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GB/T 12777-2019 English PDF

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GB/T 12777-2019: General specification for metal bellows expansion joints
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GB/T 12777: Evolution and historical versions

Standard IDContents [version]USDSTEP2[PDF] delivered inStandard Title (Description)StatusPDF
GB/T 12777-2019English2139 Add to Cart 11 days [Need to translate] General specification for metal bellows expansion joints Valid GB/T 12777-2019
GB/T 12777-2008EnglishRFQ ASK 8 days [Need to translate] General specification for metal bellows expansion joints Obsolete GB/T 12777-2008
GB/T 12777-1999EnglishRFQ ASK 9 days [Need to translate] General specification for metal bellows expansion joints Obsolete GB/T 12777-1999
GB/T 12777-1991EnglishRFQ ASK 3 days [Need to translate] General specification of metallic bellows expansion joints Obsolete GB/T 12777-1991

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Basic data

Standard ID GB/T 12777-2019 (GB/T12777-2019)
Description (Translated English) General specification for metal bellows expansion joints
Sector / Industry National Standard (Recommended)
Classification of Chinese Standard U50
Classification of International Standard 47.020.30
Word Count Estimation 107,175
Date of Issue 2019-05-10
Date of Implementation 2019-12-01
Issuing agency(ies) State Administration for Market Regulation, China National Standardization Administration

GB/T 12777-2019: General specification for metal bellows expansion joints

---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
General specification for metal bellows expansion joints ICS 47.020.30 U50 National Standards of People's Republic of China Replace GB/T 12777-2008 General technical requirements for metal bellows expansion joints 2019-05-10 released 2019-12-01 implementation State Administration for Market Regulation Issued by China National Standardization Administration

Table of contents

Preface Ⅲ 1 Scope 1 2 Normative references 1 3 Terms and definitions 2 4 Classification and marking 4 4.1 Classification 4 4.2 Model and marking 16 5 Material 16 5.1 Bellows 16 5.2 Pressure parts 17 5.3 Force parts 17 5.4 Allowable stress 18 5.5 Material inspection 18 6 Dimensions and deviations 18 6.1 Round bellows 18 6.2 Rectangular bellows 19 6.3 Pressure cylinder section 19 6.4 Expansion joint 19 6.5 Inspection of dimensions and deviations 19 7 Design 20 7.1 Design conditions 20 7.2 Welded joint coefficient 23 7.3 Bellows 23 7.4 Structural parts 23 7.5 Guide tube 23 7.6 Shipping fixture 23 7.7 Protective cover 23 7.8 Expansion joint 24 8 Manufacturing 24 8.1 Material mark transplantation 24 8.2 Round bellows 24 8.3 Rectangular bellows 24 8.4 Pressure cylinder section 24 8.5 Welding 24 8.6 Expansion joint 25 9 Inspection and testing 25 9.1 Requirements for appearance inspection 25 9.2 Visual inspection method 26 9.3 Requirements for non-destructive testing of welded joints 26 9.4 Non-destructive testing methods for welded joints 27 9.5 Test requirements 28 9.6 Test method 29 10 Inspection rules 31 10.1 Inspection classification 31 10.2 Type inspection 31 10.3 Factory inspection 32 11 Sign 33 11.1 Nameplate 33 11.2 Medium flow direction mark 33 11.3 Shipping fixture marking 33 12 Packaging, transportation and storage 33 12.1 Packaging and transportation 33 12.2 Storage 33 13 Selection 33 14 Installation and use requirements 34 15 Safety Recommendations 34 Appendix A (Normative Appendix) Design of Circular Bellows 35 Appendix B (informative appendix) Design of rectangular bellows 61 Appendix C (informative appendix) Design of structural parts 67 Appendix D (informative appendix) High temperature fatigue test of bellows 77 Appendix E (informative appendix) Selection 81 Appendix F (informative appendix) Installation and use requirements 94 Appendix G (informative appendix) Safety recommendations 96 Appendix H (informative appendix) Fatigue design method for bellows of other materials 99 References 101

