Published in September 2007 Australian Longwall Magazine

The 24-year-old longwall mine, near Lithgow in New South Wales, produced 3Mt during 2006, a rate that will be maintained and surpassed by the new longwall equipment.

The announcement comes after SK Corporation and Korea Resources Corporation (KORES) this year bought a 50% stake in the Centennial-owned mine for $A80 million providing the capital requirements to fund the upgrade.

Angus Place longwall superintendent Neil Moore told Australian Longwall Magazine the new outfit will consist of 160 Joy roof supports and a DBT armoured face conveyor (AFC).

Three of the mine's current gate end supports will be kept in use, bringing the total number of supports to 163 over a widened 283m face. Output from the new longwall will peak at 3.5Mtpa with an average of 3Mtpa, and a seam height of about 3.2m.

Moore said the supports have already begun arriving onsite from the UK and delivery will be completed by December this year. “We will set up about 30 supports for compatibility and training, and the remainder will be transported underground in the new year for a proposed start-up date of June 1, 2008," he said.

The new longwall supports are two-leg chocks, 1.75m wide with a total rating of 1070t and an operating height range from 1800mm to 3800mm.

DBT is supplying a complete set of PF6/1042 1.75m wide pans, re-routers and maingate gradient pans to match the 283m longwall, along with a set of ladder rack spilltrays, Jumbotrack 2000 shearer haulage and a set of 42mm x 146mm class S chain and flightbars.

The AFC pan lines will replace the existing 1.5m wide pans and connect directly to the existing main and tailgate drives.

The existing longwall equipment was originally installed in 1984 on a 200m wide face and has gradually grown in 25m extensions to the current 250m face. The Joy four-leg chock shields have worked in varying depths of cover from approximately 200m to the current 370m average.

Moore told AL the new supports will be a much-needed upgrade and will provide a “shot in the arm" approach to longwall automation. “The major challenge for keeping the old equipment going has been availability of spare parts, and the overall fatigue of the components," he said.

“Structures have minor cracks in the canopies and bases which require monitoring and repair and the electro hydraulic controls have been changed to have reliable adjacent control only, which makes operation slow and labour intensive.

“Most hydraulic cylinders have been replaced, all hydraulic hoses have been replaced and valving overhauled as needed."

The colliery has long been described as having the most challenging roof conditions of any coal mine in Australia and has put together a system it believes will safely and efficiently mine the remaining coal from the lease. Current support systems include minimising roadway width to 4.8m, fully meshing the roof and ribs, PUR injection, cable bolting, cribs, cans and roof and rib steel bolting and flexibolting.

Development rates are running at 30m per day and 750m per month using a Joy 12CM30 with four roof rigs and two rib bolting rigs, and Joy shuttle cars rebuilt as Waracars by Waratah Engineering.

With the new longwall in operation and an estimated 27Mt of reserves, Angus Place will continue producing for another 10 years, at which time the longwall equipment will most likely be moved to the neighbouring Springvale mine.

“There were no real unique specifications for the new equipment other than the basic design has to also be suitable to be used at our sister mine, Springvale," Moore said.

Centennial also plans to align other infrastructure, technical services and resources between Springvale and Angus Place to increase production efficiency and equipment utilisation.