ONE of Australia's leading suppliers of gearboxes for manufacturing, mining and broad industrial uses was involved recently in a project that will benefit thousands of spectators at Stadium Australia.
Bonfiglioli worked with Structural Systems (Northern) and Eilbeck Cranes to produce for Multiplex a drive system that rolls forward 500-tonne sections of seating to give patrons a better view of events.
The 90m x 30m sections of grandstand on each side of the ground are rolled forward 15.575m before each event, taking less than half-an-hour to move the distance required to put about 7,500 fans on each section much closer to the sidelines and the action.
"The scale of the job and the technology involved is comparable with some of the biggest materials handling tasks ever undertaken in Australian manufacturing or mining, where you sometimes might have to move massive machinery of similar weight and proportion," Bonfiglioli general manager Malcolm Lewis said.
Mr Lewis says the project involved a high degree of technical innovation in the production of a series of 28 gearboxes to operate in two banks of 14 driving bogies for the mobile building structure.
Instrumental in the design and installation were Eilbeck Cranes, who specified the Bonfiglioli drives involved, and Control Techniques, who worked with Bonfiglioli to resolve the technical challenges.
Only a five-month period was available to develop, design, manfacture, install components and commission the stands.
Each gearbox features a 1.1kW four-pole electric brakemotor driving an A series helical gearbox combined with a compact planetary Trasmital gearbox.
The 105kg combination provides high torque within a restricted space, offering a highly cost-efficient and compact installation compared with a much bulkier alternative weighing 261kg.
"The drives operate with a number of technologically interesting features, including electronic encoders linked to PLC-controlled variable frequency drives,” Malcolm Lewis said.
“This arrangement functions to ensure all the motors operate in unison, so the bogies drive smoothly, without imparting any discordant stresses into the structure.
"The Bonfiglioli brakemotor involved was also fitted with a ventilated servo, for ongoing reliability within a restricted space, where maintenance access could be an issue.
"The ventilation was important to ensure reliability, because the drives, controlled by the variator, do not run at their constant design speed - a condition which, without the ventilation, can produce heat,” he added.
A final feature of the arrangement was a micro-switch built into the brakemotor circuit to ensure all brakes are released before startup.
Mr Lewis said the project illustrated the many inputs that went to make up a large-scale industrial motors and drives project - including product range, engineering innovation and ability to deliver from quality-controlled facilities within Australia.