Dual Rotary Drilling Rig


The DR-24HD (‘heavy-duty’) features a heavy-duty gear-driven lower drive, which generates two and a half times the torque of the standard DR-24. The DR-24HD is also configured with a heavy-duty mast to withstand the additional torque and larger hoist cylinders for increased pullback capabilities. The DR-24HD is most commonly used in deep, large diameter applications such as municipal/industrial wells and mine de-watering.


Foremost Dual Rotary drills feature a unique lower rotary drive that is used to advance steel casing through unconsolidated overburden, such as sand, gravel, glacial till, and boulders. Pullback, pulldown, and rotational forces are effectively transmitted to the casing via high-strength steel jaws with carbide inserts.

An independent rotary top drive simultaneously handles a drill string equipped with a down-the-hole hammer, drag bit, or roller cone bit. Cuttings are typically evacuated with air, but Foremost DR Drills can also be configured with pumps for mud or flooded reverse circulation drilling.

The top and lower drives feed independently, meaning that the bit position can vary relative to the bottom of the casing. Once the desired casing depth has been achieved, the DR continues drilling open-hole like a conventional top drive drill. With a Foremost DR Drill, there is no need to trip out or change tools when transitioning to open-hole drilling.

Top 10 Reasons to Consider a Foremost Dual Rotary Drill

  1. Exceptional Overburden Performance – Foremost DR Drills have been proven repeatedly in some of the toughest unconsolidated overburden formations, including sand, gravel, glacial till, and boulders.
  2. Open-Hole Versatility – The DR can be configured for a variety of drilling methods including mud, reverse circulation, and flooded reverse circulation.
  3. Straight Holes – The rotation of the casing by the lower drive results in a very straight hole making it ideal for shaft holes and foundation piles. This also minimizes stress on casing and casing welds, and eases the task of installing screens and pumps in water well applications.
  4. Basin Extraction – The lower drive is equally effective at pulling back casing; thereby simplifying the process of exposing a well screen or abandoning a well.
  5. Utilizes Conventional Tools – The drill string can be equipped with down-the-hole hammer, roller cone, or drag bit.
  6. Control of Discharge – Cuttings are diverted through the discharge swivel and can be directed to a safe and convenient dumping or monitoring point.
  7. Ease of Maintenance – Foremost DR rigs feature a directly connected hydraulic feed system which means no chains, sheaves, or sprockets to maintain. This type of feed system generates zero load on the mast crown, permitting a simple and lightweight mast design that does not sacrifice pullback capability.
  8. Reduced Operational Risk – The DR’s flexibility allows you to expand into new applications and gives you confidence to go into areas previously considered off-limits. You will know you have the right equipment to get the hole down the first time!
  9. Resale Value – There is arguably no drill on the market today that holds its value better than a Foremost DR. Dual Rotary owners tend to hold onto their rigs, making used inventory scarce, making for easy re-sale should the need arise.
  10. Foremost Technical Support – Foremost’s DR rigs are backed by the expertise and support of our product management team, field technicians, and one of the largest engineering departments in the industry.

Since acquiring the Dual Rotary technology from Barber Industries in 1993, Foremost has continually updated, refined and expanded the DR line with the goal of enhancing its functionality and extending its range of applications. Today, Foremost offers several DR models, each packed with features that deliver heightened safety, productivity, and profitability across a variety of drilling activities.

DR-24HD DR-24HD cyclone


The optional cyclone sample collecting system slows discharge velocity to allow accurate and continuous sampling of the formation.

DR-24HD DR-24HD discharge swivel


All drill cuttings rise to the surface between the drill pipe and casing, and exit through the discharge swivel attached to the top of the casing. The discharge swivel directs cuttings to a safe dumping point or to an optional cyclone collection system.

DR-24HD DR-24HD casing shoe


A carbide-studded casing shoe is welded to the casing bottom. The shoe I.D. is flush with the casing I.D. so that there is no reduction in the bore hole diameter when switching to open-hole drilling.

DR-24HD DR-24HD casing jaws


Rotation and feed forces are effectively transmitted from the lower drive to the casing via a set of three carbide inserts. Casing jaws are available for all common casing sizes and can be changed out quickly in the field.

