Profitable productionMarch 8th, 2012 | Posted by in T3W
It can’t be stressed enough that, although geothermal drilling is done with all the same equipment and tooling as water well drilling, geothermal drilling requires a different mindset. Drillers who have done quarry work know what it means to punch holes in the ground to meet the footage demands of the customer.
Geothermal work follows the same production drilling philosophy. Jackson & Sons Drilling has gone so far to emphasize the difference in their business that they have changed their marketing name to reflect the nature of their work: Jackson Geothermal.
The company currently operates 15 drills, with the bulk of their work on geothermal projects. For the first six months of the year, the company logged 508,000 drilled feet (154,838 meters).
The crew works within an eight-hour drive of their Ohio-based company, focusing on large- but will take the small- geothermal projects. Geothermal Manager Mark Southward said, “Seventy to 80 percent of our jobs are commercial geothermal projects.”
It was on a recent 92,110 foot (28,075 meters) project at the Green County Career Center in Xenia, Ohio, that the company raised the bar on productivity by setting a footage record using an Atlas Copco T3W. In one day, driller Nick Sprowls and his helper, Josh Crawford, drilled 3,050 feet (930 meters).
The 17-man crew operated seven rigs on the job to complete the project in 10 days, averaging 1,309 feet (399 meters) per rig each day. But the performance of individual drills on certain days helped them overall. For example, on two different days, two 20-year-old Atlas Copco TH55s each completed 2,440 feet (744 meters) of drilling in a shift.
The company doesn’t consider a hole completed until it is drilled and the loop is grouted in place. On this project, each well required setting the loop, then pulling the 20 foot (6.1 meters) surface casing for each 305 foot (93 meters) hole. Bedrock began at approximately 18 feet (5.5 meters).
The day Sprowls completed 3,050 feet (930 meters), his day began just after 7 a.m., logging his first rod at 7:30 a.m. and signing off on his last hole at 7:45 p.m. Sprowls averaged 2,064 feet (629 meters) a day for 10,320 feet (3,156 meters) in each five-day week. This is not uncommon for him. Year to date, Sprowls has logged 75,000 drilled feet (22,860 meters) on five different rigs with 25,455 feet (7,759 meters) from June alone.
Southward emphasizes that all his men work as a team with no one standing alone. Owner Jim Jackson has gone to the extent of printing the name “Team Jackson” on uniforms worn by the men to highlight the team effort needed for everyone to keep these numbers up.
Dave Tingley was the site foreman on the Green County project and was a major reason for its overall success. Southward said, “Dave breaks in all the new rigs and keeps things moving smoothly. He may have been the driller setting the record that day if he hadn’t been supporting the crew on another task.”
Southward said, “We have other drills that can drill just as fast in the first 100 feet (30.48 meters), but nothing can keep up with the new T3W in a full day. The T3W really gets down and out of a hole; it’s definitely a production-based rig.”
Southward points out that all his drills use the Atlas Copco Secoroc TD40 down-the-hole hammer with the Rocket Bit. “We did 302 holes in 10 days, and that hammer is what got us there.” He said the Rocket Bit works so well in a limestone formation because of its aggressive button structure and air channels. “It is the perfect bit for us because it cleans away from the face so well,” he said.
Jackson used another manufacturer’s hammer in the past, but found rebuilding the Atlas Copco hammers was a better value. “Our other hammers were cheaper, throwaway hammers. Now we work with our distributor, Stockdale Mine Supply, to service the hammers.” Each rig has multiple hammers on site and changes out when necessary. “We don’t mess around with a slow hammer. If it’s slowing down, we change it out and call Randy.”
Randy Neff is Jackson’s Stockdale contact. He said he put Jackson on a hammer contract for rebuilding hammers. Neff said, “An efficient hammer drills a hole faster, Jackson doesn’t waste time with hammers and we know what to look for when pulling it apart.”
Jackson also drills 5-inch (12.7 centimeters) holes when the rock formation requires it, but not in limestone. For 5-inch (12.7 centimeters) work they use the Atlas Copco Secoroc TD50 hammer.
Cutting back on air also allows them to be more fuel efficient. “With the 4-inch (10.2 centimeters) hammer you only need 560 cfm. The 5-inch (12.7 centimeters) requires 900 cfm. This is production drilling and it’s all about knowing and managing physical costs,” said Southward.
For example, the company’s two TH55 drill rigs do not have on-board air, so the crew drills using airpower from an 1,170 cfm 350 psi auxiliary compressor supplying air to both rigs. Sharing air from one compressor allows them to use less fuel. Each rig drags a hose, drilling five holes before the compressor needs to be pulled forward with a dozer. The newer T3W with Atlas Copco’s Electronic Air Regulation System (EARS) allows the air compressor’s volume and pressure to be dialed back, saving on fuel to supply the necessary air.
Years of experience has given the Jackson crew members a chance to understand where they need to make adjustments and outfit a fleet while being cost conscious. Southward reiterated, “We know what each rig will do. First, it’s about knowing your physical costs. Then it’s all about production.”