Field joint coating of steel pipes
The ever-expanding oil and gas pipeline network around the world is nowadays mainly built by using plastic coated steel pipes because the plastic coating gives great life expectancy and superior mechanical and corrosive resistance to the pipe.
Uponor Infra and Borealis have developed a new –patent applied–system for coating of field joints. The system is based on Borealis newly developed Borcoat™ material and the Wehocoat machine developed by Uponor Infra Technology.
Wehocoat device is ideal equipment for extruding the field joint with molten polymers to achieve a joint at site as good as the factory coating and definitely operational in the field, all weather conditions taking into account.
The complete Wehocoat package includes a specially designed, four-wheel drive truck which carries a crane suitable for moving the light automated robot onto the pipe. The specially developed polymer Borcoat™ME3000FC in pellet form is fed into an extruder on the truck which plasticizes it and refills the robot's material-buffer cylinder whilst moving from one joint to the next.
The basic idea is that the welded joint area is blasted clean, induction heated and then powder epoxy is applied followed by a layer of molten plastic using the specially designed robot. The Wehocoat robot carries out all stages of the work completely automatically.
The coatings made by the Wehocoat machine are extremely hard wearing and as durable as the pipe coating applied in the factory. The quality of the surface of the joint is better than any other joint coating This field joint coating method can achieve a joint at site conditions which can fulfill the minimum demands as stated in the ISO - FDIS 21809-1 for a factory coated steel pipe and is defined according to ISO 21809-3 section 5E.