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009. This standard replaces GB/T 12777-2008 "General Technical Requirements for Metal Bellows Expansion Joints". This standard and GB/T 12777- Compared with.2008, the main technical changes are as follows. ---Modified the scope of application of the standard (see Chapter 1, Chapter 1 of the.2008 edition); ---Modified the normative references (see Chapter 2, Chapter 2 of the.2008 edition); ---Modified terms and definitions (see Chapter 3, Chapter 3 of the.2008 edition); ---Modified the classification of expansion joints (see 4.1.1, 4.1.1 of the.2008 edition); ---Modified the type classification of expansion joints (see 4.1.2, 4.1.2 of the.2008 edition); ---The classification of expansion joints according to restraint pressure thrust has been added (see 4.1.2); ---The component classification of expansion joints has been added (see 4.1.3); ---Added welding joint classification, welding joint coefficient and welding requirements (see 4.1.4, 7.2 and 8.5); ---Modified the model representation method and marking examples (see 4.2.1 and 4.2.2, 4.2.1 and 4.2.2 of the.2008 edition); ---Modified the commonly used bellows material grades (see 5.1.1, 5.1.1 in the.2008 edition); ---Added a multi-layer corrugated pipe that can use different materials for each layer (see 5.1.2); ---The calculation method of allowable stress for multi-layer bellows with different material combinations has been added (see 5.4.3); ---Modified the specific requirements for the limit deviation of the bellows size (see 6.1.1, 6.1.3, 6.1.5 and 6.1.6, 5.6.1.1,.2008 edition 5.6.1.2, 5.6.1.4 and 5.6.1.5); ---The wave height consistency requirement of the bellows has been added (see 6.1.2); ---Modified the butt groove form of the end pipe welding end (see 6.3.2, 5.6.3.2 of the.2008 edition); ---The design conditions of bellows expansion joints have been added (see 7.1); ---Added material mark transplantation requirements (see 8.1); ---Modified the requirements and methods of non-destructive testing (see 9.3 and 9.4, 5.5 and 6.3 of the.2008 edition); ---Added the penetration test requirements for the welded joints after the bellows is formed (see 9.3.2.4); ---Modified the pressure, air tightness and fatigue performance test requirements and test methods (see 9.5.1, 9.5.2, 9.5.5, 9.6.1, 9.6.2 and 9.6.5, 5.7, 5.8, 5.9, 6.5, 6.6 and 6.7 of the.2008 edition); --- Deleted the kerosene leakage test (see 6.6.2 of the.2008 edition); ---Added stiffness, stability and blasting performance test requirements and test methods (see 9.5.3, 9.5.4, 9.5.6, 9.6.3, 9.6.4 and 9.6.6); ---Modified the items and sequence of type inspection and factory inspection (see 10.2.2 and 10.3.1, 7.2.2 and 7.3.1 of the.2008 edition); ---Modified the number of samples for type inspection (see 10.2.3, 7.2.3 of the.2008 edition); --- Modified the type inspection and factory inspection judgment rules (see 10.2.4 and 10.3.3, 7.2.4 and 7.3.3 of the.2008 edition); ---Modified the nameplate content (see 11.1, 8.1 in.2008 edition); ---Modified the calculation formula of circular bellows design (see Appendix A, Appendix A of the.2008 edition); --- Increase the strength calculation and evaluation method of external pressure bellows (see A.2.6.1 and A.2.6.2); ---Added the calculation method of the cumulative fatigue life of the bellows (see A.2.7); ---Modified the design and calculation method of the guide tube (see A.5,.2008 edition of A.5); ---Added the calculation method of protective cover design (see A.6); ---Modified the calculation formula for the rectangular bellows design (see Appendix B, Appendix B of the.2008 edition); --- Added general requirements for structural design (see C.2); ---Modified the design calculation formula of the circular universal ring (see C.8.1, C.7.1 of the.2008 edition); ---The high temperature fatigue test of the bellows has been added (see Appendix D); ---Added the selection (see Appendix E); ---Added installation and use requirements (see Appendix F); ---Added safety recommendations (see Appendix G); ---Added fatigue design methods for bellows of other materials (see Appendix H). This standard was proposed and managed by the National Marine Machinery Standardization Technical Committee (SAC/TC137). Drafting organizations of this standard. the 725th Research Institute of China Shipbuilding Industry Corporation, Luoyang Shuangrui Special Equipment Co., Ltd., Nanjing Chenguang Dongluo Bellows Co., Ltd., Sinopec Engineering Construction Co., Ltd., China State Shipbuilding Industry Technical and Economic Research Institute, Hudong Zhonghua Shipbuilding (Group) Co., Ltd., the 719th Research Institute of China Shipbuilding Industry Corporation, China Huanqiu Engineering Co., Ltd. Beijing Branch, Sinopec Luoyang Engineering Co., Ltd., China Municipal Engineering North China Design and Research Institute Co., Ltd., Beijing Gas and Thermal Engineering Design Institute Co., Ltd. The main drafters of this standard. Zhong Yuping, Zhang Xiaowen, Liu Yan, Zhang Aiqin, Zhang Daowei, Niu Yuhua, Zhao Sizhen, Zhang Meiling, Geng Haiping, Hu Zhimin, Zhang Shichen, Li Zhongyang, Gong Yucai, Yang Liangzhong, Sun Lei. The previous versions of the standard replaced by this standard are as follows. ---GB/T 12777-1991, GB/T 12777-1999, GB/T 12777-2008. General technical requirements for metal bellows expansion joints

