Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
GB/T 18442 Static Vacuum Insulated Cryogenic Pressure Vessel consists of the following parts under the general title:
——Part 1: General Requirements;
——Part 2: Material;
——Part 3: Design;
——Part 4: Fabrication;
——Part 5: Inspection and Test;
——Part 6: Safety Device Requirements;
——Part 7: Rules of Pressure Strengthening for Inner Vessels.
This part is Part 7 of GB/T 18442.
This part is developed in accordance with the rules given in GB/T 1.1-2009.
This part was proposed by and is under the jurisdiction of National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China (SAC/TC 262).
Part 7: Rules of Pressure Strengthening for Inner Vessels
1 Scope
This part of GB/T 18442 specifies the technical requirements for material, design, fabrication and inspection of inner vessel of static vacuum insulated cryogenic pressure vessel fabricated by pressure strengthening (hereafter referred to as inner vessel).
This part is applicable to inner vessel meeting all of the following requirements simultaneously:
a) Meeting the requirements of 1.2, GB/T 18442.1, with contained medium of cryogenic liquefied gas;
b) Its material is austenitic stainless steel;
c) Its nominal thickness is not less than 4mm but not greater than 24mm, and it is composed of single diameter of cylinder and standard ellipsoidal end enclosure;
d) It's subject to pressure strengthening treatment at room temperature.
This part is not applicable to inner vessel filled with medium with moderate or above toxicity hazard degree.
2 Normative References
The following referenced documents are indispensable for the application 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.
GB/T 150 (All parts) Pressure Vessels
GB/T 228.1 Metallic materials - Tensile Testing - Part 1: Method of Test at Room Temperature
GB/T 229 Metallic Materials - Charpy Pendulum Impact Test Method
GB/T 232 Metallic Materials - Bend test
GB/T 2653 Bend Test Methods on Welded Joints
GB/T 3808 Verification of Pendulum-type Impact Testing Machines
GB/T 12160 Calibration of Extensometers Used in Uniaxial Testing
GB/T 14976 Stainless Steel Seamless Tubes for Fluid Transport
GB/T 16825.1 Verification of Static Uniaxial Testing Machines - Part 1: Tension/Compression Testing Machines - Verification and Calibration of the Force-measuring System
GB/T 24511 Stainless Steel Plate, Sheet and Strip for Pressure Equipment
NB/T 47010 Stainless and Heat-resisting Steel Forgings for Pressure Equipment
NB/T 47013.2 Nondestructive Testing of Pressure Equipment - Part 2: Radiographic Testing
NB/T 47013.5 Nondestructive Testing of Pressure Equipment - Part 5: Penetrant Testing
NB/T 47013.11 Nondestructive Testing of Pressure Equipment - Part 11: X-ray Digital Radioscopic Testing
NB/T 47014 Welding Procedure Qualification for Pressure Equipment
NB/T 47016 Mechanical Property Tests of Products Welded Test Coupons for Pressure Equipment
NB/T 47018.1 Technical Permission of Welding Materials for Pressure Equipment - Part 1: General Rule
NB/T 47018.2 Technical Permission of Welding Materials for Pressure Equipment - Part 2: Steel Welding Rod
NB/T 47018.3 Technical Permission of Welding Materials for Pressure Equipment - Part 3: Steel Electrodes and Rods for Gas-shielded Arc Welding
NB/T 47018.4 Technical Permission of Welding Materials for Pressure Equipment - Part 4: Electrodes and Fluxes for Submerged Arc Welding
JB 4732-1995 Steel Pressure Vessels - Design by Analysis (Confirmed in 2005)
TSG 21-2016 Supervision Regulation on Safety Technology for Stationary Pressure Vessel
3 Terms, Definitions and Symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 18442.1 and the followings apply.
3.1.1
strengthening pressure
the reached maximum pressure of the top of austenitic stainless steel inner vessel when it's subject to pressure strengthening treatment at room temperature
3.1.2
pressure strengthened vessel
the vessel of which its shell generates overall plastic deformation and reaches structure stability after stopping applying strengthening pressure for the inner vessel made of austenitic stainless steel which is subject to pressure strengthening treatment at room temperature
3.2 Symbol
For the purpose of this document, the following symbols apply.
