With an MOBIREX MR 122 Z impact crusher from Kleemann, the Scottish quarry operator, Grange Quarry Limited, recently strengthened their fleet of machines. Founded in 2000, Grange Quarry Ltd is now one of the largest manufacturers of high-quality aggregates and ready-mixed concrete in the south of Scotland and the north of England.
For Grange Quarry, the MOBIREX MR 122 Z impact crusher is not the first plant that they have acquired from Kleemann. “Since 2012, we have been working successfully with a mobile MOBICAT MC 110 Z jaw crusher”, explains Stuart Dodd, owner and Managing Director. They use this mobile plant to crush whinstone at Grange Quarry, Lockerbie for road construction with a maximum feed size of 600 mm to 125 mm at an output of around 200 t of crushed material per hour. Since 2012, Grange Quarry Ltd has also been developing Kelhead Quarry near Annan. At this site, Managing Director Mr Dodd also uses a plant from the same German manufacturer to process the stone.
The new MR 122 Z impact crusher has been in use since October 2013 and crushes limestone breccia of 600 mm that is produced by the blasting to a final grain of 60 mm (Fig.). With an output of around 220 t/h, Grange Quarry is extremely satisfied with the product. The crushed stone is mainly used as concrete aggregate and to produce a high quality crushed rock sand.
The crusher with its 250 kW electric drive, which is supplied by a 364 kW diesel engine, crushes heavily reinforced concrete just as easily as limestone blocks. This means that the classic MR 122 Z crushing plant is also ideal for concrete recycling. Another advantage is that the standard vibrating discharge chute under the crusher reduces wear on the crusher discharge conveyor and thus significantly increases the operational safety of the plant. This high level of reliability was one of the decisive factors in Stuart Dodd again investing in a plant from Kleemann. But he is also impressed by the crusher technology and the quality of the granulation: “The crushed stone has an outstanding cubicity,” in the opinion of the Managing Director.
In addition, the entirely electrical drives ensure the extremely economical operation of the plant. Experiences in the Kelhead Quarry underline this: “The MR 122 Z consumes around 35 l of diesel per hour compared to our previous impact crusher of the same size using 60 l per hour.”
Last but not least, the maintenance of the plant was also an important point to consider for the quarry operator. This is where the Kleemann plant scores Brownie points. On the one hand, their plants have easily accessible maintenance points and, on the other hand, fast and professional service is provided by the Wirtgen Group. Grange Quarry Ltd’s maintenance needs are taken care of by the Wirtgen Limited subsidiary, which has its headquarters in Lincoln, and which is responsible for sales and after-sales service for Kleemann crushers in Great Britain.