EN 253 - pputruba.ru

1 EUROPEAN STANDARDNORME EUROP ENNEEUROP ISCHE NORMEN 253 January 2009 ICS en 253 :2003 English VersionDistrict heating pipes - Preinsulated bonded pipe systems fordirectly buried hot water networks - Pipe assembly of steelservice pipe, polyurethane thermal insulation and outer casing ofpolyethyleneTuyaux de chauffage urbain - Syst mes bloqu s de tuyauxpr isol s pour les r seaux d'eau chaude enterr sdirectement - Tube de service en acier, isolation thermiqueen polyur thane et tube de protection en poly thyl neFernw rmerohre - Werkm ig ged mmteVerbundmantelrohrsysteme f r direkt erdverlegteFernw rmenetze - Verbund-Rohrsystem bestehend ausStahl-Mediumrohr.

2 Polyurethan-W rmed mmung undAu enmantel aus PolyethylenThis European Standard was approved by CEN on 5 December members are bound to comply with the CEN/CENELEC Internal 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 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 members are 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.

3 Switzerland and United COMMITTEE FOR STANDARDIZATIONCOMIT EUROP EN DE NORMALISATIONEUROP ISCHES KOMITEE F R NORMUNGM anagement Centre: rue de Stassart, 36 B-1050 Brussels 2009 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national No. en 253 :2009: EEN 253:2009 (E) 2 Contents page Foreword .. 4 Introduction .. 5 1 Scope .. 6 2 Normative references .. 6 3 Terms and definitions .. 7 4 Requirements .. 9 General .. 9 steel service 9 Specification .. 9 Diameter .. 10 Wall thickness .. 10 Surface 12 Casing .. 12 Material properties .. 12 Casing properties.

4 13 Polyurethane rigid foam insulation (PUR) .. 15 Composition .. 15 Voids and bubbles .. 15 Compressive strength .. 15 Pipe assembly .. 15 General .. 15 Pipe ends .. 15 Diameter and wall thickness of the casing .. 15 Centre line deviation .. 16 Expected thermal life and long term temperature resistance .. 17 Thermal conductivity in unaged condition .. 17 Thermal conductivity at artificially aged condition .. 17 Impact 17 Long term creep resistance and modulus .. 17 Surface conditions at delivery .. 18 Measuring wires for surveillance systems .. 18 5 Test methods .. 18 General conditions and test specimens.

5 18 General conditions .. 18 Test specimens .. 18 Casing .. 19 Appearance and surface finish .. 19 Elongation at 19 Carbon black dispersion, homogeneity .. 20 Stress crack resistance test .. 20 Polyurethane rigid foam insulation (PUR) .. 21 Composition .. 21 Voids and bubbles .. 21 Compressive strength .. 21 Pipe assembly .. 21 Axial shear strength .. 21 Tangential shear strength .. 23 Shear strength of the pipe assembly after ageing .. 25 Thermal conductivity in unaged condition .. 26 Thermal conductivity at artificially aged condition .. 26 Impact 26 Long term creep resistance and modulus at 140 C.

6 26 6 Marking .. 30 en 253 :2009 (E) 3 30 steel service pipe .. 30 Casing .. 30 Pipe assembly .. 30 Annex A (informative) Relation between actual continuous operating conditions and accelerated ageing test conditions .. 31 Annex B (informative) Calculation of the minimum expected thermal life with operation at various temperatures with respect to PUR foam performance .. 33 Annex C (normative) Calculated continuous operating temperature (CCOT) .. 34 34 Symbols .. 34 Ageing and shear strength determinations .. 34 Calculations .. 35 Determination of the thermal life at different ageing temperatures.

7 35 Adoption to the Arrhenius relation .. 35 Calculated continuous operating temperature, CCOT .. 35 Annex D (informative) Guidelines for inspection and testing .. 37 37 Manufacturer's type test .. 37 Manufacturer s quality control .. 37 External inspection .. 37 Manufacturer's responsibility .. 37 Annex E (informative) Radial creep behaviour of the polyurethane foam (PUR) .. 40 Annex F (normative) Thermal conductivity of pre-insulated pipes - Test procedure .. 41 Scope .. 41 Requirements (EN ISO 8497:1996, Clause 5) .. 41 Test specimen (EN ISO 8497:1996, ) .. 41 Operating temperature (EN ISO 8497:1996, ).

8 41 Types of apparatus (EN ISO 8497:1996, ) .. 41 Apparatus (EN ISO 8497:1996, Clause 7) .. 41 Guarded end apparatus .. 41 Calibrated end 41 Dimensions (EN ISO 8497:1996, ) .. 42 Heater pipe surface temperature .. 42 Test specimens (EN ISO 8497:1996, Clause 8) .. 42 Conditioning (EN ISO 8497:1996, ) .. 42 Dimension measurement (EN ISO 8497:1996, ) .. 42 Surface temperature measurement .. 42 Procedure (EN ISO 8497:1996, Clause 9) .. 42 Test length (EN ISO 8497:1996, ) .. 42 Diameter (EN ISO 8497:1996, ) .. 42 Thickness of casing .. 43 Ambient requirements (EN ISO 8497:1996, ) .. 43 Test pipe temperature (EN ISO 8497:1996, ).

9 43 Power supply (EN ISO 8497:1996, ) .. 43 Axial heat loss (EN ISO 8497:1996, ) .. 43 Test period and stability (EN ISO 8497:1996, ) .. 43 Calculations (EN ISO 8497:1996, Clause 11) .. 43 Thermal conductivity (EN ISO 8497:1996, ) .. 43 Symbols and units (EN ISO 8497:1996 Clause 4) .. 44 Annex G (informative) National A-deviations .. 46 Swedish national legislative deviations on steel service pipes .. 46 Annex H (informative) Main changes from the previous edition of en 253 .. 47 Annex I (informative) Waste treatment and recycling .. 49 Bibliography .. 50 en 253 :2009 (E) 4 Foreword This document ( en 253 :2009) has been prepared by Technical Committee CEN/TC 107 Prefabricated district heating pipe systems , the secretariat of which is held by DS.

10 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 July 2009, and conflicting national standards shall be withdrawn at the latest by July 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 253 :2003. Annex H provides details of significant technical changes between this European Standard and the previous editions.