Description

This Standard provides requirements for use by purchasers and manufacturers of steel pipeline systems, for external protection of pipeline systems against corrosion, by a method of annular or laterally extruded layer of high-density polyethylene over a sealant layer. Operating temperatures are in the range of -20°C to 55°C.

Scope

This Standard specifies requirements for external protection against corrosion of pipeline systems, whereby a sealant layer is interposed between the pipe and the extrudate of highdensity polyethylene, applied using annular or lateral extrusion techniques, to comprise the external coating.

Materials complying with this Standard are intended for use where the pipe temperature during operation is in the range of -20°C to +55°C. Guidance is provided on selection and testing of the coating where elevated temperatures may be encountered during storage, stockpiling or construction.

The performance of the coating at high and low temperatures may not be as reflected by tests carried out at ambient temperatures. For example, mastic creep and penetration, and coating system peel strength and cathodic disbanding resistance may not be as at ambient temperatures.

The coating is intended for use in applications where it is not subject to weather or ultraviolet light exposure. A safe period of 12 months of weather exposure after manufacture is allowed for completion of the installation of the pipeline system.