DR-24HD DR-24HD tilting top drive


The independent hydraulic top drive tilts for convenient loading of drill pipe and casing with the operator standing at ground level.

DR-24HD DR-24HD lower drive


The lower rotary drive is also used as a powerful breakout and spinner for drill pipe, hammers, bits, and thread casing.

Top Drive
Stroke 26 ft 7.92 m
Hoist Speed – Up 78 ft/min 24 m/min
Hoist Capacity – Pullback 84,000 lbs 38,100 kg
Hoist Capacity – Pulldown 25,900 lbs 11,800 kg
Torque (stall) 14,500 ft-lbs 19,600 Nm
Rotation Speed 0 – 86 rpm
Lower Drive
Stroke 12 ft 3.66 m
Hoist Capacity – Pullback 75,400 lbs 34,200 kg
Hoist Capacity – Pulldown 33,000 lbs 15,000 kg
Torque 1,000,000 in-lbs 112,000 Nm
Rotation Speed 0 – 21 rpm
Max. Casing Diameter 24” 609.6 mm
Air Flow 900 -1150 cfm 25.5 m3/min
Pressure 350 psi 24.1 bar
Engine Power 525 hp 391 kW
Length 38 ft 9 in 11.81 m
Height 13 ft 6 in 4.11 m
Width 8 ft 2.44 m
Weight 56,000 – 72,000 lbs 25,400 – 32,650 kg
Jib Boom Winch
Wire Rope Length 140 ft 42.67 m
Wire Rope Diameter ½” 12.70 mm
Line Pull on Bare Drum 6,000 lbs 2720 kg
Line Speed on Full Drum 100 ft/min 30 m/min
Water & Foam Injection
Capacity 20 gpm 75 l/min
Pressure 600 psi 41.4 bar
Hydraulic Breakout Lower rotary casing drive is used as a breakout and spinner wrench for drill pipe joints, drill bits, and threaded casing.
Hydraulic System A closed loop hydraulic system is used for the lower casing rotator. Variable displacement pumps are used for all other hydraulic systems.
Hoist System The hoist feed is direct by hydraulic cylinder; no cables, sheaves, chains, or sprockets are used in the hoist system.
Carrier Truck, trailer, crane carrier, or self-propelled track carrier.
OPTIONS: · RC drilling package
· Sandline winch
· Mud pumps
· Hydraulic welder
· Cyclone separator

Performance specifications are theoretical maximums. Actual performance may vary.

DRILLING PENETRATION RATES (Based on Independent Third-Party Observations)*

Foremost DR Conventional Air Rotary Auger Cable Tool
Drilling Speed1
   Sand & Gravel 20 – 40 min 45 – 90 min 30 – 60 min 1 – 4 hrs
   Till 30 – 60 min 45 – 90 min 30 – 120 min 2 – 8 hrs
   Rock 30 – 90 min 30 – 90 min n/a n/a
Casing Integrity Excellent Moderate – poor n/a Moderate
Split Spoon Sampling Ability Moderate – Poor Poor – None3 Excellent Good
Cross-Contamination Good – Excellent Moderate – Poor Moderate – Poor Moderate – Poor
Versatility Excellent Good3 Moderate – Excellent Poor
   Air Yes Yes 3 No
   Mud Yes Yes 3 3
   Water Yes Yes 3 Yes
Other Advantages/Disadvantages – Casing removal simplified – Controlled discharge sampling – Good casing seat in bedrock Poor casing seat by juttering and drive shoe removal Mobile rig for tough access Rig simplicity

1 Drilling speed shown represents average time required to drill and install 20 feet over a 100 foot well depth. 2 N/A denotes “Not Applicable” 3 Rig type dependent *Reprinted with the permission of the National Ground Water Association © 1988


Foremost Dual Rotary Drills Overview (English)

Foremost Dual Rotary Drills Overview (Spanish)

Foremost Dual Rotary Drills Overview (French)



North America Inquiries

E-mail: rick.finney@foremost.ca
Phone (Toll Free Canada/USA): 1-800-661-9190, ext 5812
Phone (worldwide): 1-403-295-5800


International Inquiries

E-mail: doug.secord@foremost.ca
Phone (Toll Free Canada/USA): 1-800-661-9190, ext 5819
Phone (worldwide): 1-403-295-5800