Posted on April 11, 2013 by Luke

Using DTD’s new Vermeer D36x50DR rig, we recently completed four road crossings near Fort Worth, Texas.  The “DR” is a versatile rig that has the ability to drill through both rock or dirt with surprising speed and accuracy.  It uses a dual-rod technology that mechanically rotates the drill bit with an inner rod (inside an outer rod), thereby negating the high volume of mud typically needed for a mud motor.  This allows us to drill through both hard rock and dirt while minimizing the risk of an inadvertent return of drilling fluid.

The 3650 was quickly put to the test with a 450? long bore under Sendera Road in Haslet, Texas.  This bore was designed to be drilled in line with a previously dug ditch line, cross under a road with several previously installed buried utilities, and exit at a 5? depth in line with another ditch line.  Making it even more difficult, the ground was a hard layered limestone. The DR rig drilled efficiently and accurately through the hard rock.

DTD then mobilized about 45 minutes north to Chico, Texas to drill three  more road crossings ranging in length from 140? to 180?.  These three bores were all drilled in a unconsolidated sand.  Even though each bore was short, they each required a high level of precision, having a specified 8? of depth under each road and 5? of depth in two previously excavated pits (PI pits) where the pipe line would be tied in.  On top of that we were required to be level in each pit to to ease the welding of each tie in.  Each crossing took about one day to complete, from start of drilling to pullback of the 6? steel pipe.

---