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Dual Rotary Drill Rigs (2)

Dual rotary drill rigs, as the name implies, are drill rigs that have two rotary drive mechanisms, an upper rotary head and a high torque lower drive unit. The DR-24 rigs provide exceptional overburden drilling in unconsolidated formations consisting of sands, gravels, glacial tills and boulders. Other conventional drilling methods can have serious problems drilling these formations, especially glacial tills and boulders.


The DR-24 HD generates two and a half times the torque of the standard DR-24. Its heavy-duty mast is built to withstand the additional torque and larger hoist cylinders for increased pullback capabilities. The DR-24 HD is right at home drilling deep, large diameter applications including municipal wells, industrial wells, environmental wells, exploration boreholes, injection wells, aquifer storage and recovery ASR wells, mine dewatering wells, elevator shaft drilling, construction drilling, and various other types of drilling applications.

Dual Rotary Drill Rigs – How They Work

1 - DR-24 HD truck mounted rig
1 - DR-24 SD truck mounted rig

Drilling technical details. In addition to the heavy-duty gear-driven lower drive there is an independent rotary top drive that operates simultaneously to handle a drill string equipped with a down-the-hole hammer, drag bit or roller cone bit. The top and lower drives feed independently allowing the bit position to vary relative to the bottom of the casing - this capability provides the ability to case off upper unstable formations and continue with open hole drilling techniques. Telescoping casings can be implemented to case off upper zones of contamination or to stabilize previously drilled formations. This also increases depth capabilities by reducing sidewall friction on the casing and drill strings.

Click to visit the Foremost site for more details on the DR-24 drill rig.

Contact us today to talk with a drilling professional about putting the power of a dual rotary drill rig to work on your next project.

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