Extensive planning and the early and close cooperation of the mine with the three German companies allowed a problem-free implementation of the coal clearance system, a fast commissioning, and an error-free operation with a capacity of 500,000 tons per annum by April this year.

The ParkTeknik and ParkTermick mines are located near Cayirhan, 120 kilometres west of Ankara in Turkey. Operations are spread across four fields, with fields A, B, and F employing a double longwall face and field C working the top and bottom coal layers of the seam in a gigantic longwall face (4.6m).

From the time parent-company Park Holdings took over the operation of the mines it has continually worked to optimise the mines. Since fields A and F were taken over in 2000, changes in the mining operations and the coal clearance system, a complete reworking of the power supply, and the automation of the coal winning and mining processes have been realised.

In 2003, the face in Field C moved from the northern to the southern area. At the same time it was decided to implement the coal clearance system using clearance road A2201. Through this connection, the expensive costs of lorry transport of the highest volume coal output from Field C could be saved. The conclusion of work was planned for the commissioning of panel C02 at the beginning of December 2003.

Panel CO2 dips from south to north with changing inclinations. The conveyor route can be divided into two main sections, the first section with a length of 650 metres and a 12-gon slope (100 gon = 90 degrees), the second a length of 950 metres and a 9-gon slope.

To transport the coal output of 2000t/h the mine had to make extensive plans. When planning it was taken into account the dominant use of existing drive components and a long-term standardisation of the belt quality to 1250 N/mm at a belt width of 1200mm. The overall length of the belt conveyor road amounts to approximately five kilometres from the underground conveyor discharge to the power plant transfer point.

Due to the mining conditions, the coal clearance system was divided into six belts, of which two convey downwards. While one of the downwards-conveying belts (Cross-Cut A2302) was able to be planned in the classic manner with a rear drive and a controlled braking system, the downwards-conveying belts for bottom road C0210 of face C02 presented more of a challenging task. The changing slopes of Bottom Road C0210 and the necessary use of the existing underground conveyor discharge with integrated drive and belt turning bend proffered a real test.

The calculation of the drive output or brake horsepower of the coal clearance process in Road C0210 resulted in a required total drive output greater than 800kW. For mining-related reasons, a rear drive could not be used. In the case of a limitation of the standardised belt quality and the previous drive technology, three individual belt conveyors with a drive output of 220kW each would be necessary in the area having a 12-gon slope (650m road length) alone. A further belt conveyor with a drive output of 220kW would be required in a 950-metre partial area with a 9-gon slope.

The resulting disadvantages during the operation of the face due to the conversion of the belt conveyor justified the use of a supporting belt/driving belt conveyor. The extra expenses related to the acquisition of the drive technology and the additional conveyor belt were more than compensated by the optimisation of the coal clearance system and the low number of required braking systems.

The detailed planning of the supporting belt/driving belt drives was carried out by DBT Mining Engineers in co-operation with Maschinenfabrik Hese.

A two-layer belt was selected as the conveyor belt to create all belt connections using the hot vulcanisation method. The advantages of this method are lower costs, higher mechanical stability, and longer service life. A mechanical hook connection was planned only for shortening the belt.

A controlled braking system was required for the safe shutdown of the belt conveyor, and the mine selected the newly developed GBS III (DBP) braking system of Tüschen & Zimmermann.

On finalisation of the coal clearance configuration, the mine awarded DBT was awarded the contract for the delivery of the drive technology for both downwards-conveying belts. The control system technology was supplied by Becker Mining Systems.

The underground installation was able to be concluded within two weeks due to the optimum preparation of the installation sites, which meant the plants could be commissioned as planned.

With the system now up and running the recorded operating data and technical information continues to be exchanged regularly in close and good cooperation between the mine and its German partners.

Click here for full operating data.

This article was based on a paper by ParkTeknik and ParkTermik vice general manager Müdür Yakup Kayguzus, electrical systems and machine operation head Bernhard Baus, and Becker Mining System’s Andreas Scheid.