NH Penstock Pipeline Replaced With Fiberglass Pipe

November 2008 Vol. 63 No. 11

The HOBAS FWC coupling joint utilized on this project was a pressure joint. It is commonly used in direct bury application and also for above ground installations such as penstocks. It is a structural filament wound sleeve over wrapped and mechanically locked to an internal full-faced elastomeric membrane. The sealing design includes both lip and compression elements so the joint is suitable for both non-pressure and pressure service up to 250 psi. “In our case, we air tested each joint after assembly with a 10 psi air test. None of the joints leaked. Once the line was in operation, we were required to visually inspect each and every joint for a sign of leakage and there was none,” explained Porter.

JML Trucking and Excavating of Errol, NH, was the installation subcontractor for CCB. Butch Lane echoed the general contractor’s sentiments, “The joints are really tight. We were able to put PSNH online two weeks ahead of schedule and that makes them happy.

“At the end of the project, it was found to be approximately seven times cheaper per foot to utilize the fiberglass pipe option partially backfilling the penstock than to support it above ground,” summarized Martin. Hydraulic advantages and longevity of the line will also provide life-long savings.

Hobas Pipe USA, (800) 856-7473 or (281) 821-2200, www.hobaspipe.com
Kleinschmidt Energy & Water Resource Consultants, (207) 487-3328, www.kleinschmidtusa.com