《BS EN 13941-2009 design and installation of preinsulated bonded pipe systems for district heating.pdf》由会员分享，可在线阅读，更多相关《BS EN 13941-2009 design and installation of preinsulated bonded pipe systems for district heating.pdf（124页珍藏版）》请在三一文库上搜索。
1、 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? EN 13941:2009 (E) 2 Contents Page Foreword . 5 Introduction . 6 1Scope 8 2Normative references 8 3Terms and definitions, units and symbols . 10 3.1Terms and definitions . 10 3.2Units and symbols 14 4General considerat
2、ions for system design 17 4.1General requirements . 17 4.2Service life 17 4.3Preliminary investigations 17 4.4Determination of project class . 18 4.5Design documentation 20 5Components and materials 23 5.1Basic requirements . 23 5.2Steel pipe components . 24 5.3Polyurethane foam insulation 27 5.4PE
3、casing . 27 5.5Expansion cushions . 27 5.6Valves and accessories 27 6Actions and limit states 28 6.1General . 28 6.2Simplified analysis procedure . 30 6.3Actions . 30 6.4Limit states. 32 7Installation 42 7.1General . 42 7.2Transportation and storage 42 7.3Excavation of pipe trench . 43 7.4Installati
4、on of pipes and components . 43 7.5Welding of the steel pipe and testing of the steel welds 44 7.6Strength pressure test and leak tightness test 52 7.7Assembly of casing pipes, joint installation and site insulation 53 7.8Backfilling of trench 54 7.9Pipe bends and other components . 55 7.10Setting i
5、nto operation . 56 7.11Special constructions . 56 7.12Construction work during the operation stage 57 Annex A (normative) Design of piping components under internal pressure . 58 A.1General . 58 A.2Symbols 58 A.3Straight pipe and bends . 59 A.3.1Straight pipes 59 A.3.2Bends 59 A.4Tees and branch con
6、nections 59 A.4.1General aspects and limitations 59 A.4.2Reinforcement . 60 ? EN 13941:2009 (E) 3 A.5Reducers and extensions . 62 A.5.1General . 62 A.5.2Minimum wall thickness of the cone . 62 A.5.3Offset reducers 63 A.6Dished ends . 63 A.6.1General . 63 A.6.2Minimum required wall thickness for inte
7、rnal pressure . 64 A.6.3Straight cylindrical shells . 64 Annex B (informative) Geotechnics and pipe-soil interaction . 65 B.1Scope 65 B.1.1General . 65 B.1.2General requirements . 65 B.2Symbols and units 65 B.3Soil parameters for global analysis (pipe-soil interaction) . 66 B.3.1Modelling pipe-soil
8、interaction 66 B.3.2Pipe to soil friction (axial) 67 B.3.3Coefficient of horizontal soil reaction (lateral) . 69 B.3.4Combined stiffness of PUR foam, expansion cushions and soil . 73 B.4Characteristic values for soil loads and soil parameters . 75 B.4.1General . 75 B.4.2Soil mechanics study . 76 B.5
9、Specific requirements for stability 77 B.5.1General . 77 B.5.2Vertical stability . 77 B.5.3Horizontal stability 79 B.6Specific requirements for parallel excavations . 79 B.6.1General . 79 B.6.2Reduced friction 79 B.7Requirements for soft soils and settlement areas . 79 B.7.1General . 79 B.7.2Differe
10、ntial settlements 80 B.8Ovalization and circumferential stresses from top load . 80 B.8.1Traffic load . 80 B.8.2Stresses and ovalization from top load 82 B.8.3Deflection . 85 Annex C (informative) Global- and cross sectional analysis . 86 C.1General . 86 C.2Symbols . 86 C.3Survey of limit states for
11、 steel . 88 C.4Locations to be assessed 89 C.4.1Components to be considered 89 C.4.2Areas to be considered 91 C.5Actions . 92 C.5.1General . 92 C.5.2Action cycles . 92 C.6Global analysis 93 C.6.1General . 93 C.6.2Flexibility 94 C.6.3Boundary conditions 95 C.6.4Boundary conditions for pipe systems wi
12、th single use compensators (SUCs) . 98 C.7Calculation of stresses . 101 C.7.1General . 101 C.7.2Simplified procedure 101 C.7.3Cross section analyses, steel 101 C.7.4Straight pipes 103 C.7.5Bends . 105 C.7.6Tees 107 C.7.7Other components 112 ? EN 13941:2009 (E) 4 C.7.8PUR foam and PE casing 115 C.8Fa
13、tigue analysis 116 C.8.1Fatigue strength data 116 C.8.2Fatigue strength data, detailed design . 117 C.8.3Design fatigue lives . 117 C.9Further actions 117 Annex D (informative) Calculation of heat losses . 118 D.1General . 118 D.2Heat loss per pipe pair 118 D.3Insulance of the soil 119 D.4Insulance