A——Elongation after fracture, %;
Di——Inside diameter of cylinder or end enclosure, mm;
KV2——Charpy impact absorbed energy, J;
LE——Side expansion value, mm;
pc——Calculated pressure, MPa;
pk——Strengthened pressure, MPa;
Rm——Tensile strength, MPa;
Rp0.2——Stress, where the specified residue elongation of steel is 0.2%, MPa;
δs——Steel thickness, mm;
[σp]t——Permissible stress of cylinder or end enclosure material at the design temperature after pressure strengthening of inner vessel, MPa.
4 General Requirements
4.1 The material, design, fabrication, inspection and identifier of inner vessel shall not only meet the requirements of all parts of this standard, but also comply with the requirements of relevant laws, regulations and safety specifications issued in China.
4.2 Where inner vessel is fabricated with pressure strengthening beyond this part, the relevant requirements of TSG 21 shall be implemented.
4.3 The fabrication unit shall fabricate inner vessel in its own unit, verify the adopted welding process and pressure strengthening process and be responsible for the correctness and integrity of process document.
4.4 The fabrication unit shall timely upload the mechanical performance data of product welded test piece and test process data of pressure strengthening to national public service platform for fabricate information about pressure strengthening for cryogenic vessel.
4.5 Special equipment supervision & inspection organization shall supervise and inspect pressure strengthening process adopted for inner vessel and important quality control point proposed by reference to Annex A and shall meet the requirements of this part.
5 Material
5.1 Steel plate
5.1.1 The designation and mechanical performance of steel plate shall meet the requirements specified in Table 1, the supply state shall be in solution heat-treated condition and meet the requirements of GB/T 150.2 and GB/T 24511.
5.1.2 Steel plate shall be re-inspected and at least include the following contents:
a) Check surface quality and material marks of steel plates one by one;
b) Re-inspect room-temperature tensile performance of steel plates by batches;
c) If opened plate is adopted, its re-inspection shall also meet the relevant requirements of GB/T 150.4.
5.1.3 The sampling quantity and position of tensile test shall meet the requirements of GB/T 24511and GB/T 150.2.
5.1.4 The dimension and test method of tensile specimen shall meet the requirements of GB/T 228.1.
Table 1 Mechanical Performance of Steel Plate
Steel grade Room-temperature tension
Stress Rp0.2, where the specified residue elongation is 0.2%/MPa Tensile strength Rm/MPa Elongation after fracture
A/%
S30408 ≥220 520~720 ≥45
S30403 ≥210 490~720
S31608 ≥220 520~720
S31603 ≥210 490~720
5.1.5 Where the tensile strength of steel plate is higher than 720MPa, it shall be subject to welding process qualification again according to 7.4.1 and it may be adopted only after qualification.
5.2 Steel pipe and pipe fittings
5.2.1 Materials for steel pipe and pipe fittings shall meet the requirements of GB/T 18442.2.
5.2.2 Where pipe fittings are processed by adopting cold forming, the measured value of ferrite after forming shall not be greater than 15%.
5.3 Forgings
The stainless steel forgings contacting with medium shall meet the requirements of GB/T 18442.2 and NB/T 47010 and they shall not be inferior to Grade III.
5.4 Welding materials
5.4.1 Welding materials shall meet the corresponding requirements of GB/T 18442.2 and NB/T 47018.1~47018.4.
5.4.2 The chemical composition of deposited metal in welding material for inner vessel shell shall be the same as or close to that of base metal and the strength and toughness of welded joint shall be matched with those of base metal for shell.
5.5 Materials with foreign designations
Where foreign designation is adopted for inner vessel material, it should meet the requirements of Annex B.
5.6 Other materials
Where materials other than those in Table 1 and Table B.1 are adopted for fabrication of inner vessel with pressure strengthening, they shall also meet the relevant requirements of TSG 21.
Foreword i 1 Scope 2 Normative References 3 Terms, Definitions and Symbols 4 General Requirements 5 Material 6 Design 7 Fabrication and Inspection Annex A (Informative) Significant Quality Control Points in Manufacturing Process of Pressure Strengthened Inner Vessel Annex B (Informative) Approximate Comparison and Requirements of Austenitic Stainless Steel Grades Annex C (Informative) Requirements of Pressure Strengthening Process Verification Test Annex D (Informative) Test Piece Pre-tensioning and Test Rules Annex E (Normative) Pressure Strengthening Treatment
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
GB/T 18442 Static Vacuum Insulated Cryogenic Pressure Vessel consists of the following parts under the general title:
——Part 1: General Requirements;
——Part 2: Material;
——Part 3: Design;
——Part 4: Fabrication;
——Part 5: Inspection and Test;
——Part 6: Safety Device Requirements;
——Part 7: Rules of Pressure Strengthening for Inner Vessels.