1 Scope

This standard specifies the terms and definitions, classification and marking, materials, dimensions and deviations of metal bellows expansion joints (hereinafter referred to as "expansion joints") Poor, design, manufacture, inspection and testing, inspection rules, marking, packaging, transportation and storage, selection, installation and use requirements and safety recommendations. This standard applies to the design, manufacture, inspection, selection, installation and use of expansion joints installed in pipelines whose flexible elements are metal bellows. The expansion joints in other occasions can be used as reference.

2 Normative references

The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this article Pieces. For undated references, the latest version (including all amendments) applies to this document. GB/T 150.3-2011 Pressure Vessel Part 3.Design GB/T 1800.1-2009 Geometric Technical Specifications for Products (GPS) Limits and Fits Part 1.Basis of Tolerances, Deviations and Fits GB/T 2059 Copper and copper alloy strip GB/T 3280 Cold rolled stainless steel plate and strip GB/T 3621 Titanium and titanium alloy sheet GB/T 4237 stainless steel hot-rolled steel plate and strip GB/T 8163 Seamless steel pipe for conveying fluid GB/T 9711 Steel Pipe for Pipeline Transportation System of Petroleum and Natural Gas Industry GB/T 12771 Stainless steel welded steel pipe for conveying fluid GB/T 14976 Seamless stainless steel pipe for fluid transportation GB/T 20801.2 Pressure Piping Specification Industrial Piping Part 2.Materials GB/T 20801.4-2006 Pressure Piping Specification Industrial Piping Part 4.Fabrication and Installation GB/T 24511 Stainless steel and heat-resistant steel plates and strips for pressure equipment GB 50235-2010 Construction Code for Industrial Metal Pipeline Engineering JB/T 4711 Pressure vessel coating and transportation packaging NB/T 47008 Carbon steel and alloy steel forgings for pressure equipment NB/T 47010 stainless steel and heat-resistant steel forgings for pressure equipment NB/T 47013.2-2015 Non-destructive testing of pressure equipment Part 2.Radiographic testing NB/T 47013.3-2015 Non-destructive testing of pressure equipment Part 3.Ultrasonic testing NB/T 47013.5-2015 Pressure equipment non-destructive testing Part 5.Penetration testing NB/T 47013.10-2015 Pressure-bearing equipment non-destructive testing Part 10.Ultrasonic testing by diffraction time difference method NB/T 47013.11-2015 Non-destructive testing of pressure equipment Part 11.X-ray digital imaging testing NB/T 47013.14-2016 Non-destructive testing of pressure equipment Part 14.X-ray computer-aided imaging testing NB/T 47014 welding procedure qualification for pressure equipment NB/T 47018 Ordering technical conditions of welding materials for pressure equipment YB/T 5354 Corrosion resistant alloy cold rolled sheet

