Micro-Excavation Technology Development

Gas Technology Institute (GTI) is developing a micro-excavation system to access buried gas facilities through openings as small as two to three inches in diameter. The initial application for micro-excavation is for the direct examination of gas pipelines to determine the condition of the pipe and pipe wrap. Future applications may include tracer wire repairs, general pipe maintenance, and leak repairs.
Background:
U.S. natural gas companies annually spend more than $1 billion in excavation and restoration costs. The standard technique for accessing pipes involves excavation through three-feet-by-four-feet bell holes, followed by appropriate restoration~a procedure that can cost $1,000 or more per hole. Additional factors frequently add to this cost, including often-required pavement cutback or curb-to-curb re paving. In addition, backfill materials can settle over time, causing callbacks for additional street repairs.
Currently, utilities are reducing operating costs through the use of keyhole excavation, a procedure that makes a circular cut in the pavement with a diameter of about 18 inches. With micro-excavation technologies, the size of excavations required to access a buried gas pipe can be further reduced to two to three inches. This will further reduce the overall cost of excavation and restoration activities.
Small-hole technology has evolved significantly over the past five years. Currently, equipment exists to locate underground utilities, core street surfaces, vacuum excavate down to buried infrastructure, perform a variety of repair/restoration tasks, and restore the road surface.
The Concept:
With micro-excavation techniques, paths to the gas main (six inches in diameter or less) are created with special tools.
Researchers are working to develop a system to provide a complete circumferential space around the pipe to allow inspection at the area of interest. In addition to this new excavation technology, development of new inspection tools to examine the pipe through smaller excavations. These new inspection technologies would be used to determine overall coating integrity and level of corrosion. A variety of sensors (including fiber optics, ultrasonic transducers, and magnetic thickness gages) could be used on the pipe via the micro-hole to measure wall and coating thickness and possible disbondment and pitting. Underground viewing applications include cast-iron bell-joint location and various other visual verifications.
Benefits:
Micro-excavation offers many significant benefits, including reduced contracting costs, excavation, and restoration costs. With the size of the hole being reduced, traffic disruptions decrease and relations with municipalities improve. Since the size of the excavation is greatly reduced, the risk of interference with other underground lines drops significantly. Liabilities and personal injuries will diminish due to the decrease in the use of heavy equipment, such as jackhammers and backhoes.
The estimated industry annual savings over open excavation for the sole purpose of direct examination of pipelines and mains is $15 million. Additional savings will be realized as the use of micro-excavation is expanded to include other gas industry operations and maintenance activities.
Status:
Micro-excavation development at GTI is being supported by Operations Technology Development, NFP. and GTI's Sustaining Membership Program. Through this effort, researchers are evaluating and developing tools to accomplish service abandonment, anode installation, cast-iron joint sealing, and direct examination through micro-holes. It is anticipated that once these applications are proven, the technology can be expanded to provide leak repairs, pipe coating repairs, tracer wire repairs and installations, and service line installation.

For more information:
www.gastechnology.org

State-of-the-Art Technology has Transformed
the Oil and Natural Gas Industry

The Oil and Natural Gas Industry has developed and applied an impressive array of innovative technologies to improve productivity and efficiency, while yielding environment benefits. According to the U.S. Department of Energy, "the petroleum business has transformed itself into a high-technology industry."

State-of-the-Art technology allows the industry to produce more oil and natural gas from more remote places ~ some previously unreachable ~ with significantly less adverse effect on the environment. Among the benefits: increased supply to meet the worlds growing energy demand, reduced energy consumption at oil and natural gas facilities and refineries, reduced noise from operations, decreased size of facilities, reduced emissions of pollutants, better protection of water resources, and preservation of habitats and wildlife.

This progress is documented in a 1999 DOE report, "Environmental Benefits of Advanced Oil and Gas Exploration and Production Technology" that states, "...innovative E & P approaches are making a difference to the environment. With advanced technologies, the oil and gas industries can pinpoint resources more accurately, extract them more efficiently and with less surface disturbance, minimize associated wastes, and ultimately, restore sites to original or better condition."

For example, researching fuel cells that may power the vehicles of tomorrow with greater efficiency and less environmental impact. Investigating ways to tap the huge natural gas resources locked in gas hydrates. Gas hydrates are common in sediments in the ocean's deep waters where cold temperatures and high pressures cause natural gas and water to freeze together, forming solid gas hydrates. Gas hydrates could be an important future source of natural gas for our Nation.

Technological advances such as these are making it possible for the oil and natural gas industry to grow in tandem with the nations energy needs while maintaining a cleaner environment. The industry is committed to investing in advanced technologies that will continue to provide affordable and reliable energy to support our current quality of life, and expand our economic horizons.

For more Information:
www.api.org