Abderrazak Traidia

Over the last decade, the deployment of nonmetallic pipes at Saudi Aramco has been exponential and reached an unprecedented level. Reinforced Thermoplastic pipes (RTP) are slowly becoming the product of choice for surface transport of pressurized oil, gas and water systems. Realizing the tremendous benefits that can be realized from lifecyle costs savings, Saudi Aramco has been playing a catalyst role in the RTP market to promote the emergence of new products and new applications. Owing primarily to their corrosion-free nature and competitive lifecycle costs, RTP are now gaining great deal of attention in the development of green energy infrastructure, particualry for hydrogen transport.

Polymeric materials are permeable to gases particularly at high temperature and pressure. The use of RTP to transport pressurized hydrogen raises the natural concern over their ability to limit hydrogen leakage through permeation. In the absence of an industry standard for qualification for RTP in hydrogen service, pipe suppliers draw on the specifications in API 15S where permeation testing is carried out at coupon level (and seldom at pipe level) to assess the permeation barrier performance of the pipe materials. The present work will detail some recent findings in hydrogen permeation testing of different RTP products at different scales. Coupon-level testing was carried out for a combination of liner and pipe wall materials to compare to the barrier performance of different liner materials but also the contribution of the liner to the overall permeation level. Full scale pipe testing was also carried out to compare to coupon-level data and highlight some of the limitations in predicting pipe level behavior from coupon-level testing. The data presented in this work are a first step towards the development of low permeation RTP for hydrogen transport.