The Application of a Fiberglass Liner in Well Tubing as Cost Effective Material Option in High Velocity Production Wells

Abstract

This paper describes Eni's experience in the application of a Fibreglass liner used as a corrosion barrier in well tubing and the tests performed in high erosion conditions. Liner is made of a Glassfibre Reinforced Epoxy (GRE) resin, inserted in Carbon Steel tubing used in both oil production and water injection wells. Following many successful experiences in these applications, Eni decided to look at what additional requirements would be needed to prove GRE as an alternative material to high grade Corrosion Resistant Alloys (CRA's) for installation in high velocity gas wells. The GRE liner was selected as cost effective alternative to high alloyed materials starting from 2005, where GRE was successful in reducing onshore workover costs and extending the life of Carbon Steel tubing in oil producer wells with high CO2 and water cut, to the more recent installation offshore Norway in Water Injection wells where due to high corrosiveness of the injection fluid. The paper will summarise the testing and the appalication range of GRE in corrosive CO2 and H2S environments and also, through collaboration with Milan Polytechnic, the high flow direct impact erosional testing, utilising a continuous flow loop and nozzle directed solids impingement testing system. Various impinging angles, times and velocities were used during the testing. The results showed GRE to have a good resistance to the solid particles erosion in comparison to the similar tests carried out on Inconel Nickel Alloy material and confirms the potential use of GRE as a corrosion resistance material when combined with Carbon Steel tubulars and alternative to high CRA materials in producer wells. Together with economic evaluations, the paper presents the characteristics of the GRE technology, the acceptable range of field conditions and will highlight feedback for the sites it has been applied.