1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58cryogenic service Part 2: Non-reclosable pressure-relief devices ICS 23.020.40Cryogenic vessels Pre
2、ssure-relief accessories for BRITISH STANDARDBS ISO 21013-2:2007BS ISO 21013-2:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 August 2007 BSI 2007ISBN 978 0 580 54553 5Amendments issued since publicationAmd. No. Date CommentsComplianc
3、e with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard is the UK implementation of ISO 21013-2:2007.The UK participation in its preparation was entrusted to Technical Committee PVE/18, Cryogenic vessels.A list of organizations represented on th
4、is committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Reference numberISO 21013-2:2007(E)INTERNATIONAL STANDARD ISO21013-2First edition2007-06-15Cryogenic ves
5、sels Pressure-relief accessories for cryogenic service Part 2: Non-reclosable pressure-relief devices Rcipients cryogniques Dispositifs de scurit pour le service cryognique Partie 2: Dispositifs de scurit non refermables BS ISO 21013-2:2007ii iiiForeword ISO (the International Organization for Stand
6、ardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right
7、to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International St
8、andards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an I
9、nternational Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 210
10、13-2 was prepared by Technical Committee ISO/TC 220, Cryogenic vessels. ISO 21013 consists of the following parts, under the general title Cryogenic vessels Pressure-relief accessories for cryogenic service: Part 1: Reclosable pressure-relief valves Part 2: Non-reclosable pressure-relief devices Par
11、t 3: Sizing and capacity determination BS ISO 21013-2:2007blank1Cryogenic vessels Pressure-relief accessories for cryogenic service Part 2: Non-reclosable pressure-relief devices 1 Scope This International Standard specifies the requirements for the design, manufacture and testing of non-reclosable
12、pressure-relief devices for cryogenic service, i.e. for operation with cryogenic fluids in addition to operation at temperatures from ambient to cryogenic. This International Standard is restricted to bursting-disc and buckling-pin devices not exceeding a size of DN 200 designed to relieve single-ph
13、ase vapours or gases. A bursting-disc or buckling-pin assembly may be specified, constructed and tested such that it is suitable for use with more than one gas or with mixtures of gases. NOTE This International Standard does not provide methods for determining the capacity of bursting-disc or buckli
14、ng-pin devices for a particular cryogenic vessel. Such methods are provided in ISO 21013-3. 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 editi
15、on of the referenced document (including any amendments) applies. ISO 4126-2, Safety devices for protection against excessive pressure Part 2: Bursting disc safety devices ISO 20421-1, Cryogenic vessels Large transportable vacuum-insulated vessels Part 1: Design, fabrication, inspection and testing
16、ISO 21009-1, Cryogenic vessels Static vacuum-insulated vessels Part 1: Design, fabrication, inspection, and tests IS 21010, Cryogenic vessels Gas/materials compatibility ISO 21028-1, Cryogenic vessels Toughness requirements for materials at cryogenic temperature Part 1: Temperatures below 80 C ISO 2
17、1028-2, Cryogenic vessels Toughness requirements for materials at cryogenic temperature Part 2: Temperatures between 80 C and 20 C ISO 21029-1, Cryogenic vessels Transportable vacuum insulated vessels of not more than 1 000 litres volume Part 1: Design, fabrication, inspection and tests ISO 23208, C
18、ryogenic vessels Cleanliness for cryogenic service BS ISO 21013-2:20072 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 4126-2 and the following apply. 3.1 DN (nominal size) alphanumeric designation of size for components of a pipework system, which
19、is used for reference purposes and which comprises the letters DN followed by a dimensionless whole number which is indirectly related to the physical size, in millimetres, of the bore or outside diameter of the end connections NOTE Adapted from ISO 6708:1995. 3.2 pressure gauge pressure pressure fo
20、r which the value is equal to the algebraic difference between the absolute pressure and the atmospheric pressure 3.3 rated minimum temperature lowest temperature for which the pressure-relief device is rated 3.4 rated maximum temperature highest temperature for which the pressure-relief device is r
21、ated 3.5 coincident temperature temperature of the bursting disc associated with a burst pressure (see 3.11, 3.12 and 3.13 of ISO 4126-2:2003) and which is the expected temperature of the bursting disc when it is required to burst 3.6 cryogenic fluid fluid defined as cryogenic fluid in ISO 21029-1 o
22、r ISO 21009-1 or ISO 20421-1 NOTE This includes totally evaporated liquids and supercritical fluids. 4 Requirements 4.1 General Non-reclosing pressure-relief devices shall satisfy the requirements of ISO 4126-2. In the event of conflicting requirements, this International Standard takes precedence o
23、ver ISO 4126-2. 4.2 Design 4.2.1 Design temperature The rated minimum temperature shall be equal to the equilibrium temperature at atmospheric pressure of the coldest fluid to be relieved. The rated maximum temperature shall be +65 C unless a higher temperature is specified in the purchase order. 4.
