BP has commissioned Parker Drilling to build the world’s largest rig to drill the longest horizontal wells yet completed. The Liberty project, for which the rig is being built, involves drilling over 8 miles to reach pockets of oil offshore from Prudhoe Bay Alaska under the Beaufort sea.
The wells will be drilled from the Endicott satellite pad, which is an artificial island connected to land by a causeway. At stake are over one hundred million barrels of oil which have thus far been beyond BP’s reach.
The massive Liberty drilling rig will be over 240 feet tall and capable of handling three 90′ sections of drill pipe connected together. This will allow for faster trip times in and out of the hole when drilling motors and LWD instruments must be changed. BP will use rotary steerable technology on the world’s largest top drive rig. Special drill pipe, made of a custom alloy especially for the Liberty project, will be used.
To counter the effects of rubbing against casing BP will install special doughnut shaped devices inside the casing to prevent wear on the drill pipe.
BP has experience with other extended reach projects. Their Wytch Field project in England broke records with a horizontal well of 6.6 miles. The Liberty project in Alaska will set new world records for the longest horizontal well.
Extended reach drilling from offshore pads or onshore locations can reduce the overall footprint of oil and gas drilling and help preserve the fragile environment in places such as Alaska. Other benefits include saving millions of dollars by not having to create more artificial islands or place drilling rigs in deep water offshore.
Multiple wells can be drilled from a single pad without having to move the rig more than a few feet. Horizontal drilling is opening up new frontiers in oil and gas drilling and has already increased the supply of natural gas in North America to over a century’s worth. Oil and gas from horizontally drilled wells will soon make up the majority of supply from U.S. wells according to the American Association of Petroleum Geologists.
For information on how horizontal drilling technology works see: Horizontal Well Drilling