Develon has launched the DX235RTF-7 Tunnelling Excavator, a new extension to the company’s line-up of Special Application machines. The DX235RTF-7 is based on Develon’s well-established DX235LCR-7 reduced radius crawler excavator and is powered by a DL06V Stage V engine, providing 141 kW (189 HP) of power.

The DX235RTF-7 utilises the successful compact design and minimum swing radius of the DX235LCR-7, but the key part of the machine is the heavy duty Tunnelling Front, offering a new arm and boom design with special kinematics and a tilting function.

Jan Breburda, Special Applications Product Manager for Develon Europe, commented:  “The new DX235RTF-7 tunnelling machine is designed for superior performance in challenging underground environments. Complementing the safety and comfort of its operation, the advanced hydraulics and robust construction of the DX235RTF-7 ensure optimal power and durability, while its compact design allows for easy navigation in tight spaces.”

The Specifications

The DX235RTF-7 has a total operating weight of 25,689 kg and offers a maximum reach of 9260 mm. The kinematics of the tunnelling front on the DX235RTF-7 excavator are designed to prioritize horizontal reach and precision over vertical movement. The special kinematics are based around a boom tilting function, providing a 45°/45° tilt in two directions, the movement of which can be operated via a pedal in the operator’s cab.

The boom and arm configuration is specifically designed for operation in narrow areas, with ranges of movement slightly limited compared to the standard front on the DX235LCR-7. The DX235RTF-7 is specifically suited to work in restricted environments, without using the swing movement in narrow areas. This allows the DX235RTF-7 to work efficiently in narrow tunnels with the ability to reach the tunnel face and walls, while maintaining a low profile to navigate tight spaces.

Operator Safety

For work in confined spaces, the DX235RTF-7 features protective equipment to safeguard against falling debris or contact of the arm with the tunnel ceiling and walls. As a result, the DX235RTF-7 has a level 2 FOG system combined with more heavy duty covers and hydraulic piping protection.

The protection also includes covers over hydraulic hoses and arm work lights, as well as enclosing the bucket cylinder and links in a dedicated protective compartment and hiding the arm cylinder under the arm.

Compared to the standard DX235LCR-7 model, the DX235RTF-7 has six LED work lights, four on the front and two on the back, as well as AVM cameras as standard. Other features include PERO rotating piping, centralized greasing points and a dozer blade as an option. The specifications also include a 6.4 tonne counterweight and 600 mm wide triple grouser track shoes.

Tunnelling applications often require the transportation of the machine to areas with limited access, so the DX235RTF-7 is designed to be simple to lift and manoeuvre into place.