All you need in the driller's seat

The Premium model of the Terra-Jet 8522 S is equipped with a comfortable driver’s cabin, which sets new standards. The cabin has all-round tinted glazing, with the machine side being glazed in a single uninterrupted panel. This allows the operator to see every detail of the drilling machine.

Large windscreen wipers with jets clean the front and right panels. Additionally the drilling fluid pressure inside the drill rods is automatically released just before each drill rod change, preventing bentonite from being splashed onto the glazing.

The on-board computer with a large 10.4 inch touch screen displays the vital information needed at any instance. It updates and saves all relevant machine data every two seconds, updating the operator on the essential drilling elements. This data is essential for efficient service diagnostics.

Article continues below…

Additionally a bore log can be printed for each bore as regulated in the German specification DVGW 321.

Sitting comfortably

The operator sits in a comfortable operator’s seat, which can be adjusted to suit the body shape and weight of the operator. The operator’s cab is wide, allowing the seat to rotate 180 degrees. The operator can drill looking in the drilling direction, or can rotate the seat to be at right angles to the drill and observe every detail of the drilling machine.

Machine technology

The Terra-Jet 8522 S may drill directional bores up to 400 m long and 1,000 mm in diameter depending on ground conditions.

Torque and pullback force are produced by separate hydraulic circuits allowing the maximum torque of 8,500 Nm and the maximum pullback force of 220 kN to be used simultaneously under full load.

Separate bentonite chamber

The drilling fluid volume is 400 litre per minute. The mixing system which mixes the bentonite into the drilling fluid via an injector (venture hopper) is on board the HDD machine. This patented system removes the need for an extra mixing system and a second engine.

The bentonite high pressure pump and the mixing pump are placed in a separate chamber between the driver’s cabin and engine chamber. This aesthetically pleasing solution ensures that no bentonite touches hydraulic components.

Automatic drilling

The machine is equipped with a second generation automatic drilling and backreaming system (ADBS). This patented system automatically adjusts the working speed of the drill to suite the ground conditions.

In soft ground the drill operates at maximum speed, in hard ground slowly. This allows the operator to operate the drill at maximum efficiency in a controlled and relaxed manner and prevents the drill rods and drilling tools from being overloaded. During the pilot bore the ADBS controls the thrust force. If the drill head hits an unexpected obstacle, the ADBS stops the drilling speed immediately and drills very slowly through the obstacle – all automatically!

Another new feature is the automatic drill rod greasing function, which is undertaken during each drill rod change by an electrically driven grease press attached to the driving saddle.

New operator’s concept

The drill operator drives and operates the HDD machine using the two multifunctional joysticks installed in the left and right armrests of the operator’s seat. Driving using the joysticks allows instantaneous control and smooth movement of the Terra-Jet.