24、2.2 Coincident temperature Unless otherwise specified in the purchase order, the coincident temperatures for normal ambient conditions and for fire conditions shall be 20 C and 427 C, respectively. Coincident temperatures for other conditions shall be specified in the purchase order. BS ISO 21013-2:
25、200734.2.3 Sublimating fluid service Where the pressure-relief device is specified as suitable for service with products that when vented to atmosphere from a pressure anywhere between the devices specified maximum and minimum operating pressures and at a temperature anywhere between the devices spe
26、cified maximum and minimum temperatures condense from gas or vapour directly to solid (e.g. CO2), the design shall be such as to avoid reduction of the discharge area below that required due to accumulation of solid product. 4.2.4 Inserts Where soft inserts are used to ensure leak tightness, the des
27、ign shall be such as to prevent cold flow of the insert to a degree that results in the device failing to operate correctly. 4.3 Materials 4.3.1 General Materials shall be compatible with the process fluid and shall be controlled by the manufacturer of the device by a specification ensuring control
28、of chemical content and physical properties, and quality at least equivalent to an internationally recognized standard. A test certificate providing the chemical content and physical property test results shall be provided with the pressure-relief device. Materials shall also be oxygen compatible if
29、 relevant (see 4.3.5.1). 4.3.2 Metallic materials Metallic materials shall be in conformity with ISO 21028-1 or ISO 21028-2 as appropriate to the rated minimum temperatures. These requirements apply to parts exposed to low temperatures in normal service. Metallic materials which do not exhibit ducti
30、le/brittle transition, and non-ferrous materials which can be shown to have no ductile/brittle transition do not require impact tests. Forged, rolled, wrought and fabricated components from raw materials from these processes need not be impact tested if the rated minimum temperature is higher than t
31、he ductile/brittle transition range temperatures of the material. Castings meeting the requirements of one of the applicable mandatory Appendices I and IV or II and III for Forgings and Rolled or Wrought Materials of ASME B16.34 need not be impact tested if the rated minimum temperature is higher th
32、an the ductile/brittle transition range temperatures of the material. At least one randomly selected sample material from each castings production lot not meeting the requirements of this paragraph shall be impact tested at the rated minimum temperature. 4.3.3 Non-metallic materials Non-metallic mat
33、erials are well established for use in non-integral bursting discs and in seals and gaskets. If such materials are to be used for structural parts, such as the holder, they shall have properties appropriate to the application and be in conformity with ISO 21028-1 or ISO 21028-2. Non-metallic materia
34、ls shall also have mechanical properties that allow the device to pass the tests defined in Clause 5; be resistant to sunlight, weather and aging; be compatible with 4.3.5.1. 4.3.4 Corrosion resistance In addition to normal atmospheric corrosive agents associated with industrial atmospheres, the env
35、ironment surrounding cryogenic vessels is characteristically one of persistent low ambient temperatures together with high humidity. Thus particular care shall be taken to ensure that the selected materials of the devices, BS ISO 21013-2:20074 together with any coating of the pressure-relief device,
36、 preclude the possibility of premature failure or any other malfunction. Aluminium discs shall be protected from corrosion on the atmospheric side only. Some copper alloys are susceptible to stress corrosion cracking; therefore, careful consideration is necessary before selection of these materials
37、for components under stress. 4.3.5 Gas/material compatibility 4.3.5.1 Oxygen compatibility If the rated minimum temperature is equal to or below the boiling point of air or the device is intended for service with oxygen products, the materials shall be oxygen compatible in accordance with ISO 21010.
