New Developments in Dual‐Layer FBE for Pipe Coating

Over the past twenty years Fusion‐Bonded Epoxy (FBE) and three‐layer Polyolefin coatings have established themselves as the dominant coating Systems for oil and gas pipelines worldwide. Both types of coating have specific advantageous properties in their role to protect the steel substrate from corrosion. However, both Systems also have drawbacks which limit their complete acceptance. FBE as a standalone System has excellent adhesion and cathodic disbondment resistance but needs careful handling to avoid excessive damage. On the other hand 3‐layerPolyolefin Systems may be more damage resistant but also may shield an applied cathodic protection current giving rise to potentially serious disbondment problems. In addition many specifications for 3‐layer Polyolefin pipe coatings specify FBE film thicknesses that are insufficient for long‐term corrosion protection. An attractive and cost‐effective solution to these drawbacks is the use of a Dual‐Layer FBE coating System. This paper presents new developments in such a coating with significantly enhanced flexibility at low temperatures down to ‐30oC and excellent compatibility with cathodic protection. Dual Layer FBE coatings are now available with a range of specially engineered FBE topcoats, giving a choice of outstanding flexibility and impact resistance, gouge and damage resistance, or anti‐slip properties for concrete jacketing on sub‐sea pipelines. The application process for Dual‐Layer coatings is the same as for stand‐alone FBE coatings and repair of damage is similarly straightforward. Dual‐Layer coatings are also easily applied in the field to girth welds ensuring that a pipeline can be protected with a completely uniform coating along its length.

کلیدواژه ها:

FBE ، Dual Layer ، Gouge ، Flexible ، 3LPO