Deepwater cement design optimized for record-length expandable liner in Gulf of Mexico

摘要

Solid expandable tubulars offer the industry an excellent solution for gaining a pipe size for completions when well conditions necessitate the setting of additional drilling liner. For operators to take full advantage of expandable liner technology, a successful cementing job is critical. Without a successful cement job, the expandable installation itself can be jeopardized by complicating and, in some cases, preventing remaining well operations from moving forward. For this reason, a well-engineered approach to cementing is vital to obtaining a good cementing result. The engineering needs to begin with the drilling of the hole section and continue through leaving acceptable hole conditions for the liner installation and eventual cementing. Results obtained from this case history provided the opportunity to reach the main zones to be drilled and evaluated and still obtain a satisfactory completion program. Conclusions drawn from this case history and other installations performed are: Proper window preparation and hole cleaning before running expandable casing is recommended. Determine placement time needed based on liner length and expansion cycles required. Perform temperature simulations to determine BHCT and heat-up rate for thickening time required. Prepare a schedule for TT test based on cycles required for motor shutdown (on/off schedule). Perform proper lab testing based on this modified lab schedule for both TT and compressive strength. Perform lab testing to obtain optimum spacer and surfactant design for synthetic-based mud system. Perform engineering simulations using cementing software for proper ECD management during cementing operations. Deliver these designs to the well site with a plan for placement using offshore equipment capabilities. Using these practices has led to excellent results, delivering better wellbore architecture and opportunities to drill deeper wells in deepwater.