Hardly any other equipment is exposed to such high loads in daily use as a tunnel boring machine. This applies to its drive technology in general, and to the drill heads in particular.
Failure caused by defects costs not only time, but above all money. This is one reason why we leave nothing to chance in the development and production of our components, trusting the expertise, knowledge and experience of our engineers and technicians. This enables us to manufacture drill heads for every type of rock or soil structure. In addition, we produce and provide the accessories and spare parts required for our drill heads – perfectly matched components that meet the highest requirements. It is not without reason that our roller cutters in particular are characterised by exceptional resistance and durability. It is not for nothing that our cutting rollers in particular are characterised by exceptional resistance and durability.

Tunneling using underground or cut-and-cover methods

Tunnelling places the highest demands on people and technology. Tunnelling is about opening up underground spaces so that new paths can be created there. The tunnel boring machines (TBMs) have to deliver unimaginable performance in order to drive successfully. In addition to the machine, the drill head in particular must be stable and adapted to the rock layer.

As different as the rock strata are in the regions of this earth, as individual are the resulting demands on the material used on the one hand and the method required in each case on the other. Basically, there are two construction methods:

  • One is known above all to the people in our region, underground mining. For many decades, this part of Germany has been known worldwide for its mining industry and the technical achievements that were made there. This knowledge, the services rendered and the takeover of the drilling technology division of the mining and tunnelling specialist Kolk GmbH enable Mika Drilling to manufacture high-quality excavation tools in tunnel construction.
  • In general, tunnels can also be constructed using the cut-and-cover method. However, the closed construction method is often used. The tunnelling is then carried out either in the mining method or in the mechanical full cut method by TVMs.

New paths, new possibilities - tunnel construction for logistics

The machines that drive the drill heads we manufacture enable long tunnels, often used for roads or railway tracks. Our drill heads cut through almost any rock in the tunnel safely and without much wear. The tunnelling machines can thus do their work and ensure that new routes are opened up. For example, we have been ensuring for many years that industrial rail and road networks can be expanded or restored quickly.

The rock becomes harder or a cavity appears? No problem for our tunnel!

Here, too, there are two methods used in tunneling. One possibility is that ISP (Integrated Seismic Prediction) is used. In simple terms, a hammer blow is applied to the wall and the type of wave can be used to measure what type of rock lies in front of the tunnel boring machine. The second option consists of a second, smaller TBM drilling ahead. In some cases, these TBMs can collect information about the rock up to 100 m before the actual drilling, so there are no surprises waiting for you.

Mechanical drilling should be carried out following an extensive soil and rock analysis. Professional planning is supported by the quality of our drill heads.

The relevant experience of our team of engineers and technicians in tunnel construction and operations in all continents gives you the security of knowing that you are working with men who are best equipped for the job.

Rock cutting technology has developed into a highly technical branch of industry. The requirements in the areas of tunnelling and well construction as well as in special civil engineering and mining demand the highest level of technology and engineering services. For these tasks, they have an absolutely competent and reliable partner in Mika Drilling.


Tunnel construction ensures that underground cavities are created. Mostly, the tunnels are built for the infrastructure of traffic arteries or supply lines of any kind.

  • Cutting rollers and drill heads designed and manufactured by MIKA Drilling are the result of decades of experience in the field of drilling technology in mining, tunnelling and special civil engineering.
  • The bearings of the cutting rollers are designed as full complement cylindrical roller bearings in the radial area and as cage bearings in the axial area.
  • All bearing parts are designed as surface-hardened parts. This results in a hard, wear-resistant bearing raceway with a tough, impact-resistant core. The geometry and accuracy with the associated narrow tolerances of the bearing raceways provide high load capacity reserves.
  • The seals of the bearings are made of a special wear-resistant chilled cast iron.
  • A lubricant adapted to the needs of drilling technology ensures low wear and thus a long bearing life as well as good emergency running properties.
  • The cutting rims are made of highly tempered steel with hardened surfaces. Carbide pins are pressed into these cutting rims. The bores of the carbide pins are produced on a machine specially designed for this purpose. The tolerances and surfaces used ensure a reliable fit and optimum power transmission to the rock to be drilled.
  • The carbide pins are made of a further developed carbide mixture with a high WC content and a particularly fine, uniform structure. This results in high wear resistance and high flexural strength.
  • For the production of the individual parts, we use high-quality materials with the best properties.
  • All materials have a material test certificate according to EN10204 – 3.1b.
  • The carbide comes from German production and is specially matched to the areas of application with our supplier.
  • The design and manufacture is carried out in-house.
  • Due to the flexibility of the design and manufacturing, we are able to adapt the cutting rollers to the respective machine and drill head, for example by using different axle ends. Due to the modular design of the cutting roller bearing and cutting edge (ring tooth or cutting ring), it is possible to adapt the equipment of a drill head to the existing geology.
  • We design and manufacture special solutions for special requirements and operating conditions.