NB/T 47058-2017Road tankers for refrigerated liquefied gas (English PDF)

Foreword

This document was issued on 15 November 2017 by the National Energy Administration of the PRC and takes effect on 1 March 2018.

It is a NB/T standard: recommended rather than compulsory, but it is the text a Chinese reviewer applies when assessing a submission.

It is classified under ICS 43.160, Chinese classification T58.

It replaces JB/T 4783-2007, which is superseded.

This standard was drafted in accordance with the rules given in GB/T 1.1-2009 Directives for standardization — Part 1: Structure and drafting of standards.

This standard replaces JB/T 4783-2007 Cryogenic liquid road tankers. Compared with JB/T 4783-2007, the main technical changes are as follows.

a) Title of the standard: changed from 'Cryogenic liquid road tankers' to 'Road tankers for refrigerated liquefied gas'.

b) Scope: added the exclusions from the scope, the delimitation of the scope of the tanker and of the tank, and the definition of the main pressure-bearing components.

c) Terms and definitions: deleted 19 terms and definitions such as cryogenic liquid and insulation layer; revised and added 11 terms and definitions such as high vacuum multilayer insulation and refrigerated liquefied gas.

d) Qualification and responsibilities: the original 'Responsibilities' was changed to 'Qualification and responsibilities'; the responsibilities of the user or the party commissioning the design were added, and the requirements on the responsibilities of the design and manufacturing units were modified and improved.

e) Materials: modified the requirements for steel plates, steel forgings, steel pipes and pipe fittings, welding materials, insulation materials, adsorbent materials and interlayer support materials of the tank; added requirements for sealing gasket materials.

f) Design: modified the design requirements for the complete vehicle, loads, design temperature, design pressure, piping etc., and added requirements for the design-by-analysis method, minimum design metal temperature, minimum thickness of the tank, maximum permissible filling quantity etc.

g) Safety accessories, instruments and loading/unloading accessories: explicitly listed the types of safety accessories, instruments and loading/unloading accessories, and modified the related technical requirements.

h) Manufacture: modified the requirements for classification of welded joints, re-inspection of materials, cold and hot forming, assembly, welding and non-destructive testing, and added requirements for category E welded joints and coating of the tank.

i) Test methods: added test methods such as the ammonia leak test, the halogen leak test and the helium leak test.

j) Inspection rules: modified the requirements of the inspection rules and added a table of inspection items and technical requirements.

k) Marking and identification: modified the specific requirements for marking and identification.

l) Annexes: added the two annexes 'Declaration of conformity and revision of the standard' and 'Risk assessment report'; deleted the three original annexes 'Format and content of product nameplate', 'Format and content of product quality certificate' and 'Physical property parameters of common cryogenic liquids'.

The original Annex A 'Design calculation of safety relief devices' was changed to Annex C 'Calculation of safety relief rate of the tank and discharge capacity of overpressure relief devices', and the content of the calculation of the safety relief rate of the tank and of the discharge capacity of overpressure relief devices was modified.

This standard was proposed by and is under the jurisdiction of the National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China (SAC/TC 262).

Attention is drawn to the possibility that some of the elements of this document may be the subject of patents. The issuing body of this document shall not be held responsible for identifying any or all such patents.

The drafting of this standard was organized by the Subcommittee on Mobile Pressure Vessels of the National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China (SAC/TC 262/SC4).

Drafting organizations of this standard: Zhangjiagang CIMC Sanctum Cryogenic Equipment Co., Ltd., Shanghai Gas Industry Association, China Special Equipment Inspection and Research Institute, Shanghai Huayi Group Equipment Engineering Co., Ltd., Jiangsu Province Special Equipment Safety Supervision and Inspection Institute Zhangjiagang Branch, Chate Zhongqi Shenleng Tezhongche (Changzhou) Co., Ltd., Nantong CIMC Energy Equipment Co., Ltd., Zhangjiagang Hanzhong Shenleng Technology Co., Ltd., Jiangxi Zhiyangji Co., Ltd., Jingmen Hongtu Special Aircraft Manufacturing Co., Ltd., Shanghai Institute of Special Equipment Supervision and Inspection Technology, Aerosun Corporation, Changzhou Bolang Cryogenic Equipment Co., Ltd., Beijing Jianan Texiweiou Special Equipment Manufacturing Co., Ltd., Tieling Huanghai Special Vehicle Manufacturing Co., Ltd.

Chief drafters of this standard: Gao Jie, Zhou Weiming, Luo Xiaozhong, Teng Junhua, Chen Chaohui, Wang Fei, He Hua, Chen Wenfeng, Jiang Ping'an, Yin Jinsong, Chen Yanshan, Xiao Xuewen, Ding Jianxun, Wang Fang, Zhu Yanmei, Ye Yanyuan, Chen Liyan.

