Mobile Robot for In-Service Solid-State Repair of Pipeline
Internal Cracks
Zhenzhen Yu, Xiaoli Zhang, and Ruidong Fu
Summary: A mobile robot for in-service solid-state repair of cracks formed on the interior
surface of liquid and gas pipelines.
Description: Stress corrosion cracking can occur in the internal walls of both gas and liquid
pipelines as a result of a corrosive environment and tensile stress on a susceptible material.
Pipeline repair or rehabilitation is often driven by considerations of economics, urgency and
engineering approaches. In-service repair is a highly economic strategy since the need to
excavate the pipeline or take the pipeline out of service is precluded. This is particularly attractive
for pipelines serving in hazardous environment (e.g., corrosive, high temperature, pressure or
radiation conditions) and populated areas. This invention of a mobile robot for in-service repair
of cracks formed on metal pipeline internal wall using an innovative solid-state repair technology.
Solid-state repair is advantageous since it can minimize strength loss during the repair process
and prevent defects and property degradation associated with conventional fusion repair.
Main Advantages of this Invention
 Can be used on hard to reach cracks
 Can potentially restore the strength of the pipe and
 Produce compressive surface residual stress to improve cracking resistance
 Removes human operators from repair work in hazardous environment
Potential Areas of Application
 Oil and Gas
 Utility Companies
 Construction
ID number: 16029
Intel ectual Property Status: US provisional patent filed.
Opportunity: We are seeking an exclusive or non-exclusive licensee for implementation of this
For more information contact:
William Vaughan, Director of Technology Transfer
Colorado School of Mines, 1500 Illinois Street, Guggenheim Hall Suite 314, Golden, CO 80401
Phone: 303-384-2555; e-mail: