The plastics joint venture project between ADNOC and Austrian chemical and plastics manufacturer, Borealis demonstrated their steel pipeline rehabilitation solution at the Arabplast Exhibition in Dubai this week.
Internal corrosion of steel pipelines is a major hazard to oil and gas companies due to the high level of environmental costs and implications of spillage of oil or contaminated water. Regular replacement of the pipelines leads to high costs for the operator.
Companies such as Kuwait Oil Corporation (KOC), which is suffering from an increasing presence of hydrogen sulphide, are seeking solutions to internal corrosion. One option is to use “close-fit” internal lining of polyethylene pipes which will significantly extend the life of the original pipeline. This is equally true for flow lines and water injection lines, which could be internally protected in the same way to increase their service life.
Borouge has allied with plastic pipe producer Kuwait International Advanced Industries (KAI) and Anti-corrosion Protection Systems (APS), a specialist relining contractor based in Dubai, to seek a solution by approaching the Operations Technical Services Division of the Kuwait Oil Corporation (KOC). A ‘tough’ PE100 liner is proposed for an existing steel pipe, which although it has only been installed a relatively short time ago is already showing signs of corrosion.
The new high stress crack resistant PE100 grade from Borouge, BorSafe HE3490-LS-H is applied for the highest security. This material provides a much higher resistance to crack growth than standard PE100 materials, the company claims. In notched pipe testing, the performance is an order of magnitude greater than the 500 hour required by the PE100 specification. Therefore, any defects or scores that are introduced during installation will not develop into cracks, which will cause premature failure of the lining.
The project will commence when a section of an existing steel water injection line is decommissioned and removed from the pipeline and this section is then pigged to remove the considerable amount of sludge and corrosion products that have accumulated in the bore of the pipe. The PE100 pipe will be delivered to the site and the pipe lengths butt welded together by APS and pressure tested prior to insertion.
The pipe will then be inserted into the steel pipe using the well known “swage-lining” close fit insertion technique. In this method the pipe is drawn through a smaller diameter die by a winch, which then pulls the pipe through the host pipe. When the winch is uncoupled, the PE pipe tries to reform to its initial diameter and forms a close fit with the bore of the steel pipe.
