The long term development from four artificial islands of this giant offshore field in the United Arab Emirates (UAE) is requiring longer and longer ERD wells. This can only be achieved by drilling higher angle, higher departure and increasing lateral lengths. Horizontal departure ratios have increased from 2:1 to 3:1 and will, before the development has finished approach 4:1. Maximum Reservoir Contact (MRC) lateral lengths at the beginning of the development were planned to average 10,000ft but are already being lengthened to 20,000ft, and beyond. This paper describes the many challenges that have arisen and have been successfully overcome to enable deployment of 6 5/8" horizontal lower completions of lengths up to 20,000ft into wells that are greater than 30,000ft MD. These challenges have been surmounted through the use of proprietary in-house software, leveraging partner resources and global experience, close collaboration between drilling, completion and field development teams, new technology equipment development and deployment methodologies. Several case histories will be presented and discussed at length in this paper. These will focus on specific aspects for each of the wells such as the; high strength liner connections, high load liner running tools, reservoir drilling fluid composition, swellpacker design, use of drillpipe or casing swivels, centraliser type and the effect of dog leg severity in the long reservoir lateral.

This development, predominantly from four artificial islands, of a giant offshore field in the United Arab Emirates (UAE) requires Extended Reach Drilling (ERD) well design including extended length liners in order to reach drilling and geological targets of the field and Maximum Reservoir Contact (MRC) well design that can drastically decrease development costs. Despite drilling challenges during well construction process such as losses in UER, shallow aquifer flows in Simsima, key seating issues in the base of Simsima, wellbore instability in Laffan and Nahr Umr shale, losses in Salabikh and etc. the team has managed to deliver the longest well to date in UAE to a depth of 35,800 feet and has set many ZADCO internal records for drilling performance with no HSE events. Through the use of enabling best practices, lessons learnt and new technologies such as Casing Swivel, Fixed-Bonded non-rotating centralizers and 21 days swell packers, the well was drilled and completed 11.3 days under Authorization for Expenditure (AFE). Several major milestones and records were achieved such as record drilling performance (spud to TD), longest 8 ½" hole section (18,800 feet) with one Bit and Bottom Hole Assembly (BHA), 16" surface hole inclination of 56°, deepest set 9 ⅝" casing to 17,000 feet MD, longest single stage 6 ⅝" liner in the world (total length of 19,004 feet at the time). All well objectives have been achieved. Several technologies were deployed to enable the abovementioned records including the use of Fixed-Bonded non-rotating centralizers in tandem with sacrificial casing swivel.