CONRAD Conrad Combi 500 HD

The Conrad Combi 500 HD is a crawler-mounted drilling rig designed for reverse circulation, airlift reverse circulation, percussive drilling, and direct-circulation rotary drilling.
The rig is mounted on a hydraulically driven crawler undercarriage measuring approximately 2.5 m in width, 4.6 m in length, and 0.85 m in height. The tracks are 600 mm wide and fitted with rubber pads. The frame features four independently operated hydraulic outriggers—two at the front and two at the rear—with a stroke of 1,000 mm. A hydraulic turntable allows the machine to rotate 360° in either direction without moving the tracks.
Power is provided by an Iveco FPT-C87-ENTZ Tier 4 / Stage IIII Final diesel engine delivering a maximum of 305 kW (415 hp) at 2,100 rpm. Maximum engine torque is 1,800 Nm at 1,500 rpm. The engine is housed in a sound-attenuated stainless steel enclosure with an integrated fuel tank; the tank capacity is optimized to a maximum of approximately 500 liters. The machine is equipped with an air compressor for pneumatic tools, rear-mounted air connections, and an additional low-mounted start switch.
The hydraulic system powers all drilling, travel, and auxiliary functions. An IQAN electrical control system monitors and operates the hydraulic functions; in the event of a malfunction, an emergency program allows the system to switch to manual control.
The drill mast is a welded box-section structure that is raised and lowered hydraulically. The mast features a travel range of up to 1.4 m and a maximum pullback force of approximately 40 tonnes when using the bottom clamp. For angle drilling, the mast can be adjusted from 90° to approximately 60° in 5° increments.
The pullback and pulldown system has an effective stroke of approximately 6 m. The maximum pullback force is 20,000 daN, and the maximum pulldown force is 9,000 daN. Normal pullback speed ranges from 0 to 0.3 m/s, high pullback speed from 0 to 0.65 m/s, and the maximum pulldown speed is 0.6 m/s. The machine includes a bit-weight control system.
The top drive has a diameter of 6 inches and a bore of 150 mm. In high-torque mode, it delivers 2,000 daNm at 10 to 50 rpm. In low-torque mode, it delivers 1,000 daNm at 10 to 100 rpm. Torque and rotational speed are adjustable from the control panel, where the speed is also displayed. A hydraulic breakout device located below the top drive provides up to 4,000 daNm of additional breakout torque. An air swivel is mounted below this device to supply air to the airlift drill pipes.
The hydraulic chuck and bottom clamp are designed for 5-inch double-walled airlift drill pipes. The bottom clamp can open laterally to provide unobstructed access to the borehole. The clearance beneath the clamp ranges from approximately 250 mm to 1,650 mm, depending on the mast adjustment. As a safety measure, the lower clamp and the chuck cannot be depressurized simultaneously during retraction, except following a deliberate manual override. Color indicators display the s