Clowser Well Service, a regional expert in gas exploration drilling, was recently called upon to help increase production on active gas reserves that had been in existence for the past 10 years. This was accomplished by deepening the hole almost 2000 feet (610 m) that proved to be the perfect situation for using Numa’s new PCD carbide bit. Clowser was selected for this project because of their reputation for providing superior results in the gas drilling industry.
The existing hole was originally drilled to a depth of 3715 feet (1133 m) but was no longer yielding the proper flow of gas. In order to reach a deeper pay zone, Clowser selected a Numa Champion 40 down hole hammer and 4-3/4 inch (121 mm) PCD bit. The new bit was chosen because it was specially designed for oil and gas drilling applications consisting of highly abrasive and medium hard rock formations. Due to its special characteristics, the diamond carbide has many benefits over standard carbide. The PCD carbide is 3 to 5 times harder, 100% more wear resistant and has a compressive strength that is 115% stronger than standard carbide. All of this provides a longer lasting bit that is able to continue drilling where as bits using standard carbide would need to be replaced or repaired several times during this one hole. Due to the increased strength and wear resistance of Numa’s PCD carbide, the bits will not lose gauge size. This allows the operator to run DTH products longer and deeper.
Clowser set-up over the hole with a Cooper 150 rig having 1050/150 CFM/PSI (496 L/Sec / 10.2 Bar) of air and a 600 psi (40.8 bar) booster. Project requirements deemed Clowser to trip down 5-1/2″ (140 mm) casing to the bottom of the hole to begin drilling a 4-3/4″ (121 mm) hole through a shale and sandstone formation. When they began drilling, Clowser quickly realized that the hole would not dry up so they began using foam and water injection to properly clean the hole. This decision was critical to providing the proper conditions to maximize the drilling efficiencies of the PCD carbide bit. Drilling continued until a final depth of 5655 feet (1725 m) was reached which took only 42 hours to complete. The penetration rate for the Champion 40 and PCD bit averaged out to be a 46.2 feet (14 m) per hours.
Typically in the past, methods used for drilling gas holes deeper included the use of roller cone bits and/or journal bearing bits. Neither of these provided a cost effective way of drilling in this type of application due to their limited life cycle and very high cost. If roller cone bits were used on this hole, it would have required two possibly three bits to be used instead of the one PCD carbide bit it took Clowser. In fact, the one Numa PCD bit used showed no measurable wear after drilling the hole and could be used on future projects. In addition to requiring multiple bits to be used, roller bits drill at a much slower rate than the PCD style bits. The longer amount of time required to drill would have increased fuel cost and rig time to trip in and out of the hole to replace bits. On this project alone, Numa’s drilling products reduced Clowser’s cost by 50% with even further savings on the horizon.
When Clowser Well Services was charged with the task of finding the most cost-effective means of drilling deeper in the gas patch, they partnered with Numa to achieve their desired results. With Clowser’s expertise and Numa’s performance driven Champion 40 hammer and PCD carbide bit, this project was a complete success from top to bottom of the hole.