Off highway machines
Hendrik Stroet
Product Manager, Oil-air and oil-water cooler, KTR Germany
May 2026 • Trenchless drilling offers many advantages including less earth moving, less noise, less effort and lower outlays. For example, when a drill pipe penetrates the ground it can tunnel beneath a road or a body of water and – just like a mole – emerge into daylight on the other side. This saves costs and avoids traffic disruption.
The German TRACTO company based in the Sauerland manufactures drilling machinery which is perfectly suited for this type of work. Their Grundodrill HDD JSC and ACS models launched in 2019 comprise the latest and most powerful generation of steerable drilling systems.
Their ‘Nodig’ (short for ‘no digging’) technology is utilised for trenchless pipe-laying and offers a sustainable alternative to conventional civil engineering methods.
A module-based design combined with maximum automation allows the machine employed to be configured exactly according to a user’s requirements. This applies to various performance classes and drill rods for conventional soils or hard rock. The operator controls all key functions by means of a central touchscreen which also doubles as a remote control.
Sensor-assisted drilling – remote-controlled and user friendly
With the HDD (Horizontal Directional Drilling) method, a monitoring receiver tracks the position of the drill head, enabling three-dimensional control of the pilot borehole. This allows, for example, obstacles to be bypassed or drilled under. When the drill head is withdrawn, the borehole is enlarged and the attached pipe is pulled into the drilled route.
Depending on the model used, a Grundodrill JCS or ACS operator can lay pipes in different substrates with diameters of up to 1,100 millimetres and distances of up to 700 metres without trenching – all from the comfort of the driver’s cabin or by remote control.
As different substrates require differing drilling methods, two HDD systems can be employed: the ‘Jet Condition System (JCS)’ featuring single-tube rods for drilling in regular soils and loose rock or the ‘All Condition System (ACS)’ with double-tube rods for complex geological conditions and rock. In both cases the drill rods are screwed together fully automatically, then unscrewed during retraction and kept in the drilling rig storage compartment.
Made in Sauerland – using best-quality components
In addition to the modular design and the Made in Sauerland policy, TRACTO’s production philosophy focuses on the use of high-quality components. That is why the company’s developers in the town of Lennestadt work closely with KTR when it comes to couplings in the drivetrain, as well as the cooling of the heavy-duty construction machinery drives.
The new generation, GRUNDODRILL ACS300 – Premier League
When you see the size of the cooler installed in the ACS300, you can get an idea of the cooling capacity we need to provide for the hydraulic system.
Thomas Himmelreich
Construction DRILL/PIT
Custom-made cooling
The primary drive for Grundodrill HDD flush drilling rigs is powered by Cummins diesel motors with power ranging from 100 to 231 kilowatts, certified to meet Stage V emissions standards. They drive the hydraulic crawler undercarriage, the boring mill and the high-performance bentonite HD pumps for the flushing fluid as well as the handling unit for the drill rod.
As both the engine and hydraulic system operate at high continuous output, especially during drilling operations, the cooling system has to be suitably designed, taking into account that the new machinery is engineered to fit into very limited spaces. Given these conditions, the MMC combined cooler was the logical choice. This multiple-circuit cooler safeguards the temperature for engine coolant, hydraulic oil and charge air. The Grundodrill machines are equipped with a range of MMC models, all of which have been specially designed for this application. Some versions feature two compact MMC cooling systems.
GRUNDODRILL HDD drilling rig 18ACS – King of Rock
Robust and long-lasting couplings
KTR curved-tooth flange couplings are deployed at the connection between the motor and the hydraulic pump to ensure reliable, positive-locking torque transmission while simultaneously compensating for shaft misalignment. The couplings are mounted directly on the flywheel and contribute significantly towards protecting the adjacent components. Depending on the motor capacity and installation conditions, BoWex FLE-PA couplings with a connecting flange made of glass-fibre-reinforced polyamide are used, or alternatively FLE-PAC couplings with a connecting flange made of a carbon-fibre composite.
GRUNDODRILL 28Nplus Fluid-Assisted HDD rig – Top Performer
The bottom line: always a good connection
Thanks to KTR couplings and combined coolers which are Made in Münsterland, TRACTO’s Nodig machines deliver consistently high performance and the Grundodrill range provides the construction industry across the world with solutions that simply makes building more efficient – without the need for trenching.
Last but not least
All GRUNDODRILL hdd drilling rigs are fitted with a high-pressure cleaner as standard. A ROTEX coupling connects the hydraulic motor to the pump.





