Performance Evaluation of a Large Bore Expandable Liner Hanger for Field Operations in the Gulf of Mexico

Abstract

Abstract Liner hangers are expected to maintain anchor capability and pressure integrity throughout the life of the well. For deepwater applications where operational expense is considerably higher, liner-hanger performance is essential. Recently, large-bore expandable liner hangers have been scrutinized for sustainability of their bi-directional anchor capability during worst-case discharge scenarios; the importance of this capability also has been reinforced by the Bureau of Safety and Environmental Enforcement (BSEE) requirements. Therefore, since testing of the many possible scenarios is economically prohibitive, it is necessary to use engineering analysis and methods to predict bidirectional anchor capability of large-bore expandable liner hangers (LBELH) under varying conditions. With accurate information, these analytical methods can be used to determine appropriate equipment selection while planning well-construction. The focus of this paper addresses the challenges of evaluating large-bore expandable liner-hanger installations offshore, where daily costs can reach $1.7MM. Predicting performance is challenging, considering the varied physics existing from well to well and the fact that anchor loads at the liner hanger will vary due to downhole conditions that cannot be simulated accurately in laboratory test wells. Varying temperature, effects of earth horizontal stress, hydrostatic pressure, varying parent casing internal/external diameter and wall thickness all affect the anchor capability of the large-bore expandable liner hanger. Given the many varying parameters, finite element analysis (FEA) is required. This paper discusses how FEA was used to estimate LBELH performance for several deepwater well completions in the Gulf of Mexico that required setting in 16-in. medium and heavy-wall target casing. It will also discuss how FEA analysis was used to facilitate liner-hanger development and to secure reliable results. Due to the high cost of nonproductive time during the well construction phase, deepwater operators rely on service providers for reliable solutions that will reduce operational costs. The LBELH was chosen over conventional methods due to high deployment reliability, which can reduce high remediation costs. The case studies presented in this paper will discuss successful job results for an operator that highlight the value offered by numerical simulations in deepwater GOM installations. One of these case studies will review loads applied during setting and post-cementing testing at an operator's well.