TAPS Valves
Ongoing program of improvement

Alyeska discovered in 1997 that it had a valve problem. The maintenance service levels on the Trans Alaska Pipeline System’s (TAPS) 176 mainline valves were not standardized and the valves were starting to show their age. More important, the mechanisms that control these and other facility valves were wearing out and requiring more and more maintenance while replacement parts were getting harder to find.

Alyeska came up with a two-part solution. First they launched an intensive program that concluded in 2001 to bring all of TAPS high priority valves up to a known service level. They then developed the TAPS Valve Maintenance Management Plan to standardize the system’s valves and establish routine maintenance procedures that will ensure the valves continue to function properly well into the future.

“The valve maintenance management plan is the control document that tells us how to maintain TAPS valves and it directs us to do it,” said Bill Aus, Alyeska’s valve and contingency repair engineer. “The plan defines the standard to which TAPS must hold itself in order to meet or exceed legal and regulatory standards.”

Under the plan, TAPS valves that do not meet Alyeska’s performance standards either have been or are scheduled to be replaced with standardized, modern valves. To untrained eyes, the upgraded valves look substantially the same. However, they are both safer and more durable than the old valves.

The upgraded valves have higher machine tolerances and some use metal-to-metal seating so that materials will not break loose that could injure workers. Some valve parts are tungsten carbide coated to reduce wear and certain valves have additional automatic lubrication injection ports that simplify and improve maintenance.

A bigger improvement will be the new actuator and operator mechanisms that control the valves.
Their electronic upgrades will enhance future valve operations and allow for automated and/or remote control and self-diagnostics.

“Standardizing valve-related equipment will increase efficiency and safety on TAPS by reducing training and inventory expenses, decreasing the variety of potential problems and increasing maintenance and operations worker familiarity with all of TAPS valves,” said Aus. “It all dovetails perfectly with strategic reconfiguration planners’ efforts to modernize TAPS.”

A big step toward implementing the valve maintenance and management plan was accomplished last year when Aus finished the pipeline valve maintenance manual. This document details virtually everything there is to know about TAPS pipeline valves and how workers maintain them.

"The valve program has significantly improved external confidence in Alyeska's valve integrity,” said Aus. "Having one document control valve-related decisions leads to TAPS-wide standards that improve safety and reliability and reduce operations and maintenance costs. It just makes sense.”