14、of the insulation material 119 D.5Insulance of the heat exchange between flow and return pipe 119 Bibliography 120 ? EN 13941:2009 (E) 5 Foreword This document (EN 13941:2009) has been prepared by Technical Committee CEN/TC 107 Prefabricated district heating pipe systems, the secretariat of which is
15、 held by DS. 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 January 2010, and conflicting national standards shall be withdrawn at the latest by January 2010. Attention is drawn to the possibilit
16、y 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 13941:2003. According to the CEN/CENELEC Internal Regulations, the national standards organiza
17、tions 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, Netherlands, Norway, Poland, Portugal, Roman
18、ia, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. ? EN 13941:2009 (E) 6 Introduction The standard has been prepared by JWG1, a joint working group with CEN/TC 267 “Industrial piping and pipelines“. According to the scope from CEN/TC 107: The task of CEN/TC 107/TC267/JWG1 is
19、to specify rules for design, calculation and installation for preinsulated bonded pipe systems for underground hot water networks with pipe assemblies co-ordinated with EN 253, EN 448, EN 488 and EN 489. CEN/TC 107/TC267/JWG1 may also specify rules for functional tests for preinsulated bonded pipe s
20、ystems for underground hot water networks. The basic rules for design, calculation and installation should be based on functional requirements. The purpose of the work is to provide uniform basis for the design, construction and operation of district heating systems, to ensure that the system is rel
21、iable and efficient and safe for the surrounding area, the environment and public health. Joint assemblies for pipe systems dealt with should be co-ordinated with EN 489. This standard takes account of experience acquired, of new knowledge available, of the behaviour of material and of distribution
22、of stresses and allowable deformations and also evolution in installation techniques. When use is made of the standard, the different sections of which it is made up must be interpreted as being interdependent and, because of this, cannot be dissociated. The standard consists of a main part and four
23、 annexes. Depending on the character of the individual clauses, distinction is made in this standard between Principles and Application Rules. The principles comprise: general statements, definitions and requirements, for which there is no alternative, as well as requirements and analytical models f
24、or which no alternative is permitted unless specifically stated. The principles are printed in normal typeface (10 point font). The application rules are generally recognised rules, which follow the principles and satisfy their requirements. Application rule: The application rules and comments to pr
25、inciples and application rules are printed in a 8 point font. This is an application rule. It is permissible to use alternative design rules from the application rules given in this standard, provided that it is shown that the alternative rule accords with the relevant principles and it is at least
26、equivalent with regard to the resistance, serviceability and durability achieved by the system. Annex A is part of the standard (principles). Annexes B, C and D have status as application rules. ? EN 13941:2009 (E) 7 This standard contains a number of requirements aimed at ensuring the sound executi
27、on of distribution networks for district heating. To the extent possible, the requirements specified in this standard are functional requirements. The requirements and regulations contained in this standard should be assessed and applied in compliance with the intentions of the standard and in due c
28、onsideration of the development taking place in the field it concerns. It is therefore assumed that the user of the standard has the requisite technical insight and that the user of the standard has adequate knowledge of legal and other external regulations that are of consequence to the practical a
29、pplication of the standard. Special cases may occur within the scope of this standard in which its contents do not cover. An evaluation whether the contents cover shall be made in any specific case where the standard is used. Presently CEN/TC 107 “Pre-fabricated district heating pipe systems“ is pre
