Photos: AME Drill Supply & Services
Down-the-hole (DTH) drilling is an essential element of some piling projects, which involves a DTH drilling hammer at the bottom of a drill string. It relies on three elements for drilling holes: bit loading (weight), rotation and air. When combined, it is highly efficient at crushing rock. As the drill string slowly rotates, the drilling hammer is repeatedly forced into the rock. Striking power is provided by compressed air driving a piston inside the hammer.
The fast hammer action breaks hard rock into small cuttings and dust that are evacuated by fluid (air, water or drilling mud). The DTH hammer is one of the fastest ways to drill hard rock.
Several advantages
DTH drilling offers several advantages over top-hammer drilling for larger and deeper holes in medium-hard formations. As the hammer is at the bottom of the hole, power loss is minimal as the hole deepens. This means that energy is not lost in the drill string and penetration rates do not markedly decline with depth, provided that back pressure does not rise significantly in the borehole. DTH drilling is most suitable for hole diameters of four to 10 inches, with some exceptions.
“Our drilling tools include DTH hammers in sizes from two inches to 24 inches, including valveless type; DTH bits, including valveless type and DTH drill pipes; casing drilling tools, including eccentric drilling system and symmetric drilling systems, and adaptors,” said Ame Drill general manager Daiwen Yang.
Decades of experience
Ame Drill began producing DTH drilling tools 30 years ago. From its small workshop, the company grew into a modernized factory with updated CNC machines and heat treatment systems.
“Our DTH hammer is a very important part of our DTH drilling tools,” said Yang. “Our research and development team is devoted to developing stable quality, high-penetration rate DTH hammers. High penetration rates mean consuming less air and less fuel, low drilling operation costs and high productivity.”
DTH drilling offers several advantages over top-hammer drilling for larger and deeper holes in medium-hard formations.
The DTH hammer is pneumatically powered with compressed air propelling it forward to impact and fracture rock. Compressed, it also travels through the drill bit into the hole (air exhaust), which blows the chips and dust out of the hole. As for how the company’s DTH hammer compares to other hammers on the market, Ame Drill’s prices are 60 per cent to 80 per cent lower.
“The penetration rate of our QL60 DTH hammers have achieved 20 per cent faster records in Pembroke, Ont., for hard granite for water well drilling compared to the same size of hammers of a competitor at the same location,” said Yang.
“And the penetration rate of our QL50 DTH hammers have achieved 35 per cent faster records in Quebec for sedimentary rock formation in a quarry compared to the same size of hammers of a competitor at the same location.”
With offices in both Moncton, and Burlington, Ont., Yang says that Ame Drill remains committed to working with its dealers in different locations in an ongoing effort to provide service to its end users.
“Our target is two or three warehouses and different dealers in the western part of Canada in the future,” he said. “At that time, companies all over the country will be able to get our tools quickly – either the same day or no more than two days. They can also receive localized specialized services from our dealers very easily.” 