Working in a room and pillar operation, the Joy system started operations during May last year at the Chirimiri Anjun Hill Mine, South Eastern Coalfields.
The complete Joy system consists of a 12CM15 continuous miner, two 10SC32 shuttle cars, a Stamler feeder breaker, a JOY Quadbolter (mobile roofbolting machine) and an electrical distribution system.
Since start up, the system has averaged over 40,000 tonnes (44,092 tons) per month on the development of a five entry room and pillar system and has now achieved over 50,000 tonnes (55,116 tons) in a month on pillar removal (de-pillaring).
To date, the de-pillaring operations have been very successful providing the only approved method of mechanised de-pillaring in India.
As well as providing the equipment, Joy has also supplied a service team of 15 men to cover supervision, maintenance and operations over two ten hour shifts per day.
The team has achieved an average production of 1342 tonnes (1479 tons) per day and a total output for the year of 450,705 tonnes (496,817 tons).
Total bolts for the first year numbered 49,201 with an average of 150 roof bolts per day. Average advancement per day was 42 metres (137 feet).
The production in the first year has made a significant contribution of over 20% to the Chirimiri group output of approximately 2 million tonnes (2.2 million tons).
In the period June to mid-August the mine has already reached 152,000 tonnes (168,000 tons) which, if continuing on the current rate, should exceed last year’s records.
Joy said the scope for the application of this technology into other mines in India was vast.
“Currently millions of tonnes are tied up in pillars with no other means of extraction. Millions of tonnes exist in thick flat seams ideal for continuous miner mechanized room and pillar extraction,” said Joy Mining Machinery.
The Chirimiri Anjun Hill mine is a hillside deposit. Access is by adit with a rising drift at 1:5 up a vertical distance of 80 metres (266 feet) to the ‘zero’ seam which is 4.5 m (14.7 feet) thick with a reserve of 1.1 million tonnes (1.2 million tons).
The immediate roof is interbedded coal and mudstones between 1.5m (4.9 feet) and 2.5m (8.2 feet) thick overlain by fine coarse grained sandstone and the floor is sandy shale.