BS 545:2006 pdf download – Ductile iron pipes, fittings, accessories and their joints for water pipelines — Requirements and test methods
4 Technical requirements
4.1 General
4.1.1 Ductile iron pipes and fittings
Nominal sizes, thickness classes, lengths and coatings are specified in 4.1.1, 4.2.1, 4.2.3, 4.4 and 4.5 respectively.When, by agreement between manufacturer and purchaser, pipes and fittings with different wall thickness classes, lengths and/or coatings and other types of fittings than those given in 8.3 and 8.4, are supplied with reference to this standard, they shall comply with all the other requirements of this standard.
NOTE 1 Other types of fittings include angle branches, tees and tapers with other combinations DN x dn, draining tees, … The standardized nominal sizes DN of pipes and fittings are as follows: (see EN 805) 40, 50, 60, 65, 80, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1 000, 1 100, 1 200, 1 400, 1 500, 1 600, 1 800, 2 000.
The allowable pressures of ductile iron pipes and fittings shall be as given in Annex A.
NOTE 2 Annexes B and C give respectively the longitudinal bending resistance and the diametral stifiness of ductle ironpipes.
NOTE3 When installed and operated under the conditions for which they are designed (see Annexes D,E and G), ductleiron pipes, fttings, accessories and their joints maintain all their functional characteristics over their operating life, due to theconstant material properties, to the stability of their cross section and to their design with high safety factors.
4.1.2Surface condition and repair
Pipes,fttings and accessories shall be free from defects and surface imperfections which can lead to non-compliance with Clause 4 and Clause 5.
When necessary,pipes and fittings may be repaired,for example by welding,in order to remove surfaceimperfections and localized defects which do not extend through the entire wall thickness, provided that :
— the repairs are carried out according to the manufacturer’s written procedure;
– the repaired pipes and fittings comply with all the requirements of Clause 4 and Clause 5.
4.1.3Types of joints and interconnection
4.1.3.1 General
Rubber gasket materials shall comply with the requirements of EN 681-1, type WA. When materials other thanrubber are necessary (e.g. for flanged joints), they shall comply with the appropriate European Standard or, whereno European Standard exists, the appropriate lnternational Standard.
4.1.3.2Flanged joints
Flanges shall be constructed in such a way that they can be attached to flanges whose dimensions and tolerancescomply withEN 1092-2.This ensures interconnection between all fianged components (pipes fittings, valves..) ofthe same PN and DN and adequate joint performance.
Bolts and nuts shall comply as a minimum with the requirements of EN ISO 4016 and EN ISo 4034, grade 4.6.when applicable, washers shall comply with EN ISO 7091.
Although it does not affect interconnection, the manufacturer shall state in his catalogues whether his products arenormally delivered with fixed flanges or adjustable flanges.
NOTEFlange gaskets can be one of those given in EN1514.
4.1.3.3 Flexible joints
Pipes and fittings with flexible joints shall comply with 4.2.2.1 for their spigot external diameter DE and theirtolerances.This offers the possibility of interconnection between components equipped with different types offlexible joints.In addition,each type of flexible joint shall be designed to fulfil the performance requirements ofClause 5.
NOTE 1 For interconnection with certain types of joints operating within a different tolerance range on DE,themanufacturer’s guidance should be follawed as to the means of ensuring adequate joint performance at high pressures (e.,g.measurement and selection of extemal diameter).
NOTE2 For interconnection with existing pipelines which can have external diameters not in compliance with 4.2.2.1, themanufacturer’s guidance should be followed as to the appropriate means of interconnection (e.g. adaptors).
4.1.4Materials in contact with water intended for human consumption
Ductile iron pipes fittings and their joints include several materials given in this standard. When used under theconditions for which they are designed,in permanent or in temporary contact with water intended for humanconsumption, ductile iron pipes, fittings and their fjoints shall not change the quality of that water to such an extentthat it fails to comply with the requirements of national regulations.