3 Terms and definitions

The following terms and definitions apply to this document. 3.1 Bellows expansion joint Composed of one or several corrugated pipes and structural parts, used to absorb the dimensional changes of pipes and (or) equipment caused by thermal expansion and contraction. 3.2 Round bellows In the expansion joint, a circular flexible element composed of one or more circular corrugations and straight end sections. For reinforced U-shaped bellows and Ω Shaped bellows, including strengthening ring and equalizing ring. 3.3 Rectangular bellows In the expansion joint, a rectangular flexible element composed of one or more rectangular corrugations and straight end sections. 3.4 Single axial expansion joint Composed of a bellows and structural parts, it is mainly used for the expansion joints that absorb axial displacement and cannot bear the pressure thrust of the bellows. 3.5 External pressure axial expansion joint Composed of structural parts such as bellows that bear external pressure, outer pipes and end rings, which are mainly used to absorb axial displacement and cannot bear the pressure of bellows Expansion joints for thrust.

4 Classification and marking

4.1 Classification 4.1.1 Classification of expansion joints Expansion joints are divided into three types according to working conditions, see Table 1. 4.1.2 Type classification of expansion joints Expansion joints can be divided into two types. unconstrained and constrained according to whether they can constrain the pressure and thrust. Commonly used expansion joints are divided into 15 types according to the structural form Type, see Table 2. 4.1.3 Classification of expansion joints 4.1.3.1 Components of expansion joints The expansion joint is composed of bellows and structural parts. The structural parts are divided into pressure parts, stressed parts and non-pressure (force) parts. 4.1.3.2 Bellows (P0) The failure of components (including strengthening ring, equalizing ring and strengthening ring) that play the role of displacement compensation will lead to the loss of the function of the expansion joint, see Figure 16. 4.1.3.3 Pressure parts (P1) The failure of components directly in contact with the pressurized medium will cause the pressure to be released suddenly, see Figure 16. 4.1.3.4 Force parts (P2) The failure of components that bear the pressure and thrust of the bellows (such as hinge plates, tie rods, etc.) will cause the loss of the restraint function of the expansion joint, see Figure 16. 4.1.3.5 Non-compression (force) parts (P3, P4) Non-compression (force) parts are divided into P3 and P4 (see Figure 16). a) Parts connected with pressure parts or stress parts (P3); b) Components other than P3 components (P4). a) Single axial type b) External pressure axial type c) Single hinge type d) Double lever type a If it is a reinforced collar, it is P0. 4.1.4 Classification of welded joints 4.1.4.1 The welded joints of bellows, pressure parts, and stress parts in expansion joints are divided into the following four categories (see Figure 17). a) Corrugated pipe longitudinal butt joints (including strengthening ring, equalizing ring and strengthening collar), compression tube section (including connecting pipe and end pipe) longitudinally aligned All longitudinal tailor-welded joints and end ring-type tailor-welded joints are classified as Class A welded joints; b) The circumferential joint of the bellows and the pressure cylinder section and the circumferential butt joint of the pressure cylinder section are all Type B welded joints; c) Flat flanges, end plates, end rings, vertical plates, etc. are connected to the pressure cylinder section, and the reinforcement collar, end balance ring and the pressure cylinder section are connected Lap joints are all Type C welded joints; d) The joints between the pressure cylinder section and the head, the joints between the detection tube and the straight side section of the corrugated pipe, are all D-type welded joints. 4.1.4.2 Other welded joints are Class E welded joints, see Figure 17. 4.1.5 Type classification of bellows The type and code of the bellows in the expansion joint are shown in Table 3. 4.1.6 Classification of end connection types The connection type and code of the end of the expansion joint and the pipeline or equipment are shown in Table 4. 4.2 Model and marking 4.2.1 Model representation method Expansion joint model representation method is as follows. Expansion joint type code (see Table 2). Bellows type code (see Table 3); Type code of the end of the expansion joint (see Table 4); The value of 10 times the design pressure, in megapascals (MPa); The value of the nominal size. the round pipe is the nominal diameter, and the unit is millimeters (mm); Rectangular pipe is long side × short side, the unit is millimeter (mm); The value of the design displacement in millimeters (mm) or degrees (°); Note. For expansion joints with combined displacements (codes FZ, FZB, WP, FJP, FWP, etc.), the design displacement represents the design axial displacement and the design transverse position respectively. When the displacement is moved, the axial displacement is in the front and the lateral displacement is in the back. The displacements are connected with a "/".

