BS ISO 13470:2012 pdf free download.Trenchless applications of ductile iron pipes systems — Product design and installation.
This International Standard specifies the requirements, test methods and installation technologies applicable to ductile iron pipes used in trenchless applications:
— to convey water or wastewater;
— operated with or without pressure.
This International Standard applies to pipes, fittings and accessories cast by any type of foundry process or manufactured by fabrication of cast components, as well as corresponding joints, of a size range DN 80 to DN 2 600 inclusive.
2 Normative references
ISO 2531, Ductile iron pipes, fittings, accessories and their joints for water applications;
ISO 7186, Ductile iron products for sewerage applications;
ISO 8180, Ductile iron pipes- Polyethylene sleeving for site application;
ISO 10804, Restrained joint systems for ductile iron pipelines-Design rules and type testing;
EN 14628, Ductile iron pes, fittings and accessories-External polyethylene coating for pipes-Requirements and test methods;
EN 15189, Ductile iron pipes, fittings and accessories-External polyurethane coating for pipes-Requirements and test methods;
EN 15542, Ductile iron pipes, fittings and accessories-Externa cement mortar coating for pipes – Requirements and test methods.
3.1 allowable angular deflection
angular deflection that a joint between two components can safely withstand in service under the allowable operating pressure (PFA).
3.2 allowable pulling force
maximum pulling force that can be applied on a string of pipes during laying by horizontal directional drilling. pipe bursting or casing technologies.
3.3 allowable pushing force
maximum pushing force that can be applied on a string of pipes during laying by pipe jacking, pipe bursting or casing technologies.
3.4 clay mineral, primarily montmorilonite, with high swelling properties, which forms the primary component in drilling muds used in horizontal directional drilling technology.
4.2 Horizontal directional drilling(HDD)
4.2.1 General
HDD is a steerable trenchless method of installing underground pipes along a prescribed bore path by using used where trenching or excavating is not practicable. It is suitable for a variety of soil conditions and roy a surface launched drilling rig, with minimum impact on the environment (see Figure 1).Directional bori including road and river crossings.
he sequence of operations is generally divided into three successive steps.
4.2.2 First step- Pilot bore
The pilot bore is the first step in producing a bore, running from the starting point to the arrival pit, and is driven under steered control by a drilling head at the tip of a drilling string.