1、BS EN 1736:2008ICS 27.080;27.200NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDRefrigerating systemsand heat pumps Flexible pipe elements,vibration isolators,expansion joints andnon-metallic tubes Requirements, designand installationThis British Standardwas pub
2、lished under theauthority of the StandardsPolicy and StrategyCommittee on 28 February2009 BSI 2009ISBN 978 0 580 61493 4Amendments/corrigenda issued since publicationDate CommentsBS EN 1736:2008National forewordThis British Standard is the UK implementation of EN 1736:2008. Itsupersedes BS EN 1736:2
3、000 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee RHE/18, Refrigeration safety.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof
4、 a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.BS EN 1736:2008EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 1736November 2008ICS 27.080; 27.200 Supersedes EN 1736:2000 English VersionRefrigerating sys
5、tems and heat pumps - Flexible pipe elements,vibration isolators, expansion joints and non-metallic tubes -Requirements, design and installationSystmes de rfrigration et pompes chaleur - Elmentsflexibles de tuyauterie, isolateurs de vibration, joints dedilatation et tubes non mtalliques - Exigences,
6、 conceptionet installationKlteanlagen und Wrmepumpen - FlexibleRohrleitungsteile, Schwingungsabsorber, Kompensatorenund Nichtmetall-Schluche - Anforderungen, Konstruktionund EinbauThis European Standard was approved by CEN on 5 October 2008.CEN members are bound to comply with the CEN/CENELEC Intern
7、al Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.
8、This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are
9、the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerlan
10、d and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 1736:2
11、008: EBS EN 1736:2008EN 1736:2008 (E) 2 Contents Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Applications .7 5 Materials .10 6 Pressure and pulsation requirements .10 7 Permeability of non-metallic flexible tubes.11 8 Internal cleaness, internal hum
12、idity and permeability of water vapour.13 9 End connections13 10 Pre-charged flexible pipe elements .13 11 Marking .13 12 Documentation.14 BS EN 1736:2008EN 1736:2008 (E) 3 Foreword This document (EN 1736:2008) has been prepared by Technical Committee CEN/TC 182 “Refrigerating systems, safety and en
13、vironmental requirements”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2009, and conflicting national standards shall be withdrawn at the latest by
14、 May 2009. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 1736:2000. According to the CEN/CENELEC Interna
15、l Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta
16、, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 1736:2008EN 1736:2008 (E) 4 Introduction The use of flexible pipe elements is required where impermissible stresses are to be eliminated from refrigerating circuits and pipe
17、 expansion or relative movements of components are to be absorbed. The use of flexible pipe elements should not be specified unless it is necessary in the design of refrigerant circuits. If necessary, they should be designed and installed in accordance with this standard. Flexible pipe elements are
18、often the weakest part of a refrigerating system and the part most likely to suffer from fatigue or stress corrosion cracking. BS EN 1736:2008EN 1736:2008 (E) 5 1 Scope This document describes requirements, design and installation of flexible pipe elements (e. g. metallic flexible pipe, metallic fle
19、xible tube, vibration isolator, expansion joint) and non-metallic tube used in the refrigerant circuits of refrigerating systems and heat pumps. It also describes the requirements to qualify the tightness of non-metallic tubes (e.g. plastic) used in evaporating and/or condensing sides of refrigerati
20、ng systems and heat pumps. It does not apply to flexible pipes that are only occasionally stressed beyond the elastic limit, e. g. during repair work, or to joints which are free to rotate or hinge. 2 Normative references The following referenced documents are indispensable for the application of th
21、is document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 378-1:2008, Refrigerating systems and heat pumps Safety and environmental requirements Part 1: Basic requirements, definitio
22、ns, classification and selection criteria EN 378-2:2008, Refrigerating systems and heat pumps Safety and environmental requirements Part 2: Design, construction, testing, marking and documentation EN ISO 175, Plastics - Methods of test for the determination of the effects of immersion in liquid chem
23、icals (ISO 175:1999) ISO 6605:2002, Hydraulic fluid power Hoses and hose assemblies Test methods 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 378-1:2008 and the following apply. 3.1 flexible pipe element any form of pipe or tube connecting two poin
24、ts which may move relative to each other NOTE 1 This generic term includes all types, as defined in 3.2 to 3.6. NOTE 2 Flexible pipe elements may include a plastic barrier in the construction, either as a liner on the inner surface or as a sandwich in the pipe wall. The main purpose of such a barrie
25、r is to reduce the permeation of refrigerant gas. 3.2 metallic flexible pipe readily flexible, small bore pipe, e. g. capillary tube which is capable of movement within its elastic limit during operation of the refrigerating system (see Figure 1) NOTE This type of pipe is flexible by virtue of the s
26、hape into which the tube is bent, e. g. coiled capillary tube. 3.3 metallic flexible tube tubular flexible element designed to bend within defined limits and containing a corrugated metal bellows, the corrugations of which may be annular or spiral (see Figure 1) BS EN 1736:2008EN 1736:2008 (E) 6 NOT
27、E 1 Metallic flexible tubes may be reinforced by metallic braiding which may be covered by rubber or plastic but the whole element should be designed so that, when bent within pre-determined limits, it is not stressed beyond the elastic limit. NOTE 2 This type of pipe is flexible by virtue of its de
28、sign and construction, e. g. bellows. 3.4 non-metallic flexible tube tubular flexible element designed to bend within defined limits (see Figure 1) NOTE 1 Non-metallic flexible tubes may have smooth bore or corrugated bore and they may be reinforced to withstand pressure, vacuum or external impact.
