Quality Control & Inspection
A lining system is only as strong as the seams that hold it together.
As a leading environmental lining company, we ensure that all of the lining we install provides maximum protection to the land and water. We carefully follow the established industry standards for installing and testing geomembrane.
Prequalification Welding and Testing
The wedge welder (or fusion welder) is what we generally use to weld our main production lines on a jobsite. To qualify the welding equipment for use on the field, we run a trial seam in the morning and in the afternoon. We take a small piece of the representative liner and test the seam’s strength by peeling it apart with the tensiometer. The tensiometer tests for both peel strength and shear strength. The welding machine is approved for use once it passes the trial seam testing.
Field Seam Non-Destructive Testing
Air Channel Test
The air channel test is a way to test a long seam without having to physically tear the liner apart. We close off both ends of the air channel and pressurize it to 30 psi. Five minutes later, if we have lost no more than 3 psi, then we consider it a passing test and the seam is approved.
Vacuum Box Test
While the main production seams are created by wedge welding, if we have to repair a liner, we use extrusion welding. We cover the damaged liner with a new piece of liner and use a hot air gun to heat tack it into place. Then we round down the edges and use an extrusion gun (or extruder) to seal the top liner to the bottom liner.
After that, we test the extrusion weld seam with a vacuum box to make sure it isn’t leaking. We apply a soapy solution to a strip of the seam and then place the pressurized vacuum box over it. If no soap bubbles appear, then the area is considered leak-free.
Quality Control Logs
The test results are recorded both in our quality control logs and on the liner itself. The technician who performs the test also marks his initials and the date on the lining. We are committed to following all of these industry best practices because we are passionate about our role in helping protect the environment.
Download our installation manual, which describes the industry guidelines we follow for installing HDPE and LLDPE geomembrane. (PDF, 17 pages)