The previous edition of the standard replaced by this standard is JB/T 4783-2007.

1 Scope

NB/T 47058-2017 governs road tankers for refrigerated liquefied gas, replacing JB/T 4783-2007. These are the truck-mounted and semi-trailer tanks that deliver liquid nitrogen, oxygen, argon, carbon dioxide and LNG by road: an inner vessel at cryogenic temperature inside an outer jacket, with the space between evacuated and filled with powder or multilayer insulation. The standard applies to inner vessels with a design pressure of at least 0.1 MPa and a volume of at least one cubic metre. It sets the scope, some seventy normative references and a full set of defined terms, then the qualification and responsibilities of the designer, manufacturer and inspection body. Materials are specified for the inner vessel, the outer jacket, the supports and the insulation, with the low-temperature toughness required and the tables of permitted grades and properties. Design follows: the inner vessel for internal pressure and the loads of road transport, the outer jacket against external pressure from the vacuum, the supports that carry the inner vessel with minimum heat leak, the connection to the vehicle chassis, the insulation and vacuum system, and the sizing of piping, valves, pressure relief devices and level and pressure instruments. Fabrication and welding, non-destructive examination, pressure and leak tests, the vacuum and evaporation rate tests that prove the insulation, marking and the delivery documentation complete the standard.

1.1 This standard specifies the requirements for materials, design, manufacture, test methods, inspection rules, marking and identification, delivery documents, storage and transportation of road tankers for refrigerated liquefied gas (hereinafter referred to as tankers).

1.2 This standard is applicable to tankers whose tank inner vessel has a design pressure not less than 0.1 MPa and a geometric volume not less than 1 cubic metre, which adopt vacuum powder insulation or high vacuum multilayer insulation, and whose tank is permanently connected to a type-approved chassis or a semi-trailer running gear.

1.3 This standard is not applicable to the following tankers: a) tanks made of non-ferrous metals or non-metallic materials; b) tankers filled with refrigerated liquefied gas media whose normal boiling point is lower than minus 196 degrees Celsius; c) tankers filled with toxic media; d) national defence and military equipment and other tankers with special requirements.

1.4.1 The tanker to which this standard applies includes the tank, piping, safety accessories, instruments, loading/unloading accessories, and the type-approved chassis or semi-trailer running gear, supports, operating cabinet, self-pressurizer etc.

1.4.2 The scope of the tank is delimited as follows: a) the groove end face of the first circumferential joint where the tank is welded to the piping; b) the end face of the first threaded joint where the tank is connected by thread to piping or safety accessories, and the first flange sealing face for flanged connections; c) the covers of tank openings and their fasteners; d) the welds connecting the tank to non-pressure components.

1.4.3 The piping includes all pipes and pipe fittings connected to the tank.

1.4.4 The main pressure-bearing components include the shell and heads of the inner vessel, and the pipes, nozzles, flanges and flange covers with a nominal diameter not less than 15 mm in contact with the filled medium.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including all amendments) applies.

GB/T 150.1 Pressure vessels — Part 1: General requirements

GB/T 150.2 Pressure vessels — Part 2: Materials

GB/T 150.3-2011 Pressure vessels — Part 3: Design

GB/T 150.4-2011 Pressure vessels — Part 4: Fabrication, inspection and testing, and acceptance

GB/T 567.1 Bursting disc safety devices — Part 1: Basic requirements

GB/T 567.2 Bursting disc safety devices — Part 2: Application, selection and installation

GB/T 567.3 Bursting disc safety devices — Part 3: Classification and installation dimensions

GB/T 713 Steel plates for boilers and pressure vessels

GB 1589 Limits of dimensions, axle load and masses for motor vehicles, trailers and combination vehicles

GB/T 1804-2000 General tolerances — Tolerances for linear and angular dimensions without individual tolerance indications

GB/T 3531 Low alloy steel plates for low temperature pressure vessels

GB/T 3730.2 Road vehicles — Masses — Vocabulary and codes

GB/T 3730.3 Terms and definitions of motor vehicles and trailers — Vehicle dimensions

GB/T 4351 (all parts) Portable fire extinguishers

GB/T 4606 Road vehicles — Semi-trailer fifth wheel coupling pin 50 — Basic dimensions for mounting and interchangeability

GB/T 4607 Road vehicles — Semi-trailer fifth wheel coupling pin 90 — Basic dimensions for mounting and interchangeability

GB 4785 Prescription for installation of the external lighting and light-signalling devices for motor vehicles and their trailers

