Passage through China

When the word ‘inspection’ is used to describe a project, many people envision a solitary event. But this is rarely the case in the pipeline industry, and it couldn’t be farther from the truth for PII’s recent PetroChina-Beijing Gas project.

The job included metal-loss and calliper inspections of multiple pipeline segments totalling more than 900 km. We worked between September and December 2006 in extreme temperature and weather fluctuations, in remote areas with rugged terrain and little or no infrastructure for equipment transport or crew/tech support. We errected makeshift workshops in tents for tool assembly, calibration, control and data analysis. We also maintained full ATEX safety standards at all times.

“Everything we do pushes a technological boundary of one kind or another” said PII Project Manager David Willis. “The core idea is always information quality, and that depends on a combination of the tools and the people who use them.”

Pre-mobilization

Being in such remote areas, pre-emptive planning was critical to the program’s success. Prior to mobilization, a senior PII engineer travelled through China to evaluate all the inspection sites, identify potential problems, modify launch/receive plans and ensure that the right equipment would be ready for day one.

Troubleshooting

Even so, this type of work comes with its fair share of surprises. The calliper tool developed electronics difficulties near the end of its second run. This threatened the entire project timeline since the MFL tool couldn’t run without a risk assessment of the pipeline geometry. So we readied a back-up profile tool to ensure the pipe could accommodate the MFL tool, and then ran a successful metal-loss inspection. But it wasn’t time to move on yet – we still needed a complete calliper report for dent anomalies.

PII’s field crews are always supported by a worldwide network of technicians and engineers. So, while all this was on-site troubleshooting proceeded, our North American tech team had prepared new calliper electronics and delivered them overnight from Canada to China. Once the MFL inspection was done, the repaired calliper tool was successfully run through the line to complete the requirements for that segment.

Results

Despite a few other surprises and harsh conditions, the crew forged ahead. More than 30,000 metal-loss anomalies were detected and characterized with excellent data quality; calliper results were of a similarly high standard. The complete and combined data sets were approved for subsequent risk assessment and remediation planning. Little time was lost and all inspections were completed without re-running any tools in any of the 900 km of pipeline.

Keeping an ear to the ground

Southern Star Central Gas Pipeline is the largest natural gas network operator in the central United States. The company operates 6,000 miles of pipeline in four states with annual throughput of 293.3 Bcf. It was also the first North American pipeline operator to install ThreatScan™ as part of its pipeline integrity management program.

ThreatScan is an innovative, real-time, 24/7 monitoring system from GE’s PII Pipeline Solutions business. It provides pipeline operators with a cost-effective means of guarding against safety and environmental hazards. ThreatScan quickly and reliably locates – and even anticipates – third-party strikes and determines their severity. The system uses real-time acoustic signal acquisition, not model-based projections, and is supported by PII’s advanced software and skilled analysts to provide around-the-clock security.

High-risk area

On average, in the United States, there is one delayed failure every 33 days resulting from previously unreported third-party damage. Traditional identification techniques are challenging to implement in a cost-effective manner and frequently deliver unreliable results in terms of both detection capability and response time.

Of key concern to Southern Star was a 13-mile segment running through a highly populated area of Wichita, Kansas. The northern Wichita area is experiencing a great deal of urban expansion, with construction encroaching upon Southern Star’s nearby 16-inch, natural gas pipeline. Half the segment is in a High Consequence Area with schools and hospitals, etc., and 75% is in a Class 3 zone.

In 2006, there were 1,400 one-calls on the segment and two near misses for which there were no notifications at all. With new IMP procedures, Southern Star would have had 1,200 encroachment forms or line markings. Of course, this was all before Southern Star installed ThreatScan to reduce the cost of false alarm responses while increasing public and asset safety.

A safer situation

“ThreatScan is proving to be everything we thought it was and much more” says Kevin Philips, Wichita district operations director for Southern Star. “ThreatScan will help us improve safety and reliability for our customers and the Wichita community.”