Enhanced Life Cycle Costing Approach to Tubing Material Selection - New Cost and Revenue Drivers Identified from Experience with Non-Metallics Downhole

Abstract

Abstract ISO 15663 Lifecycle cost (LCC) analysis principles are commonly applied to evaluate the viability of downhole tubing materials. This includes the initial CAPEX, operating or maintenance OPEX, Replacement costs and Revenue impact of tubing failure. Increased implementation of Glass Re-informed Epoxy (GRE) Lined tubing has provided significant evidence of flow assurance benefits of the system. This paper will present a modern adaptation of LCC analysis based on operator data and quantification of these benefits and savings. With over 100,000 GRE Lined completions worldwide there are numerous reported cases of flow enhancements and savings besides corrosion mitigation. The paper is based on extensive research of data collected with agreement from operators representing cost savings or additional revenue that can be factored into LCC analyses with a fair degree of accuracy. Overall operational savings that operators have derived from flow assurance benefits of GRE Lined Tubing, such as improved thermodynamics, scale mitigation, reduced pressure drop, etc. are substantiated using field data from downhole logs, analysis of produced fluids and inspection of retrieved GRE Lined tubing. Operators have reported higher temperature at well head in Oil Producers after steel tubing was replaced using GRE Lined Steel tubing. This has been associated with savings in separation costs at the surface. There are several reports of higher flow rates and reduced pressure drop across GRE lined tubing which translates to higher injectivity or production. Operators have numerous references of improved and stable flow rates for longer durations when compared to bare steel tubing due to the mitigation of carbonate scale deposition which would impact flow dynamics. Such cases represent significant improvements to production efficiency and, consequently, the overall return on investment in the asset. The findings of research on multiple operator flow enhancement case references, while implementing GRE Lined Tubing, are illustrated graphically to represent savings and/or additional revenue in comparison with graphical representations of traditional LCC calculations models based on ISO 15663 key drivers i.e. CAPEX, OPEX, Revenue Impact and Replacement Costs. It is anticipated that this paper will influence a paradigm shift that guides operators to consider the impact of flow enhancement, improved thermodynamics, improved injectivity and/or production, simplification of surface facility requirements and other fringe benefits, in addition to CAPEX, OPEX and Revenue, while evaluating the LCC of tubing material alternatives.