GB 7258 Technical specifications for safety of power-driven vehicles operating on roads

GB/T 9969 General principles for preparation of instructions for use of industrial products

GB 11567 Motor vehicles and trailers — Lateral and rear underrun protection requirements

GB/T 12241 Safety valves — General requirements

GB/T 12243 Spring loaded safety valves

GB 12676 Technical requirements and testing methods for commercial vehicle and trailer braking systems

GB/T 13296 Seamless stainless steel tubes for boilers and heat exchangers

GB 13365 Spark arresters for motor vehicle exhaust

GB 13392 Marks for road transport vehicles of dangerous goods

GB/T 13550 5A molecular sieve and its testing methods

GB/T 13881 Connectors for air brake lines between tractors and trailers

GB/T 14525 General specification for corrugated metal hoses

GB/T 14976 Seamless stainless steel pipes for fluid transport

GB 16735 Road vehicles — Vehicle identification number (VIN)

GB/T 17600 (all parts) Steel — Conversion of elongation values

GB/T 18443 (all parts) Testing method of performance for vacuum insulation cryogenic equipment

GB/T 20070 Road vehicles — Mechanical coupling between tractors and semi-trailers — Interchangeability

GB 20300 Safety specifications for road vehicles transporting explosives and highly toxic chemicals

GB 21668 Structural requirements for vehicles transporting dangerous goods

GB/T 23336 General specification of semi-trailers

GB/T 24511 Stainless steel plate, sheet and strip for pressure equipment

GB/T 24918 Emergency shut-off valves for cryogenic media

GB/T 25198 Heads for pressure vessels

GB/T 26929 Terminology for pressure vessels

GB/T 31480 High vacuum multilayer insulation materials for cryogenic vessels

GB/T 31481 Guide for compatibility judgement of materials and gases for cryogenic vessels

NB/T 47009 Low alloy steel forgings for low temperature pressure equipment

NB/T 47010 Stainless and heat-resisting steel forgings for pressure equipment

NB/T 47013.1 Nondestructive testing of pressure equipment — Part 1: General requirements

NB/T 47013.2 Nondestructive testing of pressure equipment — Part 2: Radiographic testing

NB/T 47013.3 Nondestructive testing of pressure equipment — Part 3: Ultrasonic testing

NB/T 47013.4 Nondestructive testing of pressure equipment — Part 4: Magnetic particle testing

NB/T 47013.5 Nondestructive testing of pressure equipment — Part 5: Penetrant testing

NB/T 47013.10 Nondestructive testing of pressure equipment — Part 10: Ultrasonic time of flight diffraction technique

NB/T 47013.11 Nondestructive testing of pressure equipment — Part 11: X-ray digital radiography testing

NB/T 47013.14 Nondestructive testing of pressure equipment — Part 14: X-ray computer aided radiography testing

NB/T 47014 Welding procedure qualification for pressure equipment

NB/T 47016 Mechanical property tests of product welded test coupons for pressure equipment

NB/T 47018.1 Technical ordering conditions of welding materials for pressure equipment — Part 1: General rules for purchasing

NB/T 47018.2 Technical ordering conditions of welding materials for pressure equipment — Part 2: Steel electrodes

NB/T 47018.3 Technical ordering conditions of welding materials for pressure equipment — Part 3: Steel welding wires and filler rods for gas shielded arc welding

NB/T 47018.4 Technical ordering conditions of welding materials for pressure equipment — Part 4: Steel welding wires and fluxes for submerged arc welding

HG/T 2690 13X molecular sieve

JB/T 4711 Coating and packing for transportation of pressure vessels

JB 4732-1995 Steel pressure vessels — Design by analysis (confirmed in 2005)

JB/T 5943 General technical specification for weldments of construction machinery

JB/T 6804 Shock-resistant pressure gauges

JB/T 6896 Surface cleanliness of air separation equipment

JT 230 Anti-static rubber earthing straps for automobiles

QC/T 252 Type test procedures for special purpose vehicles

QC/T 310 Landing gear (support devices) for semi-trailers

QC/T 484 Paint coatings for automobiles

YS/T 599 Ultrafine palladium oxide powder

TSG R0005 Supervision regulation on safety technology for mobile pressure vessels

TSG Z6002 Rules for examination of welding operators of special equipment

3 Terms and definitions

For the purposes of this document, the terms and definitions given in GB/T 150.1, GB/T 150.4, GB/T 3730.2, GB/T 3730.3, GB/T 18443 and GB/T 26929 and the following apply.

3.1 refrigerated liquefied gas: gas which is partially liquid during transport because of its low temperature, with a critical temperature generally not higher than minus 50 degrees Celsius.

