API TR 17TR2 pdf download.The Ageing of PA-11 in Flexible Pipes 2 The Ageing of PA-11 2.1 BACKGROUND The main ageing concern regarding PA-11 in ßexible pipe applications, in the absence of oxygen in the bore ßuids, is the effect of water at elevated temperature. The hydrolysis reaction breaks the polyamide links within the polymer, and leads to embrittlement of...