron are as follows:
If internal design pressure is less than or equal to 0.3 MPa, inner diameter is less than or equal to 3000 mm;
If internal design pressure is less than or equal to 0.8 MPa, inner diameter is less than or equal to 1000 mm;
If external design pressure is less than or equal to 0.8 MPa, inner diameter is less than or equal to 2000 mm.
1.2.3 Application scope of this standard refers to vessels and cast steel or cast iron parts connected as a whole. Various pipe fittings and pipelines apart from the first flange sealing surface and the first threaded joint connected with casting vessels, and the first sealing surface connected with special connecting piece or pipe fitting are beyond the scope of this standard. So are the plate material, pipe material, bar rolled by other non-casting parts connected with casting vessels such as carbon steel, low alloy steel, alloy steel or stainless steel or parts made by forging process.
1.2.4 Cast iron materials shall not be used for pressure components of pressure vessels of inflammable medium and medium with extremely, highly or moderately hazardous toxicity, or elements of atmospheric vessel with pressure not less than 0.005 MPa, or pressure components of pipe shell heat recovery boiler.
1.2.5 This standard is not applicable to the following various vessels:
1.2.5.1 Directly-fired pressure vessels;
1.2.5.2 Vessels suffering radiation effects;
1.2.5.3 Vessels handled frequently;
1.2.5.4 Vessels requiring fatigue analysis.
1.2.6 Classification of pressure vessels
Cast steel or cast iron vessels in accordance with 3 requirements of Technologic Supervision Regulations on Safety of Pressure Vessels belong to pressure vessels under the supervision of the Regulation.
Cast steel or cast iron vessels with design pressure less than 0.005MPa are atmospheric vessels.
1.3 Design and Manufacturing Organization
Contents of HG 20531-1993
1 General
1.1 Pursuant Laws and Regulations
1.2 Scope
1.3 Design and Manufacturing Organization
1.4 Definitions
1.5 Load
1.6 Thickness
1.7 Permissible Stress
1.8 Pressure Test and Compactness Test
2 Materials
2.1 General Requirements of Materials
2.2 Grey Cast Iron
2.3 Spheroidal Graphite Cast Iron
2.4 Malleable Cast Iron
2.5 Corrosion Resistant High Silicon Cast Iron
2.6 Heat Resistant Cast Iron
2.7 Carbon Cast Steel and Acid-Resistant Stainless Cast Steel
2.8 Heat-Resistant Cast Steel
3 Strength Calculation
3.1 General Principles
3.2 Calculation of Tower Vessel
3.3 Calculation of Shells under External Pressure
4 Structural Design
4.1 General Principle and Precautions for Structural Design
4.2 Characteristics of Structural Design of Different Cast Materials
4.3 Design of Cast Node
4.4 Structure Design for Casting Vessel Parts
4.5 Structural Design of Tower Vessel
5 Manufacture, Inspection and Acceptance
5.1 Pursuant Principles
5.2 Materials
5.3 Surface Quality and Allowable Defect
5.4 Heat Treatment
5.5 Casting Tolerance
5.6 Repair of Casting Defect
5.7 General Requirements for Inspection
5.8 Pressure Test and Compactness Test
5.9 Destructive Test of Hydraulic Pressure for Cast Iron Vessel
6 Quality Proof Documents, Painting, Packaging and Transportation
Appendix A Typical Casting Vessels (Reference)
Appendix B Casting Additional Casting Quantity of Castings (Reference)
Additional Explanation