3.2 road tankers for refrigerated liquefied gas: road transport tank vehicle for filling refrigerated liquefied gas, in which a vacuum insulated tank is permanently connected to a type-approved chassis or a semi-trailer running gear.

3.3 tank truck: road transport tank vehicle in which the tank is mounted on a type-approved chassis.

3.4 semi-trailer: road transport tank vehicle in which the tank is mounted on a non-powered semi-trailer running gear.

3.5 high vacuum multilayer insulation: insulation method in which multiple radiation shields separated by insulating material are arranged in the vacuum interlayer space of the tank and a high vacuum is drawn.

3.6 vacuum powder insulation: insulation method in which the vacuum interlayer space of the tank is filled with porous fine-particle insulating material and evacuated.

3.7 geometric volume: internal volume of the inner vessel determined from the design geometric dimensions, deducting the volume occupied by internal parts.

3.8 effective volume: maximum liquid volume of refrigerated liquefied gas that the inner vessel is permitted to be filled with in the service condition.

3.9 equivalent pressure: pressure borne by the tank caused by the inertial force loads of the medium under normal transport conditions.

3.10 filling rate: ratio of the liquid volume of refrigerated liquefied gas filled in the tanker to the geometric volume of the inner vessel.

3.11 specified filling rate: ratio of the liquid volume, when the filled liquid reaches the maximum liquid level specified by the design during filling of the tanker, to the geometric volume of the inner vessel.

3.12 reference steel: reference steel with a specified lower limit of standard tensile strength (Rm) of 370 MPa and an elongation after fracture (A) of 27%.

3.13 sealing-off vacuum degree: vacuum degree of the vacuum interlayer at ambient temperature when the pressure has become relatively stable after the tank evacuation has been completed and sealed.

4 Qualification and responsibilities

4.1.1 In addition to complying with this standard, the design, manufacture, inspection and acceptance of tankers shall comply with the relevant laws, regulations and safety technical specifications promulgated by the state.

4.1.2 The design and manufacturing units of tankers shall obtain the corresponding special equipment design and manufacturing licences in accordance with TSG R0005.

4.1.3 In addition to holding the corresponding special equipment manufacturing licence, the manufacturing unit of tankers shall obtain the corresponding product manufacturing qualification in accordance with the regulations of the automotive industry authority of the State Council.

4.2.1 The user or the party commissioning the design shall submit the design conditions of the tanker to the design unit in formal written form. The design conditions shall include at least the following items.

a) The main standards and safety technical specifications to be followed in design and manufacture.

b) Operating conditions, including ambient temperature of use, operating temperature range, operating pressure range, loading/unloading conditions and methods, loading/unloading pressure, additional loads, road conditions etc.

c) Filled medium, including the number, name, category, composition, physical and chemical properties, hazard characteristics and content of harmful impurities of the medium, and the corrosion rate of the medium on the tank materials.

d) Geometric volume or effective volume of the inner vessel; e) expected service life of the tanker and service life of the interlayer vacuum; f) required holding time.

g) Number of pressure cycles corresponding to fluctuating pressure; h) model and necessary technical parameters of the type-approved chassis or tractor.

i) Other conditions necessary for the design (such as selection of tank materials, corrosion protection, surface treatment and special tests).

4.2.2.1 The design unit shall complete the design of the complete vehicle on the basis of the content of the risk assessment report, and shall be responsible for the correctness and completeness of the design documents.

4.2.2.2 The management and use of the special design seal shall meet the requirements of TSG R0005.

4.2.2.3 The design unit shall keep all design documents for the design service life of the tanker.

4.2.3.1 The tanker shall be manufactured as a complete vehicle, and the manufacturing unit is responsible for the manufacturing quality of the tanker.

4.2.3.2 The manufacturing unit shall manufacture in accordance with the requirements of the design documents. When the original design documents need to be modified, written evidence of the original design unit's consent to the modification shall be obtained, and detailed records of the modified parts shall be made.

4.2.3.3 Before manufacture, the manufacturing unit shall prepare a quality plan, whose content shall include at least the manufacturing process control points, inspection items and acceptance requirements of the tanker.

4.2.3.4 During manufacture and after completion, the inspection department of the manufacturing unit shall carry out the various inspections and tests in accordance with this standard, the design drawings, the design documents and the quality plan, issue the corresponding reports, and be responsible for the correctness and completeness of the reports.

4.2.3.5 After each tanker has passed inspection, the manufacturing unit shall issue a product certificate of conformity.

4.2.3.6 The manufacturing unit shall accept supervisory inspection of its manufacturing process by a special equipment inspection and testing institution, and obtain the 'Special equipment manufacturing supervisory inspection certificate' issued by the supervisory inspection unit.

