McLanahan readies second DDC-Sizer for Queensland coal mine

McLanahan says it has won a second DDC-Sizer order from a coal mine in Queensland, Australia, less than a year after commissioning the first.

With the duplication of the crushing circuit, the site now boasts three McLanahan Feeder-Breakers and four McLanahan DDC-Sizers, the company said.

The mine will be processing a maximum of 715 t/h of raw coal through the new McLanahan DDC-Sizers. The secondary sizer will receive minus 250 mm raw coal from the McLanahan run-of-mine (ROM) coal feeder-breaker, with the final washable product size from the tertiary sizer being a nominal 50 mm. This involves no screening between stages, the company said.

Brad Anstess, Coal Specialist for McLanahan, said: “Not only will the customer increase their production, but they will run the equipment in a parallel configuration; that is, having two three-stage crushing modules – ensuring consistency of supply and meeting annual production goals.”

The process will see ROM coal delivered into each ROM receival hopper. Below these receival hoppers, a McLanahan Feeder-Breaker is installed where it will receive a grizzly-controlled top size of approximately 600 mm x 600 mm x 1,000 mm. The feeder-breaker will metre the feed of these large lumps and break them to a nominal 220 mm x 220 mm x 300 mm size, the company said. These nominal 220 mm lumps of rock and coal from the feeder-breaker are then processed by the secondary sizer to a nominal 110 mm and then to a tertiary sizer for a nominal 50 mm product ready for washing in the coal handling preparation plant.

The sizer assemblies were finalised in April this year and each machine was then prepared for the customer who was invited to the McLanahan Workshop located in Cameron Park, New South Wales, the company said.

Each sizer underwent three-and-a-half hours of factory acceptance testing, with vibration and temperature monitored across a range of components including the bearings, motor couplings and gearboxes. “Both the secondary and tertiary sizers ran as expected by the customer, with some minor adjustments made upon test completion,” the company said.

McLanahan Project Manager and Mechanical Engineer, Chris Raines, monitored both sizers for the duration of the factory acceptance tests, and made relevant adjustments to optimise performance on each machine, the company said.

“The McLanahan workshop team took additional care to focus on ensuring roll centre adjustment was accurate as this was important to the client,” Raines said. “The customer is very happy with the finished product. Particularly with the design improvements we’ve made over previous machines.”

The sizers are awaiting shipment from the McLanahan workshop and are due to be commissioned before the June quarter of 2020.