5 materials

5.1 Bellows 5.1.1 The material of the bellows should be selected according to the working conditions such as working medium, external environment and working temperature. Commonly used bellows materials are shown in Table 5. 5.1.2 Different materials can be used for each layer of the multi-layer corrugated pipe. 5.1.3 Refer to GB/T 20801.2, GB/T 24511, NB/T 47008, NB/T 47010 for commonly used materials for strengthening ring or equalizing ring. 5.2 Pressure parts The material used for pressure parts such as the middle end pipe and flange of the expansion joint should be the same as or better than that of the pipe in the pipeline where the expansion joint is installed. Commonly used pressure parts materials see GB/T 20801.2, GB/T 24511, NB/T 47008, NB/T 47010. 5.3 Force parts The tension rods, hinge plates, universal rings, pin shafts and their connecting accessories in the expansion joints should be used in accordance with the pressure and thrust of the bellows. Selection of working conditions. 5.4 Allowable stress 5.4.1 The allowable stress shall comply with the relevant material standards. 5.4.2 When the design temperature is lower than 20℃, the allowable stress of 20℃ shall be taken. 5.4.3 The allowable stress at the design temperature of multi-layer bellows with different material combinations is calculated according to formula (1). 5.5 Material inspection Use the method of checking the material designation, appearance quality and quality certificate to carry out material inspection, and the results should meet the requirements of 5.1, 5.2 and 5.3.

6 Dimensions and deviations

6.1 Round bellows 6.1.1 The limit deviation of the wave height and wave distance of the U-shaped bellows should be implemented in accordance with Table 6, and the limit deviation of the corrugated length should be implemented in accordance with Table 7. 6.1.2 The consistency requirements of the wave height in the same U-shaped corrugated pipe shall be implemented in accordance with Table 8. 6.1.4 The limit deviation of the radius of curvature of the peak and valley of the U-shaped bellows shall be ±15% of the nominal radius of curvature of the ripple, and the peak, valley and wave side The transition between the walls should be smooth. 6.1.5 The limit deviation of the average corrugation radius of the Ω-shaped bellows should be ±15% of the nominal average radius of the corrugation, and the roundness of the Ω-shaped corrugated section The difference should be ±20% of the nominal average radius of the corrugation. 6.1.6 The perpendicularity tolerance of both ends of the bellows facing the axis of the bellows should be 1% of the outer diameter of the straight side section of the bellows, and not more than 3mm. Straight edge For corrugated pipes with a section outer diameter not greater than.200mm, the coaxiality tolerance between the axis of the two ends of the bellows and the axis of the bellows shall be ϕ2mm; straight side section For bellows with an outer diameter greater than.200mm, the coaxiality tolerance between the two ends of the bellows and the axis of the bellows should be 1%. The outer diameter is not greater than ϕ5mm. 6.2 Rectangular bellows 6.2.1 The requirements of corrugated pipe wave height, wave distance and corrugation length shall be in accordance with the provisions in 6.1.1. 6.2.2 The standard tolerance level of the side length and diagonal of the bellows shall be IT17 level in Table 1 of GB/T 1800.1-2009, and its limit deviation It is ±IT17/2, and not more than 8mm. 6.3 Pressure cylinder section 6.3.1 The size of the rolled circular pressure cylinder section shall meet the requirements of 5.4 in GB 50235-2010. 6.3.2 See Figure 18 for the butt groove of the end pipe welded connection end connected to the pipeline or equipment. When the wall thickness of the end pipe is greater than the wall thickness of the connected pipe, press The requirements of 7.4.3a) in GB/T 20801.4-2006 are thinned. a) End pipe wall thickness≤20mm b) End pipe wall thickness >20mm Figure 18 End pipe welding connection end butt groove form 6.3.3 The standard tolerance grade of the side length and diagonal of the rectangular pressure cylinder shall meet the requirements of 6.2.2. 6.4 Expansion joint See Table 10 for the limit deviation of the dimensions between the outer connecting end faces of the expansion joint. 6.5 Inspection of dimensions and deviations The inspection of dimensions and deviations should be carried out with a measuring tool or measuring instrument whose accuracy meets the tolerance requirements and has been verified. The results should meet 6.1, 6.2, The requirements of 6.3 and 6.4.

