At its Wacol operations, Tomlinson has manufactured key elements for the new Bucyrus 8750 dragline, under licence from the OEM, to be delivered to the Ensham opencut.

 

According to RCR Tomlinson’s July newsletter, the work being performed at Wacol consists of several distinct items:

 

Tri-Structure Deflection Sheave

 

This component attaches to the front of the dragline and has ropes passing through it to control the drag and hoist of the bucket. It was originally specified as three separate parts; however, Bucyrus sought RCR’s suggestions for fabricating it as a single item to reduce the amount of site welding required.

 

Weighing 50 tonnes, the 27m x 4.5m component was delivered on time – but only after removing the fence at RCR’s premises.

 

Gear Blanks – Drag & Hoist Gears

 

The contract included fabrication of two 4.6m diameter gear blanks, each weighing 23t. The gears are mounted on the rope drums and control the dragline’s drag and hoist operations.

 

To reduce the lifting and manoeuvring requirements, the Wacol team developed an innovative process that eliminated the need to rotate the gear blanks themselves. Final machining was performed by a gear cutting contractor, with the units delivered ahead of schedule.

 

Boom Point Structure

 

The 10m long, 32t boom point structure is positioned at the top of the dragline’s boom and acts as a pivot point for the hoisting of the bucket. This item was machined using RCR’s Horizontal Borer, manufactured fully in-house and delivered on schedule at the end of May.

 

Tri-Structure Heads

 

These items are located at the top of the dragline and connect the boom and tri-structure together.

 

Two of the 21.5m, 39t components (left- and right-hand versions) are currently being fabricated and machined at RCR’s workshop, with assistance received from RCR Austheat in straightening metal plates before fabrication commenced. These are scheduled for delivery at the end of June.

 

Back Legs

 

The 54m long, 64t back legs pin the tri-structure to the back of the dragline to maintain its balance when operating. As with the tri-structure heads, left- and right-hand versions of the legs are presently being fully fabricated and machined in-house.

 

Delivery is scheduled for July, with each leg to be supplied in three sections for ease of transport and handling.