4.2.3.7 The tanker shall pass, by model, the type test and related tests of a test institution verified or approved by the competent authority, and obtain the corresponding certificates of conformity.

4.2.3.8 For each tanker it manufactures, the manufacturing unit shall keep at least the following technical documents for reference within the design service life: a) manufacturing process drawings or process cards; b) welding procedure and heat treatment procedure documents of the tank; c) records of the inspection and test items specified by the standard; d) inspection, examination and test records during manufacture and after completion; e) delivery documents (in accordance with Clause 12); f) original design documents.

5 Materials

5.1.1 The selection of materials shall take into account the mechanical properties, physical properties, processing properties of the materials and their compatibility with the medium.

5.1.2 For materials that may come into contact with oxygen or an oxygen-enriched environment, compatibility with oxygen shall comply with GB/T 31481.

5.1.3 Materials of non-pressure components welded to pressure components shall have good toughness and weldability and shall match the pressure components to which they are welded.

5.1.4 The material manufacturer shall make clear and durable factory stamp marks or other traceable marks in a conspicuous position on the material.

5.1.5 The material manufacturer shall provide the tanker manufacturing unit with a material quality certificate, whose content shall be complete and clear, bearing a printed traceable information mark and the quality inspection stamp.

5.1.6 When the manufacturing unit obtains tank materials from a unit other than the material manufacturer, it shall obtain the original of the material quality certificate provided by the material manufacturer, or a copy stamped with the official seal of the material distributor and the seal of the responsible person handling it.

5.1.7 The manufacturing unit shall be responsible for the authenticity and consistency of the quality certificates of the materials and purchased parts obtained.

5.2.1 Materials selected for the tank shall comply with GB/T 150.2 and the corresponding national and industry standards. When selecting materials for tank pressure components, the service conditions of the materials (such as design temperature, design pressure, medium characteristics and operating features), the properties of the materials (mechanical, processing, chemical and physical properties), the manufacturing process of the tank and economic rationality shall be considered.

5.2.2 The use of materials of foreign grades or new materials shall comply with the relevant provisions of TSG R0005.

5.2.3.1 Materials of pressure components of the inner vessel shall comply with the corresponding material standards and the design drawings.

5.2.3.2 Austenitic stainless steel materials shall generally be selected for pressure components of the inner vessel.

5.2.3.3 a) Steel for pressure components of the inner vessel shall have good plasticity; its standard value of yield strength (or 0.2% proof strength) at ambient temperature shall be not more than 460 MPa, and the standard upper limit of tensile strength shall be not more than 725 MPa.

5.2.3.3 b) The ratio of the room temperature yield strength (or 0.2% proof strength) to the room temperature tensile strength stated in the material quality certificate shall be not more than 0.85.

5.2.3.3 c) The elongation after fracture of steel plates shall be not less than 10 000/Rm (%), and that of austenitic stainless steel shall be not less than 40%. Elongation values obtained with specimens of different dimensions shall be converted in accordance with GB/T 17600, and the converted values shall meet this clause.

5.2.4.1.1 Steel for the outer shell shall be killed steel.

5.2.4.1.2 Low temperature steel plates and low temperature steel forgings used for design temperatures lower than minus 20 degrees Celsius shall additionally be produced by out-of-furnace refining.

5.2.4.2.1 For low alloy steel for welding, the carbon content shall be not more than 0.250%, the phosphorus content not more than 0.035% and the sulphur content not more than 0.035% (heat analysis).

5.2.4.2.2 For low alloy steel (plates and forgings): a) phosphorus content not more than 0.030% and sulphur content not more than 0.020%; b) for steel used at design temperatures lower than minus 20 degrees Celsius with a standard lower limit of tensile strength not more than 540 MPa, phosphorus content not more than 0.025% and sulphur content not more than 0.012%.

5.2.4.3.1 For low alloy steel for the outer shell, the standard value of yield strength at ambient temperature shall be not more than 460 MPa and the standard upper limit of tensile strength not more than 725 MPa; the steel shall be suitable for the environmental conditions encountered in transport and service of the tanker and meet the design drawings.

5.2.4.3.2 For low alloy steel for the outer shell, the ratio of yield strength to tensile strength at ambient temperature stated in the material quality certificate shall be not more than 0.85.

5.2.4.3.3 Impact tests of low alloy steel plates and forgings for the outer shell: a) the impact test temperature shall be as required by the design documents; b) the minimum Charpy V-notch impact absorbed energy (KV2) shall comply with Table 1; c) where the impact energy specified in the steel standard is higher than Table 1, the steel standard shall also be met; d) steel plates less than 6 mm thick may be exempted from impact testing.