30、paring standards for preinsulated flexible pipes and surveillance systems. ? EN 13941:2009 (E) 8 1 Scope This European Standard specifies rules for design, calculation and installation for preinsulated bonded pipe systems for buried hot water distribution and transmission networks (cf. figure 2) wit
31、h pipe assemblies in accordance with EN 253, for continuous operation with hot water at various temperatures up to 120C and occasionally with peak temperatures up to 140C and maximum internal pressure 25 bar (overpressure). Application rule: For larger pipe dimensions and pressures below 25 bar wall
32、 thickness bigger than specified in EN 253 can be required for straight pipes, bends and tees. The principles of the standard can be applied to preinsulated pipe systems with pressures higher than 25 bar, provided that special attention is paid to the effects of pressure. Adjacent pipes belonging to
33、 the network (e.g. pipes in ducts, valve chambers, road crossings above ground etc.) can be designed and installed according to this standard. The standard assumes use of treated water, which by softening, demineralisation, deaeration, adding of chemicals, or otherwise has been treated to prevent in
34、ternal corrosion and deposits in the pipes. This standard is not applicable for such units as: a) pumps, b) exchangers, c) boiler installations, tank installations, d) consumer installations. However, the full functional ability and durability of such units should be ensured in consideration of the
35、impacts from the district heating system and other impacts occurring from the conditions under which they have been installed. Guidelines for product quality inspection and in situ tests of joints are given in Annex A of EN 448:2009, Annex D of EN 253:2009, Annex A of EN 488:2009 and Annex B of EN 4
36、89:2009. Guidelines for welding of polyethylene casing are given in Annex B of EN 448:2009. The estimation of expected life with continuous operation at various temperatures is outlined in Annex B of EN 253:2009. 2 Normative references The following referenced documents are indispensable for the app
37、lication of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 253:2009, District heating pipes Preinsulated bonded pipe systems for directly buried hot water networks Pipe
38、assembly of steel service pipe, polyurethane thermal insulation and outer casing of polyethylene EN 287-1, Qualification test of welders Fusion welding Part 1: Steels EN 444, Non-destructive testing General principles for radiographic examination of metallic materials by X- and gamma-rays ? EN 13941
39、:2009 (E) 9 EN 448:2009, District heating pipes Preinsulated bonded pipe systems for directly buried hot water networks Fitting assemblies of steel service pipes, polyurethane thermal insulation and outer casing of polyethylene EN 473, Non-destructive testing Qualification and certification of NDT p
40、ersonnel General principles EN 488, District heating pipes Preinsulated bonded pipe systems for directly buried hot water networks Steel valve assembly for steel service pipes, polyurethane thermal insulation and outer casing of polyethylene EN 489:2009, District heating pipes Preinsulated bonded pi
41、pe systems for directly buried hot water networks Joint assembly for steel service pipes, polyurethane thermal insulation and outer casing of polyethylene EN 571-1, Non destructive testing Penetrant testing Part 1: General principles EN 583-1, Non-destructive testing Ultrasonic examination Part 1: G
42、eneral principles EN 970, Non-destructive examination of fusion welds Visual examination EN 1289, Non-destructive examination of welds Penetrant testing of welds Acceptance levels EN 1290, Non-destructive examination of welds Magnetic particle examination of welds EN 1291, Non-destructive examinatio
43、n of welds Magnetic particle testing of welds Acceptance levels EN 1418, Welding personnel Approval testing of welding operators for fusion welding and resistance weld setters for fully mechanized and automatic welding of metallic materials EN 1435, Non-destructive examination of welds Radiographic examination of welded joints EN 1712, Non-destructive examination of welds Ultrasonic examination of welded joints Acceptance levels EN 1714, Non-destructive examination of welds Ultrasonic examination of welded joints EN 10