29、NOTE 2 This type of pipe is flexible by virtue of its material, e. g. elastomer. NOTE 3 For non-metallic flexible tube are to be intended all the pipes made of plastic or rubber: mono-layer, multi-layer, reinforced and non-reinforced ones. BS EN 1736:2008EN 1736:2008 (E) 7 Flexible Pipe Elements met
30、allic flexibe pipe (3.2) metallic flexible tube (3.3) non-metallic flexible tube (3.4) flexibility is configuration dependent (e. g. coils) flexibility is construction dependent (e. g. bellows) flexibility is material dependent (e. g. elastomer) Figure 1 Types of flexible pipe elements 3.5 expansion
31、 joint tubular pipe element shaped in such a way that it provides limited movement to accommodate thermal expansion without reaching its elastic limit 3.6 vibration isolator short flexible tube usually of metallic construction which is intended to reduce the effects of vibration from the compressor
32、to other parts of the refrigerating system or vice versa 3.7 maximum allowable pressure PS maximum pressure for which the equipment is designed, as specified by the manufacturer 3.8 maximum/minimum allowable temperature TS maximum/minimum temperature for which the equipment is designed, as specified
33、 by the manufacturer 4 Applications 4.1 General 4.1.1 The refrigerating system shall be so designed and constructed that the components being connected by the flexible pipe elements and non-metallic tubes cannot move in such a way as to stress the pipe element beyond its elastic limit. 4.1.2 Flexibl
34、e pipe elements and non-metallic tubes shall be installed in accordance with the manufacturers instructions. 4.1.3 Flexible pipe elements, vibration isolators, expansion joints and non-metallic tubes shall be used only if necessary. BS EN 1736:2008EN 1736:2008 (E) 8 4.2 Significantly moved flexible
35、pipe elements NOTE Such elements are subjected to regular movement through significant distance to allow the operation of refrigerating equipment such as plate freezers. 4.2.1 Significantly moved flexible pipe elements shall be supported and connected in such a way that they are not bent to radii le
36、ss than those specified by the manufacturer. 4.2.2 Significantly moved flexible pipe elements shall not allow the generation of static electricity when non-conducting refrigerants pass through them at high velocity. NOTE This may be achieved by the use of antistatic plastic as lining. 4.2.3 Signific
37、antly moved flexible pipe elements shall be so installed that there is no danger of the outer covering being abraded on stationary objects during movement of the flexible pipe. 4.2.4 Significantly moved flexible pipe elements shall be so constructed and connected that they are not liable to damage b
38、y the freezing of water or by corrosion by humidity at the surface or at joints. 4.2.5 The manufacturer of significantly moved non-metallic flexible tubes shall specify the permeability of the pipe element to water vapour and to the refrigerants for which it is suitable (see Clauses 7 and 8). 4.3 In
39、termittently moved flexible pipe elements NOTE Such elements move intermittently to take up relative movement between components of the refrigerating system. 4.3.1 Intermittently moved flexible pipe elements shall be supported and connected in such a way that they are not bent to radii less than tho
40、se specified by the manufacturer. 4.3.2 Intermittently moved flexible pipe elements shall not allow the generation of static electricity when non-conducting refrigerants pass through them at high velocity. NOTE This may be achieved by the use of antistatic plastic as lining. 4.3.3 Intermittently mov
41、ed flexible pipe elements shall be so installed that there is no danger of the outer covering being abraded on stationary objects during movement of the flexible pipe. 4.3.4 Intermittently moved flexible pipe elements shall be so constructed and connected that they are not liable to damage by the fr
42、eezing of water or by corrosion by humidity at the surface or at joints. 4.3.5 The manufacturer of intermittently moved non-metallic flexible tubes shall specify the permeability of the pipe element to water vapour and to the refrigerants for which it is suitable (see Clauses 7 and 8). 4.4 Fixed ins
43、talled flexible pipe elements NOTE Such elements are used to minimise assembly difficulty by accommodating slight misalignments or relative movement between components of the refrigerating system. 4.4.1 Fixed installed flexible pipe elements shall be supported and connected in such a way that they a
44、re not bent to radii less than those specified by the manufacturer. 4.4.2 Fixed installed flexible pipe elements shall not allow the generation of static electricity when non-conducting refrigerants pass through them at high velocity. NOTE This may be achieved by the use of antistatic plastic as lin
45、ing. BS EN 1736:2008EN 1736:2008 (E) 9 4.4.3 Fixed installed flexible pipe elements shall be so constructed and connected that they will not be damaged by freezing of water or by corrosion by humidity at the surface or at joints. 4.4.4 The manufacturer of fixed installed non-metallic flexible tubes
46、shall specify the permeability of the pipe element to water vapour and to the refrigerants for which it is suitable (see Clauses 7 and 8). 4.5 Vibration isolators NOTE 1 Vibration isolators are commonly used as suction and discharge connections for compressors and are also sometimes used as connecti
47、ons to evaporators and condensers. NOTE 2 Vibration isolators are not suitable for preventing the transmission of gas pulsation. 4.5.1 Vibration isolators shall be so installed that they are not subjected to combined bending and twisting. 4.5.2 Vibration isolators shall be so installed that they can
48、 accommodate not only the vibration emanating from a running compressor but also the movement of a spring mounted compressor at starting and stopping. 4.5.3 Where the vibration to be isolated has components in more than one plane, care shall be taken to ensure that the axis of the vibration isolator
49、 enables all these components to be accommodated. If necessary, two vibration isolators connected at right angles to each other shall be installed. 4.5.4 Vibration isolators shall be firmly anchored at the point where they join the fixed piping of the refrigerating system. 4.5.5 Vibration isolators shall be so constructed and connected that they are not liable to damage by freezing of water at the surface or at joints. In particular they shall not be installed vertically, unless a waterproof sleeve has been tightly fitted over the isolator. 4.5.6 Vibra