38、 4.3.5.2 Hydrogen For hydrogen service, see ISO 11114-1 and ISO 11114-2. 4.3.5.3 Acetylene compatibility Metallic materials shall contain less than 70 % copper if specified for use with mixtures containing acetylene. 5 Testing 5.1 Type approval of bursting-disc holders Bursting-disc holder designs w
39、hich pass the tests specified in 14.2 and 14.4 of ISO 4126-2:2003 shall be considered type approved. 5.2 Production testing 5.2.1 Pressure and operational tests They shall be performed in accordance with the requirements of ISO 4126-2. Pressure-relief devices with a corrosion-resistant coating shall
40、 be tested with the coating. The pressure test medium shall be dry oil-free air or an inert gas such as nitrogen. 5.2.2 Additional tests for pressure-relief devices with non-replaceable bursting-disc assemblies 5.2.2.1 Leak tests Each pressure-relief device with a non-replaceable bursting-disc assem
41、bly shall be subjected to an appropriate leak test that will demonstrate the integrity of the joint between the bursting disc and its holder. Typical tests might include, but are not restricted to, the following: a mass spectrometer sensing helium, calibrated for a leak of 109cm3/s with vacuum on th
42、e outlet; a pneumatic leak test under water with a pressure of 70 % of the burst pressure on the inlet. There shall be no detectable leakage. The requirements of ISO 4126-2 apply. 5.2.2.2 Visual examination Each pressure-relief device with a non-replaceable bursting-disc assembly shall be subjected
43、to an appropriate examination which will demonstrate that only a single bursting disc or bursting-disc assembly is built into each device. The requirements of ISO 4126-2 apply. BS ISO 21013-2:200756 Cleanliness All parts shall be clean such that they satisfy the requirements of ISO 23208. 7 Burst-pr
44、essure tolerances The burst-pressure tolerance for bursting-disc devices at the rated disc temperature shall not exceed 15 % of marked burst pressure up to 3 bar and 5 % of marked burst pressure 3 bar and over. 8 Marking Marking shall be permanent and visible after installation. Marking shall consis
45、t of the following minimum information: a) manufacturers name or trade mark; b) manufacturers model/type reference; c) nominal size designation; d) material identification; e) rated maximum bursting pressure and rated minimum bursting pressure with coincident temperature, with appropriate units; or
46、f) rated bursting pressure and performance tolerance with coincident temperature, with appropriate units; g) direction of flow, if appropriate; h) number of this International Standard, i.e. ISO 21013-2; i) batch identity; j) manufacturers reference of the bursting-disc holder into which the burstin
47、g disc or bursting-disc assembly is to be installed (except where separate holders are not required); k) rated flow area of the bursted disc or bursted disc and assembly; l) year of manufacture; m) certified flow resistance coefficient or rated coefficient of discharge. 9 Prevention of substitution
48、Where bursting discs and their holders are specified with pin-coding or an equivalent system to prevent a replacement bursting disc with an incorrect specified bursting pressure being fitted, the disc manufacturer shall maintain records of the coding appropriate to the specified bursting pressure of
49、 each type of disc. The continued availability of such records shall be guaranteed by the manufacturer by effective back-up procedures. The manufacturer shall operate a Quality System that guarantees that the appropriate coding is applied to his products. BS ISO 21013-2:20076 Bibliography 1 ISO 6708, Pipework components Definition and selection of DN (nominal size) 2 ISO 11114-1, Transportable gas cylinders Compatibility of cylinder and valve materials with