This part is Part 7 of GB/T 18442.
This part is developed in accordance with the rules given in GB/T 1.1-2009.
This part was proposed by and is under the jurisdiction of National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China (SAC/TC 262).
Static Vacuum Insulated Cryogenic Pressure Vessels
Part 7: Rules of Pressure Strengthening for Inner Vessels
1 Scope
This part of GB/T 18442 specifies the technical requirements for material, design, fabrication and inspection of inner vessel of static vacuum insulated cryogenic pressure vessel fabricated by pressure strengthening (hereafter referred to as inner vessel).
This part is applicable to inner vessel meeting all of the following requirements simultaneously:
a) Meeting the requirements of 1.2, GB/T 18442.1, with contained medium of cryogenic liquefied gas;
b) Its material is austenitic stainless steel;
c) Its nominal thickness is not less than 4mm but not greater than 24mm, and it is composed of single diameter of cylinder and standard ellipsoidal end enclosure;
d) It's subject to pressure strengthening treatment at room temperature.
This part is not applicable to inner vessel filled with medium with moderate or above toxicity hazard degree.
2 Normative References
The following referenced documents are indispensable for the application 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.
GB/T 150 (All parts) Pressure Vessels
GB/T 228.1 Metallic materials - Tensile Testing - Part 1: Method of Test at Room Temperature
GB/T 229 Metallic Materials - Charpy Pendulum Impact Test Method
GB/T 232 Metallic Materials - Bend test
GB/T 2653 Bend Test Methods on Welded Joints
GB/T 3808 Verification of Pendulum-type Impact Testing Machines
GB/T 12160 Calibration of Extensometers Used in Uniaxial Testing
GB/T 14976 Stainless Steel Seamless Tubes for Fluid Transport
GB/T 16825.1 Verification of Static Uniaxial Testing Machines - Part 1: Tension/Compression Testing Machines - Verification and Calibration of the Force-measuring System
GB/T 18442.1~18442.6 Static Vacuum Insulated Cryogenic Pressure Vessel
GB/T 24511 Stainless Steel Plate, Sheet and Strip for Pressure Equipment
NB/T 47010 Stainless and Heat-resisting Steel Forgings for Pressure Equipment
NB/T 47013.2 Nondestructive Testing of Pressure Equipment - Part 2: Radiographic Testing
NB/T 47013.5 Nondestructive Testing of Pressure Equipment - Part 5: Penetrant Testing
NB/T 47013.11 Nondestructive Testing of Pressure Equipment - Part 11: X-ray Digital Radioscopic Testing
NB/T 47014 Welding Procedure Qualification for Pressure Equipment
NB/T 47016 Mechanical Property Tests of Products Welded Test Coupons for Pressure Equipment
NB/T 47018.1 Technical Permission of Welding Materials for Pressure Equipment - Part 1: General Rule
NB/T 47018.2 Technical Permission of Welding Materials for Pressure Equipment - Part 2: Steel Welding Rod
NB/T 47018.3 Technical Permission of Welding Materials for Pressure Equipment - Part 3: Steel Electrodes and Rods for Gas-shielded Arc Welding
NB/T 47018.4 Technical Permission of Welding Materials for Pressure Equipment - Part 4: Electrodes and Fluxes for Submerged Arc Welding
JB 4732-1995 Steel Pressure Vessels - Design by Analysis (Confirmed in 2005)
TSG 21-2016 Supervision Regulation on Safety Technology for Stationary Pressure Vessel
3 Terms, Definitions and Symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 18442.1 and the followings apply.
3.1.1
strengthening pressure
the reached maximum pressure of the top of austenitic stainless steel inner vessel when it's subject to pressure strengthening treatment at room temperature
3.1.2
pressure strengthened vessel
the vessel of which its shell generates overall plastic deformation and reaches structure stability after stopping applying strengthening pressure for the inner vessel made of austenitic stainless steel which is subject to pressure strengthening treatment at room temperature
3.2 Symbol
For the purpose of this document, the following symbols apply.
