Keyhole Technology

With excavation and restoration expenses costing U.S. natural gas companies more than $1 billion annually, gas system operators are turning to keyhole methods as a way to reduce overall maintenance costs. Currently, excavation and pavement restoration costs are typically 50% less when keyhole technologies are used.

Keyhole technology provides a cost-saving alternative to common repair methods, which often require large “open” excavations, followed by the removal and disposal of unwanted pavements and soils. These conventional practices—usually performed using several large pieces of equipment (backhoes, dump trucks, pavement breakers, etc.) - can account for 80% of the total cost of a repair job.

BENEFITS

• Reduced costs
• Less labor-intensive
• Less invasive
• Fewer equipment requirements
• Reduced traffic disruptions
• Reduced risk of damage to underground facilities
• Improved worker safety
• Quicker repair times
• Less noise

The Concept of Micro-Excavation

Micro-excavation creates a path to the gas main six inches in diameter or less. Special tools are used to:

Locate the utility line using electromagnetic, acoustic or radar sensors.

Cut a core through the road surface using special equipment such as the Minicor TM

Use the micro-excavation tool to clear a space completely around the pipe.

Examine the pipe for overall coating integrity, level of corrosion. wall and coating thick nesses, possible disbondment, pitting, bell-joint location and other visual verifications. Make repairs as needed using special tools.

Back-fill and cement core in place.

The estimated industry annual savings over open excavation for the sole purpose of direct examination of pipelines and mains is $15 million.