Table 1, impact absorbed energy of low alloy steel plates and forgings — standard lower limit of tensile strength Rm not more than 510 MPa: average KV2 of 3 standard specimens not less than 27 J.

Table 1 — standard lower limit of tensile strength Rm above 510 MPa up to 540 MPa: average KV2 of 3 standard specimens not less than 34 J.

Note to Table 1: for steels whose Rm decreases with increasing thickness, the impact absorbed energy requirement is determined by the Rm of the minimum thickness range of the steel.

5.2.4.3.4 The sampling location and orientation of Charpy impact specimens shall comply with the corresponding steel standard. Each set of impact tests shall consist of 3 standard specimens (10 mm wide); one specimen is permitted to be below the value of Table 1 but not below 70% of it. When standard specimens cannot be prepared, sub-size specimens 7.5 mm or 5 mm wide shall be used in turn, with required impact energy of 75% or 50% of that for standard specimens respectively.

5.2.4.3.5 Elongation after fracture (A): a) for steel plates of outer shell heads and shells, A shall be not less than 10 000/Rm (%) and not less than 20%; b) where the steel plate standard specifies a higher A than a), the plate standard shall also be met; c) A of plates and forgings for other pressure components of the outer shell shall comply with the corresponding steel standard; d) values from specimens of different dimensions shall be converted per GB/T 17600 and meet a), b) and c).

5.2.5.1.1 Austenitic stainless steel plates for the inner vessel shall comply with GB/T 24511 and be delivered in the solution treated condition. The surface finish of hot rolled plates shall be not lower than grade 1D, and that of cold rolled plates not lower than grade 2B.

5.2.5.1.2 The mechanical property indices of steel plates commonly used for the inner vessel shall be as specified in Table 2.

5.2.5.1.3 When steel plates other than those in Table 2 are used, they shall comply with this standard and the corresponding material standards.

Table 2, S30408 to GB/T 24511, solution treated, thickness 3 mm to 25 mm: Rp0.2 not less than 220 MPa, Rp1.0 not less than 250 MPa, Rm not less than 520 MPa, elongation A not less than 40%.

Table 2, S30403 to GB/T 24511, solution treated, thickness 3 mm to 25 mm: Rp0.2 not less than 210 MPa, Rp1.0 not less than 230 MPa, Rm not less than 490 MPa, elongation A not less than 40%.

Table 2, S31608 to GB/T 24511, solution treated, thickness 3 mm to 25 mm: Rp0.2 not less than 220 MPa, Rp1.0 not less than 260 MPa, Rm not less than 520 MPa, elongation A not less than 40%.

Table 2, S31603 to GB/T 24511, solution treated, thickness 3 mm to 25 mm: Rp0.2 not less than 210 MPa, Rp1.0 not less than 260 MPa, Rm not less than 490 MPa, elongation A not less than 40%.

5.2.5.2.1 Steel plates for the outer shell shall have good weldability, sufficient strength and impact toughness, taking into account corrosion by the external environment. Low alloy steel plates shall comply with GB/T 713 or GB/T 3531; austenitic stainless steel plates shall comply with GB/T 24511.

5.2.5.2.2 The mechanical property indices of steel plates commonly used for the outer shell shall be as specified in Table 3; 5.2.5.2.3 when steel plates other than those in Table 3 are used, they shall comply with this standard and the corresponding material standards.

Table 3, Q245R to GB/T 713, hot rolled, controlled rolled or normalized, thickness 3 mm to 16 mm: ReL (Rp0.2) not less than 245 MPa, Rm 400 MPa to 520 MPa, elongation A not less than 25%.

Table 3, Q345R to GB/T 713, hot rolled, controlled rolled or normalized, thickness 3 mm to 16 mm: ReL (Rp0.2) not less than 345 MPa, Rm 510 MPa to 640 MPa, elongation A not less than 21%.

Table 3, 16MnDR to GB/T 3531, normalized or normalized and tempered, thickness 6 mm to 16 mm: ReL (Rp0.2) not less than 315 MPa, Rm 490 MPa to 620 MPa, elongation A not less than 21%.

Table 3, S30408 to GB/T 24511, solution treated, thickness 3 mm to 25 mm: Rp0.2 not less than 220 MPa, Rm not less than 520 MPa, elongation A not less than 40%.

Table 3, S30403 to GB/T 24511, solution treated, thickness 3 mm to 25 mm: Rp0.2 not less than 210 MPa, Rm not less than 490 MPa, elongation A not less than 40%.

