Double-Diameter Upsizing With Pipe Reaming

June 2010 Vol. 65 No. 6
Unusual but effective drill location.

Nowak Construction Co. Inc., Goddard, KSs, was the prime contractor who installed both the reamed and open-cut sections. Manhole replacement was sub-contracted to Stevens Contractors Inc., Salina, and the manhole rehabilitation sub-contracted to Mayer Specialty Services LLC, Goddard, KS. The city of Salina provided the by-pass pumping system for the duration of the project.

Insufficient “stringing” room necessitated fusing the pipe into three sections, each fused into approximately 500-foot lengths that were then pulled into place.

Complications
Considered to be a single pull, continuous installation, the Ditch Witch 7020 HDD drill rig performed as expected, installing at the rate of 50-feet per hour, with pullback and torque pressures kept to the moderate range.”

At 3 a.m. on a very cold and blustery night, a swivel broke, bringing the project to a halt with about 700-feet in place. The crew cut the concrete paving, excavated and shored down to the reamer, replaced the swivel and restarted the installation after a weary 12 hours, resuming at essentially the previous rate of installation to a point approximately 100 feet from completion where pull back and torque pressures rose dramatically until completion.

The reason for the high pressures became evident with a look at the retrieved reamer: the front six to 8-inches of the cutting face was destroyed. Having retrieved a large block of concrete at a service connection containing two-inch steel pipe, perhaps used for reinforcement, is a reminder that regardless of the cause of reamer damage, there will always be problems that will hit your equipment – and wallet.

While recognizing that double diameter upsizing is never easy, the result was a satisfactory and cost-effective installation.

FOR MORE INFO:
InneReam Pipe Replacement System, (316) 794-8898, www.pipereaming.com
Nowak Construction Co. Inc., (316) 794-8898, www.nowakconstruction.com
Mayer Specialty Services LLC, 316-794-1165, www.mayerllc.com