Six months after giving pipelines the green light to use high-stress pipelines more widely, the Pipeline and Hazardous Materials Safety Administration (PHMSA) is now highlighting safety concerns with new pipelines operating at 80% of specified minimum yield strength (SMYS).
The concerns are the results of intensified inspections over the past 18 months. Prior to November pipelines could build lines at 80% if they were granted special permits from PHMSA. After the agency published a final rule in November, any pipeline could operate at 80% in a class 1 location — up from 72% of SMYS — without a special permit.
Pipelines pressed to get out from under the special permit requirement because of the huge construction boom and the need to move more gas more quickly, and ostensibly more cheaply, too. Operating at 80% allows pipelines to do just that; but the thinner pipe raises the risk that problems with coating, welding or steel could have bigger repercussions than at 72% of SMYS or lower.
In an interview, Alan Mayberry, director, engineering and emergency support at PHMSA, says inspectors had turned up new pipe that had just been buried, after being inspected by the company, whose coating was problematic. There have been problems with welds, too. He declines to quantify the problems. No enforcement actions have been taken yet. But he explains that “some cases are pending.”
That is the backdrop to the recent public meeting PHMSA held in Fort Worth. Without providing any inspection data prior to the meeting, the agency said the get-together was necessary because it had “identified issues regarding procedures and inspection of pipeline coating, welding, and general pipeline construction practices. Many of the issues required immediate response from operators to avoid affecting long-term pipeline integrity before the pipeline was put into service.”
The Interstate Natural Gas Association of America (INGAA) had already been aware of PHMSA’s concern. It held a “Safety Culture” workshop in Houston on March 23 and a Quality Assurance Quality Control Workshop two days later where several construction issues of concern to PHMSA were laid out. Steve Nanney, project manager, engineering and emergency response at PHMSA, showed slides of scared, gouged and miswelded pipe as examples of the problems PHMSA is finding.
Richard Hoffmann, executive director of the INGAA Foundation, emphasized at the March 25 workshop that the number of miles of new pipeline being built had jumped (2,727 miles/23.2 Bcf/d) in 2007 after three or four years of anemic construction. That increase was maintained in 2008 with FERC approving another 2,139 miles/15.2 Bcf/d with 2,054 miles/15.59 Bcf/d pending for 2009.
Patricia Klinger, deputy associate administrator for governmental, international and public affairs, says the workshop “shows we are very serious, and that there could be a serious problem, especially with all the pipeline building expected in the next 10 years. The point we are trying to make is let’s get it right now.”
Terry Boss, INGAA senior vice president, explains that supply of pipe, construction materials, construction firms and quality-control personnel have had a hard time keeping up with demand.
“Everyone is stretched to the hilt,” he explains. As a result, a lot of new companies have gotten into the pipeline supply and construction business with some of them clearly not being ready to meet the higher safety requirements for 80% SMYS pipelines. This has resulted in defective pipe being supplied, poor welds and other problems which have turned up in PHMSA inspections.
“There have been a couple of hydrostatic test failures,” explains Boss. He notes that the interstates test high-stress lines at between 100-110% of SMYS, which is higher than the operating pressure, so some problems are expected. INGAA is as concerned about these construction problems as PHMSA, not only because of the safety, but because the problems lead to added construction costs as pipelines have to replace bad pipe.