The company has also been recognized recently for its forward thinking approach toward mine automation. In 2010, Eickhoff won an International Award at the BAUMA show in Germany as well as an RAG Research award for its automated SL 750 shearer. The machine is currently cutting its way through hard coal 1,500 m below the surface at the Auguste Victoria mine in Germany.

Not resting on its laurels, Eickhoff has produced the next highlight, the SL 900. “After reviewing the shearer product range, which consisted of four machine types, the SL 300 for lower seams, going upward to the SL 500, then to the SL 750 and finally to Eickhoff’s most powerful shearer, the SL 1000 with cutting height of 7 m, the company decided the product line was not complete,” said Marc Bartsch, sales engineer, Eickhoff.

As a result, the decision was made to supplement the product line with the SL 900. “Closing the gap between the SL 750 and the SL 1000, the SL 900 combines the compact dimensions of the SL 750 with the staggering power of the SL 1000,” Bartsch said. “Now, for the first time an Eickhoff shearer can cut coal from a wide spectrum of seams. It covers a huge range of cutting heights combined with more than enough power to deliver high production potential.”

The SL 900 shares the same qualities as the Eickhoff SL series:

  • Modular design simplifies transport and assembly;
  • No flange connections, instead a highly torsion-resistant tie rod system prevents casing cracks and delivers the high body stiffness;
  • A low machine profile offers maximum clearance resulting in increased coal transport volume underneath the machine and allowing operation in lower seams;
  • A high percentage of component interchangeability between different shearer types reduces a mine’s inventory;
  • Service-optimized positioning of components increases safety during maintenance and reduces downtime; and
  • Advanced automation and control features as well as diagnostic systems and machine monitoring that can be accessed anywhere.


“While keeping similar dimensions to the SL 750, the weight of the SL 900 is about 100 tons or 25 tons more than the SL 750,” Bartsch said. “This increase in weight required a considerably higher body stiffness. The higher cutting and haulage pull forces also called for a more robust design.”

All Eickhoff shearers are fully simulated and virtually tested using state-of-the art design tools. “Before the actual manufacturing process can begin, production is generally kicked off with the manufacture of high precision component castings at the company’s foundry,” Bartsch said.

“Size matters, but much more comes into play when you want to produce a successful machine,” Bartsch said. “As an example, the SL 900 can be equipped with SL 1000 and SL 750 cutting and haulage motors as well as ranging arms. If lower cutting heights are needed, the miners simply attach the SL 750 ranging arm and production can start.”

Most of the components in the SL 900 electrical distribution box are identical to those found in the SL 750 and SL 1000. “If a customer owns a variety of Eickhoff shearers, they will ultimately gain added value through lower stocking costs by maintaining smaller inventory levels,” Bartsch said.

The SL 900 has a height of 1,600 to 2,000 mm (5.25 to 6.5 ft) and a length of less than 15 m (49 ft) between drum centers. With a cutting height of 2,100-5,500 mm (6.5 to 18 ft), the shearer weighs 100 metric tons, with a haulage pull of more than 1,000 kiloNewtons with a total installed power of 2,354 kW.

Over the years, automation has played an ever-increasing role. The SL 900 builds on that platform with proven hardware solutions like inverters that control haulage speeds and industrial PCs with advanced visualization options. “Within the power units, which contain contactors and a number of protection components, the amount of wiring and peripheral devices inside the machine has been  reduced to an absolute minimum,” Bartsch said. “The amount of space that has been saved can now be used for a number of high tech solutions like infrared cameras for horizon control or radar technology for proximity detection.”

The inertial navigation systems allow operators to monitor its location with centimeter level accuracy. “With developments in software and hardware technology, processing times and data transmission rates have been improved and overall size of the machine units has been reduced,” Bartsch said.

Intelligent solutions enable the machines to make autonomous decisions from determining optimized cutting heights to sending vital machine parameters to operators at the face, to the surface or even all over the world. “All of this goes in line with maintaining the highest safety standards, improving the working environment and keeping an eye on the operator,” Bartsch said. “Although both active and passive systems control walkways and monitor cutting sequences, the operator always has the last word. He is always in control of the shearer.”

The SL 900 offers a visualization option beyond comparison, Bartsch explained. “The data obtained from the SL 900 can be redundantly transferred to a remote control station located in the headgate,” Bartsch said. “From the control station, the operator can take control of the shearer with high data transmission rates that allow for immediate reaction times. The operator can monitor parameters like oil pressures, haulage speeds, motor temperatures and the precise location of the shearer.”

Additionally cameras monitor the conveyor as well as the walkway streaming live information of what is going on in the face. “If necessary, one monitor can be used for the configuration of parameters for a state-based operation—another advanced feature available with the SL 900,” Bartsch said.

Since their introduction to the market, both the SL 750 and the SL 1000 have proven themselves under the harshest conditions, according to Eickhoff. The SL 750 provides customers with a sleek machine design and compact dimensions while the SL 1000 provides the highest machine power and immense cutting heights, Bartsch explained. “The decision to take the best of the two worlds and combine them in one machine was only possible through the implementation of state of the art design and production techniques,” Bartsch said. With this machine, Eickhoff has taken the next step in the evolution of high production longwall shearers.