A——Elongation after fracture, %;
Di——Inside diameter of cylinder or end enclosure, mm;
KV2——Charpy impact absorbed energy, J;
LE——Side expansion value, mm;
pc——Calculated pressure, MPa;
pk——Strengthened pressure, MPa;
Rm——Tensile strength, MPa;
Rp0.2——Stress, where the specified residue elongation of steel is 0.2%, MPa;
δs——Steel thickness, mm;
[σp]t——Permissible stress of cylinder or end enclosure material at the design temperature after pressure strengthening of inner vessel, MPa.
4 General Requirements
4.1 The material, design, fabrication, inspection and identifier of inner vessel shall not only meet the requirements of all parts of this standard, but also comply with the requirements of relevant laws, regulations and safety specifications issued in China.
4.2 Where inner vessel is fabricated with pressure strengthening beyond this part, the relevant requirements of TSG 21 shall be implemented.
4.3 The fabrication unit shall fabricate inner vessel in its own unit, verify the adopted welding process and pressure strengthening process and be responsible for the correctness and integrity of process document.
4.4 The fabrication unit shall timely upload the mechanical performance data of product welded test piece and test process data of pressure strengthening to national public service platform for fabricate information about pressure strengthening for cryogenic vessel.
4.5 Special equipment supervision & inspection organization shall supervise and inspect pressure strengthening process adopted for inner vessel and important quality control point proposed by reference to Annex A and shall meet the requirements of this part.
5 Material
5.1 Steel plate
5.1.1 The designation and mechanical performance of steel plate shall meet the requirements specified in Table 1, the supply state shall be in solution heat-treated condition and meet the requirements of GB/T 150.2 and GB/T 24511.
5.1.2 Steel plate shall be re-inspected and at least include the following contents:
a) Check surface quality and material marks of steel plates one by one;
b) Re-inspect room-temperature tensile performance of steel plates by batches;
c) If opened plate is adopted, its re-inspection shall also meet the relevant requirements of GB/T 150.4.
5.1.3 The sampling quantity and position of tensile test shall meet the requirements of GB/T 24511and GB/T 150.2.
5.1.4 The dimension and test method of tensile specimen shall meet the requirements of GB/T 228.1.
Table 1 Mechanical Performance of Steel Plate
Steel grade Room-temperature tension
Stress Rp0.2, where the specified residue elongation is 0.2%/MPa Tensile strength Rm/MPa Elongation after fracture
A/%
S30408 ≥220 520~720 ≥45
S30403 ≥210 490~720
S31608 ≥220 520~720
S31603 ≥210 490~720
5.1.5 Where the tensile strength of steel plate is higher than 720MPa, it shall be subject to welding process qualification again according to 7.4.1 and it may be adopted only after qualification.
5.2 Steel pipe and pipe fittings
5.2.1 Materials for steel pipe and pipe fittings shall meet the requirements of GB/T 18442.2.
5.2.2 Where pipe fittings are processed by adopting cold forming, the measured value of ferrite after forming shall not be greater than 15%.
5.3 Forgings
The stainless steel forgings contacting with medium shall meet the requirements of GB/T 18442.2 and NB/T 47010 and they shall not be inferior to Grade III.
5.4 Welding materials
5.4.1 Welding materials shall meet the corresponding requirements of GB/T 18442.2 and NB/T 47018.1~47018.4.
5.4.2 The chemical composition of deposited metal in welding material for inner vessel shell shall be the same as or close to that of base metal and the strength and toughness of welded joint shall be matched with those of base metal for shell.
5.5 Materials with foreign designations
Where foreign designation is adopted for inner vessel material, it should meet the requirements of Annex B.
5.6 Other materials
Where materials other than those in Table 1 and Table B.1 are adopted for fabrication of inner vessel with pressure strengthening, they shall also meet the relevant requirements of TSG 21.
Contents of GB/T 18442.7-2017
Foreword i
1 Scope
2 Normative References
3 Terms, Definitions and Symbols
4 General Requirements
5 Material
6 Design
7 Fabrication and Inspection
Annex A (Informative) Significant Quality Control Points in Manufacturing Process of Pressure Strengthened Inner Vessel
Annex B (Informative) Approximate Comparison and Requirements of Austenitic Stainless Steel Grades
Annex C (Informative) Requirements of Pressure Strengthening Process Verification Test
Annex D (Informative) Test Piece Pre-tensioning and Test Rules
Annex E (Normative) Pressure Strengthening Treatment
