Contractor Fixes Failing Cured-In-Place Pipe Lining

Problem:

Lametti & Sons, Inc. has been rehabilitating pipelines and sewers since 1953, and they are CIPP experts. But that doesn’t mean every project is completed without a hitch. “Very cold soil on a 14,000 foot interceptor rehabilitation in southwest Minneapolis caused a ‘soft spot’ near the middle of a run,” explains Project Manager Ross Larson. “It only happens a dozen or so times a year, but when it does, we’re in danger of losing the whole lining.” These soft spots are places where the lining is losing stiffness or adhesion, and sags away from the original pipe. Fixing the individual weak spots without compromising or replacing the entire lining is a major challenge.

Solution:

Lametti & Sons uses inflatable point repair packers from Petersen Products to fix failing pipe linings. “We call them steam plugs,” Larson says. “We inserted a 10-inch plug into the liner and pushed it along until it was centered at the soft spot. Then we inflated it with the same steam truck that we used to cure the liner.” When filled with steam, the reusable packers press out against the lining, returning it to round, and apply heat and pressure where it’s needed to ‘recook’ the lining in place.

Result:

“If we didn’t have these, we’d have to improvise something and it wouldn’t be as good,” Larson says. “Because we don’t have to cut out sections or reline, the steam plugs save us $1,000s every time we use them.”