5.2.6.1 Stainless steel forgings for the inner vessel shall comply with NB/T 47010, with a forging grade not lower than grade III.

5.2.6.2 Low alloy steel forgings and stainless steel forgings for the outer shell shall comply with NB/T 47009 and NB/T 47010 respectively; forgings in contact with the medium in the tank shall be not lower than grade III, and other forgings not lower than grade II.

5.2.7.1 Materials for steel pipes shall comply with GB/T 150.2 and the design drawings, and shall comply with GB/T 13296 or GB/T 14976.

5.2.7.2 Pipe fittings shall comply with the corresponding standards. When pipe fittings are made from steel forgings, they shall comply with 5.2.6.

5.2.7.3 When pipe fittings are formed by cold forming, the measured ferrite content after forming shall be not more than 15%.

5.2.8.1 Expanded perlite (pearlite sand) for vacuum powder insulation shall meet the following: a) particle size 0.1 mm to 1.2 mm; b) bulk density 30 kg to 60 kg per cubic metre; c) moisture content not more than 0.3% (by mass); d) thermal conductivity (average value at atmospheric pressure between 77 K and 310 K) not more than 0.03 W/(m K).

5.2.8.2 The opacifier shall have good chemical stability.

5.2.8.3 High vacuum multilayer insulation materials shall comply with GB/T 31480, and degreased fibre cloth or degreased fibre paper with low thermal conductivity and low outgassing rate shall be used.

5.2.9.1 5A molecular sieve shall comply with GB/T 13550, and 13X molecular sieve shall comply with HG/T 2690; 5.2.9.2 palladium oxide shall comply with YS/T 599.

5.2.10.1 Welding materials for the tank shall comply with NB/T 47018.1 to NB/T 47018.4 and shall bear clear and durable marks.

5.2.10.2 Selection of welding materials shall consider matching of the mechanical properties of the welded joint with the tank base metal. The tensile strength of the weld metal shall be not lower than the lower limit specified in the base metal standard, and the impact absorbed energy of low alloy steel welding materials shall comply with Table 1. When required, other properties shall also be not lower than the corresponding requirements of the base metal.

5.2.10.3 Welding materials shall be subject to welding procedure qualification in accordance with NB/T 47014 and may be used only after passing the qualification.

5.2.11.1 Non-metallic support materials shall as far as possible be materials with low thermal conductivity, low surface outgassing rate under vacuum and good low temperature impact toughness, and shall be used within their permitted service temperature range.

5.2.11.2 Metallic support materials shall be materials with low thermal conductivity and good low temperature impact toughness, used within their permitted service temperature range and complying with the corresponding material standards.

5.2.12.1 Purchased parts shall comply with the corresponding national or industry standards and be accompanied by quality certification documents or product certificates of conformity.

5.2.12.2 The type-approved chassis shall be a type-approved product recognized by the automotive authority of the State Council, with corresponding technical data and quality certification documents. When an imported vehicle chassis is used, it shall comply with the relevant regulations of the national competent authority and have corresponding technical data and quality certification documents.

5.2.12.3 The semi-trailer running gear shall meet the requirements of GB/T 23336 and have corresponding technical data and quality certification documents.

5.2.12.4 Portable fire extinguishers shall comply with GB 4351 and be within their period of validity.

5.2.12.5 Imported pressure piping components such as valves shall also comply with the relevant regulations of the General Administration of Quality Supervision, Inspection and Quarantine.

5.2.12.6 Fasteners shall comply with the corresponding national or industry standards.

5.2.12.7 Sealing gaskets shall be correctly selected according to the filled medium, operating pressure and temperature, and comply with the corresponding standards. When PTFE gaskets are used, expanded or filled modified PTFE gaskets shall be selected.

5.2.12.8 Support materials shall have sufficient strength and impact toughness; 5.2.12.9 other materials for tankers shall meet the requirements of the design drawings.

6 Design

6.1.1 In addition to this standard, the design of tankers shall comply with the relevant regulations, safety technical specifications, national standards and industry standards. The arrangement of the tank, piping, safety accessories, instruments and loading/unloading accessories shall meet the requirements of use and safety.

6.1.2 The overall dimensions, axle loads and mass limits of the tanker shall comply with GB 1589; the axle load distribution shall be reasonable, and the axle loads and total mass shall not exceed the permitted limits of the type-approved chassis or semi-trailer.

6.1.3 The maximum side tilt stability angle of the tanker to the left and right in the fully loaded static condition shall comply with GB 7258.

6.1.4 The braking devices and braking performance of the tanker shall comply with GB 7258, GB 12676 and GB/T 23336, and semi-trailers shall adopt a dual-line braking system.

