First Look: New Method To Monitor Curing Of CIPP Installations

By Jeff Griffin, Senior Editor | November 2011, Vol. 66 No. 11

Pipeline Renewal Technologies is introducing an innovative method for monitoring cure temperature of cured-in-place-pipe (CIPP) liner installations.

The VeriCure process uses a new patent-pending approach called micro-zone thermosensing (MZT) which segments the full length of a CIPP liner into narrow zones and monitors the average temperature of each zone to determine when the cure threshold has been attained and when post-cure cool down periods have concluded.

“Liner cure is a complex and dynamic process that, until now, has been monitored with rather primitive technology,” said Jason Wells, VeriCure product line manager. “Liner failure has been a great source of pain for contractors, simply because it has been impossible to verify a comprehensive cure using available technology, and because the cost of rectifying failures is so great.”

Wells said MZT delivers the data necessary to control and document the curing process. This has great implications for the productivity of relining contractors and for the longevity of the infrastructure cities are paying them to rehabilitate.

The technology under the VeriCure trade name became available to relining contractors on a lease basis on Oct. 1, 2011.

“Existing methods for monitoring CIPP cure temperature overlook large regions of the liner,” said Wells. “With the most basic method, each end of the liner is checked with a thermal imaging gun or handheld thermocouple. The assumption is if temperature requirements are met at the ends, they also are met along all points between. However, our field tests have demonstrated quite the opposite.”

Accuracy
Wells said available alternatives to capture date include embedding temperature sensors between the liner and host pipe, but that accuracy of information can be limited because only point measurements are taken, and often at intervals too great to capture a comprehensive temperature profile. Cost and susceptibility to punishing environments has limited industry acceptance, he added

“VeriCure,” said Wells, “uses patented technology to capture accurate temperature data over long distances that already is used in oil exploration, aeronautics and other mission-critical applications. The ability of this technology to monitor CIPP cure temperature has been proven through field trials with very high success rate.”

Wells explains the process: