【正文】 C. Any damage to the lining shall be detected immediately after impact in accordance with . Resistance to ovalization The test shall be carried out on a pipe section 500 mm ? 20 mm long, cut from the pipe barrel. The pipe section shall be placed on a support approximately 200 mm wide and 600 mm long, having a V shape with an angle between 170176。C (+/–2 176。. Performance tests Performance tests are carried out once after selection of a lining material and an application process. They shall be carried out again for a new lining material and when a significant process parameter is changed. Chemical resistance The chemical resistance of the lining is tested by immersion in two different fluids. Immersion test in deionised water The immersion test in deionised water shall be performed on a detached specimen of polyurethane lining, approximately 1 mm in thickness, produced and cured in a similar way to the pipe lining. The dry specimens shall be weighed, then immersed for 100 days in a tank of deionised water at 50 176。 its requirements will be introduced in this standard when pleted. 7 Test Methods Routine tests The following routine tests shall be carried out to control the lining production process in order to obtain a lining of high and stable quality. Surface preparation The blasted surface of the pipes and fittings shall be checked visually for pliance with preparation grade Sa of ISO 85011. The surface roughness Ra shall be checked in accordance with ISO 85031. Appearance and continuity The appearance of the finished lining shall be checked visually. Lining thickness The thickness of the lining shall be measured with nondestructive instruments (. based on magic or electromagic principles) which have a measuring accuracy of ? 2 % and an automatic statistic evaluation. A minimum of 10 measurements evenly distributed over the circumference at each end of the pipe (between 100 mm and 300 mm after the entrance) shall be carried out prior to the calculation of (Xmean – 2?). Pipe ends The pipe ends are tested visually and with appropriate metering gauge. Repairs Repairs have to be carried out according to the manufacturer’s written instructions and then subjected to visual inspection. All repairs shall subsequently meet the non porosity test requirements. Marking The marking of the finished lining shall be checked visually. Non porosity AC or DC devices with a voltage defined in and conductive rubber test electrodes are required as test instruments for testing the polyurethane lining. 12 BS EN 15655:2020 EN 15655:2020 (E) During the measurement, the test electrode shall be in contact with the surface of the lining, since any significant air gap would falsify the result. The presence of faults can be detected by the noise of the arcing spark or by signals emitted by the instrument. Hardness The test shall be carried out directly after production on the lined pipe after it has attained the ambient temperature between 10 176。C. Adhesion The adhesion shall be at least 8 MPa when tested in accordance with . 6 Performance Requirements Chemical resistance The chemical resistance is determined by the change in weight of the polyurethane lining. When tested in accordance with , the weight increase resp. weight loss shall meet the requirements given in Table 2 when pared to the original weight. Table 2 — Weight changes requirements Property Unit Test method Clause Requirement Mass change after 100 days in deionised water at 50 176。 ? bituminous paint (only for drinking water)。C above the dew point. The surface shall be prepared by grinding (only for pipes) and grit blasting and be in pliance with level Sa of ISO 85011 when checked according to . The surface roughness Ra in accordance with ISO 85031 shall be at least 12,5 micrometers which is equivalent to an anchored profile Rz of 63 micrometers or higher if required by the lining material provider or manufacturer. Finished polyurethane lining Appearance and continuity The polyurethane lining shall be of: ? uniform colour, except the spigot end and the internal socket profile which may be of a different colour and different coating material。 b) it should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulations concerning the use and/or the characteristics of this product remain in force. 5 BS EN 15655:2020 EN 15655:2020 (E) 1 Scope This European Standard defines the requirements and test methods applicable to factory applied internal polyurethane high duty corrosion protection of buried ductile iron pipes and fittings conforming to EN 545, EN 598 and EN 969 for use at permanent operating temperatures up to 45 176。 I S C HES KOM I TEE F 220。cken Anforderungen und Pr252。thodes d39。 English Version Ductile iron pipes, fittings and accessories Internal polyurethane lining for pipes and fittings Requirements and test methods Tuyaux, raccords et accessoires en fonte ductile Rev234。 NO COPYIN G WITHOUT BSI PERMIS SION EXCEPT AS PERM ITTED BY COPYRIGHT LAW BS EN 15655:2020 National foreword This British Standard is the UK implementation of EN 15655:2020. The UK participation in its preparation was entrusted to Technical Committee PSE/10, Iron pipes and fittings. A list of anizations represented on this mittee 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. Compliance with a British Standard cannot confer immunity