Equipment: Vermeer® D16x20; StraightLine® 4″ RockEye® Air Hammer System; Ingersoll Rand 1100 cfm x 385 psi air compressor.
The Challenge: Five shots in five days, across existing water, gas and sewer lines, many located at corresponding depths, in city traffic. That was the challenge awarded to Utility Services Group in Greencastle, PA. Layered limestone with intermittent clay, in close proximity to existing lines, led Utility Service Group to contact StraightLine HDD for a solution. StraightLine deployed Ron Becker, lead field technician, with the RockEye™ Air Hammer system.
Each of the five bores was approximately 100′ in distance and in very tight easements. Due to the length of the shots being very short, the set up angle required the hammer to be steered 100%, through the length of each bore. With no margin for error, in varying soil conditions, precision steering around existing utilities was of utmost concern.
Outcome: The RockEye™ system’s steer-ability was tested through the layers of broken rock. Production was accomplished at approximately 25 minutes per rod. Control in the fractured rock certainly presented challenges, however, at the end of each bore the RockEye™ steered on target into the exit pit. Utility Services Group, Dustin Beck, concluded, “e;The RockEye™ performed very well, indeed. I really liked the lack of wear on the bit and housing. Overall, I found the system to be very efficient and user friendly.”