3-layer-polyethylene (3LPE) corrosion protection coatings play a significant role in the overall performance, integrity and lifetime of steel pipelines. Over the years the properties of such 3LPE systems have been steadily improved. During the installation in the field, the coated pipes are welded to each other; a field joint (FJ) is performed. This is the area with the most detected problems after some years of operation. The majority of field joints are done by shrinksleeves or cold applied tape with rather low requirement level. To ensure the best safe performance level of the pipeline protection, the performance of the coating and the FJ should be similar. A chain is as strong as its weakest link....

This presentation is to introduce a novel PE based FJ coating technology which was developed with the aim to fulfil the level of the minimum requirements of the factory applied coatings. An overview on the machinery and application, on the specially designed PE based material and the achievable properties, especially in relation to the line coating will be presented. Practical experience will be shared with the audience by a report about the Finnish Gasum pipeline project in Mäntsälä on a 500mm gas pipeline.