Petroleum Pipeline Case Studies
Liquid Petroleum Pipeline, Colorado
At a remote in Colorado, a pressure boost station assists in conveying petroleum products from the refinery in the Texas panhandle to the Denver metropolitan area. This pumping station boosts pressure from about 150 psi on the inlet side to about 1300 psi on the discharge side. In 2004 a pipeline rupture a short distance downstream from this station caused a major spill of petroleum product. Following the rupture in 2004, the regulatory agency directed the operator to limit pipeline pressures below a “set-point pressure” of 1095 psi until further notice, and the operator installed a pair of TP-1’s, one on the suction line and one on the discharge line, to monitor and record pressures continuously. Initial data showed transient pressures reaching as high as 1125 psi momentarily during transient events, as is shown in the 4-day graph below where transient events are depicted in red, while normal pressures are in blue.
The operator continued monitoring for 9 months, with Pipetech International assisting in a third-party role in the analysis of data. Adjustments to the operating parameters were made to ensure that the pressure stayed below the set-point pressure at all times, and eventually the pipeline pressures were precisely as required. A sample taken in September 2006 is shown in the 8-day graph below, indicating the pressure reached but did not exceed 1095 psi.
The flexibility of the TP-1 is illustrated
in the 1-hour graph below, confirming that the operating system immediately dropped the pressure within milliseconds when the set-point of 1095 psi was reached.
The data obtained has been used by the pipeline operator to satisfy the regulators and to obtain authorization to raise the set-point pressure … confident that any incursions above the established value will be documented so that corrective action can be taken.