7 Design

7.1 Design conditions 7.1.1 The system design unit or user should provide the design conditions of expansion joints in accordance with Table 11 or Table 12.The design pressure and design Measure temperature, design displacement and design fatigue life. The torsion of the bellows should be avoided. When the torsion of the circular bellows is unavoidable, it should be Torque on expansion joints. 7.1.2 The design pressure of the expansion joint should not be lower than the maximum working pressure given in Table 11 or Table 12, and should not be higher than 1.1 of the maximum working pressure. Times. When determining the design pressure, the piping test pressure should be taken into account. 7.1.3 When the expansion joint bears internal pressure and external pressure at the same time, or operates under vacuum conditions, the design pressure should take into account the The maximum internal and external pressure difference that can occur. 7.1.4 For expansion joints without internal heat insulation structure, the design temperature of the bellows should be based on the working temperature; for expansion joints with heat insulation structure, the bellows The design temperature of the tube should be determined according to heat transfer analysis calculations, tests or with reference to the actual temperature measured under the operating conditions of similar devices. 7.1.5 When determining the design temperature, various conditions including the low temperature conditions of the atmospheric environment expected during the operation of the expansion joint should be taken into account. 7.1.6 Refer to Appendix C C.2.3 for the determination of the design temperature of the expansion joint structure. 7.4 Structural parts Refer to Appendix C for the design of structural parts such as pressure parts and stress parts in expansion joints. 7.5 Guide tube 7.5.1 The design of the expansion joint diversion tube is shown in Appendix A, A.5. 7.5.2 When the temperature of the working medium is higher than the upper limit of the allowable temperature of the bellows material, it should be in the annular space between the diversion tube and the bellows Fill with heat-insulating material compatible with the temperature and characteristics of the working medium. The heat-insulating material should be reliably fixed to the diversion tube or end pipe. 7.5.3 When the working medium contains dust, a dust-proof device should be installed at the open end of the diversion tube, and the dust-proof device should be reliably fixed with the diversion tube or end pipe. And the open end of the guide tube should not be upward. 7.5.4 When the working medium is liquid or steam and flows upward, the deflector should be provided with a drain hole. 7.6 Shipping fixtures 7.6.1 Expansion joints should be provided with shipping fixtures to keep the expansion joints at the correct length during transportation and installation. After the expansion joint is installed The shipping fasteners should be removed or loosened before the system pressure test. When pre-shifting is required during installation, the shipping fasteners should be removed before pre-shifting. 7.6.2 When the mass of the expansion joint is greater than.200kg, a lifting device should be installed. 7.7 Protective cover The design of the expansion joint protective cover is shown in Appendix A, A.6. 7.8 Expansion joint The connection type of the straight side section of the bellows and the pressure cylinder section (flange) in the expansion joint should adopt an insert or outer sleeve structure.

8 Manufacturing

8.1 Material mark transplantation 8.1.1 The materials of bellows (P0), pressure parts (P1) and stress parts (P2) shall have traceable marks. In the manufacturing process, if the original logo is When cut...

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