Alyeska restarts line after maintenance

Alyeska Pipeline Service Co. said July 17 that it safely restarted the Trans Alaska Pipeline System following a planned maintenance shutdown of the 800-mile oil pipeline system which runs from Alaska’s North Slope to Valdez.

Major projects included work at Pump Station 4 south of Prudhoe Bay and at Pump Station 11 (now the Glennallen response base) near Glennallen.

At Pump Station 4, the company said, a 48-inch diameter 62,000 pound valve and a 36-inch diameter 26,000 pound valve used to redirect the flow of crude oil inside the pump station were replaced as part of planned maintenance. The valves are part of the system that enables the station to receive and launch inline cleaning and inspection devices known as “pigs.”

Near Glennallen, at the Pump Station 11 site, piping to accommodate a pump station was installed as part of original construction but the pump station itself was never built. During the shutdown, the legacy pipe and valves were replaced with new “straight line” pipe to eliminate the potential for corrosion in the unused “dead leg” piping.

Other work included maintenance work on several mainline valves and work at several pump stations and the Valdez Marine Terminal, including valve maintenance, annual electrical system maintenance and inspections, and modifications to the LEFM (leading edge flow monitoring) equipment at pump stations 3, 8 and 11.

Mike Joyner, Alyeska’s senior vice president for operations, called the work “an outstanding example of flawless operations and maintenance and a fine demonstration of TAPS teamwork.” Alyeska said the major shutdown, the only one this year, was set to last 36 hours and was completed ahead of schedule.

Alyeska operates the 800-mile trans-Alaska oil pipeline for owner companies BP Pipelines (Alaska), ConocoPhillips Transportation Alaska, ExxonMobil Pipeline Co., Unocal Pipeline Co. and Koch Alaska Pipeline Co.

—Petroleum News