6.1.5 The rear overhang of the tanker shall comply with GB 1589.

6.1.6 The tanker shall be fitted with lateral protection devices complying with GB/T 11567. The tank and the piping, safety accessories, instruments and loading/unloading accessories on the tank shall not protrude beyond the lateral protection devices.

6.1.7 The tanker shall be fitted with a rear underrun protection device complying with GB/T 11567, with sufficient strength and rigidity to protect the tank, piping, safety accessories, instruments and loading/unloading accessories in an accidental collision; the distance in the length direction between its inner side and the vertical projection of the outer end faces of the rear head of the tank and of the piping, safety accessories, instruments and loading/unloading accessories at the rear of the tank shall be not less than 150 mm.

6.1.8 Pipe connections, loading/unloading valves, overpressure relief devices, emergency shut-off devices, instruments and other accessories of the tanker shall be reasonably arranged and relatively concentrated for ease of operation, inspection and maintenance, and as far as possible located in the operating cabinet for protection. Piping and valves shall be clearly identified with their purpose.

6.1.9 The operating cabinet of the tanker shall have sufficient operating space, be firmly connected and be arranged to meet the requirements of vehicle use.

6.1.10 When the tanker is fitted with a self-pressurizer, it shall be installed in a safe and reliable location.

6.1.11 The number, position and light colour of the external lighting and light-signalling devices of the tanker shall comply with GB 4785.

6.1.12 Each side of the tanker shall be equipped with at least one portable fire extinguisher of not less than 4 kg, securely fixed and easy to take out.

6.1.13 Tank trucks and semi-trailer tractors shall be fitted with a speed limiting device, a satellite positioning device with driving recorder function, and a retarder or other auxiliary braking system.

6.1.14 The front turning radius and rear clearance radius of the semi-trailer shall meet GB/T 20070.

6.1.15 The semi-trailer running gear shall comply with GB/T 23336.

6.1.16 The kingpin of the semi-trailer shall comply with GB/T 4606 or GB/T 4607.

6.1.17 The axles and suspension of the semi-trailer shall comply with GB/T 23336.

6.1.18 The arrangement of the semi-trailer support device (landing gear) shall not affect the turning of the tractor; the support device shall comply with QC/T 310, and its ground clearance in the travelling condition shall be not less than 320 mm.

6.1.19 Tankers filled with flammable or explosive media shall meet the following: a) the exhaust spark arrester shall be located forward of the front end face of the tank in a zone not higher than the upper plane of the vehicle longitudinal beams, and shall comply with GB 13365; b) the structure and safety technical requirements of the tank and its additional equipment shall comply with the relevant provisions of GB 21668 and GB 20300.

6.1.20 The design service life of the tank shall be not less than 10 years.

6.2.1 a) The design documents of the tanker shall include at least a risk assessment report, covering the main failure modes and risk control in the design, manufacture and use stages, whose basic content shall comply with Annex B.

6.2.1 b) Design specification, including the main physical and chemical properties of the filled medium (number, name, category, saturated vapour pressure and density corresponding to operating temperature etc.), hazard characteristics, limiting composition of mixed media, limiting content of harmful impurities and compatibility with tank materials, and explanations of the selection of design codes and standards, principles for determining the main design structure and main design parameters, and the selection of materials, safety accessories, instruments, loading/unloading accessories and main purchased parts (such as type-approved chassis or running gear).

6.2.1 c) Design calculation report, including calculations of tank strength, stiffness, external pressure stability, volume, heat transfer, safety relief rate, discharge capacity of overpressure relief devices and strength of internal and external support structures, stress check at the connection between tank and running gear or chassis, axle load distribution, side tilt stability and centre of gravity of the tanker, and where necessary stress analysis of the tanker structure.

6.2.1 d) Design drawings, including general assembly drawing, drawings of the tank and components, piping system and flow diagrams; e) manufacturing technical conditions, including main manufacturing process requirements and inspection and test methods.

6.2.1 f) Instructions for use, including main technical performance parameters, applicable media, specifications and connection methods of safety accessories, instruments and loading/unloading accessories, operating instructions, precautions for use, necessary warnings and emergency measures.

6.2.2 The general assembly drawing, tank drawing, risk assessment report and design calculation report shall be signed at the three levels of design, checking and review, and approved by the technical director of the design unit or a person authorized by him.

6.2.3 The general assembly drawing shall indicate at least: a) product name, model and the main safety technical specifications and standards on which design and manufacture are based; b) operating conditions, including ambient temperature of use, operating temperature, operating pressure and medium characteristics (degree of explosion hazard etc.).