Really big wormwheel gearboxes from Renold Gears.

With a combined weight of almost 25 tons, Renold Gears, Manchester, UK, has manufactured the heaviest pair of wormwheel gearboxes in its history. Designed for installation in an existing Asian steel mill, the gear units will be used as the main drives of a screw-down mechanism that's used to reform newly cast steel billets into thinner width sections. The gear units are driven by massive 220 kW motors as they squeeze steel into the required widths.

The units, a single reduction worm gear design with a reduction ratio of 21.5 to 1, are designed with a huge tooth thickness to withstand in excess of 530,000 Nm static torque. They are manufactured in pairs and are identical externally, but internally the gears are cut with opposite angle gearing known as left and right hand threads. For more information, visit www.renold.com.