Repair service gets brick manufacturer back in gear
Published: 12 June 2020 - Rachael Morling
The brick crusher at one of the UK’s largest brick manufacturers consisted of a conventional gearbox with a specialist crusher frame featuring a pair of contra-rotating shafts clad with picks. When functioning correctly, material is fed into the in-running gap and is broken down into smaller pieces. The gearbox drives the lead shaft and two spur gears synchronise the pair sharing the power.
Called on to bring their gearbox expertise to the repair and refurbishment of the brick crusher, Dana’s servicing team examined the unit and found that the driven crusher shaft had lost the splined interface with its timing gear. The shaft itself is a large piece of steel with a lot of machined features and would be expensive to replace. So, Dana decided on a keyed fit with three keys at 120° and an interference fit. The timing gears were worn, but the company was able to take the secondary item and turn it to its better flank and reuse it. The replacement for the scrapped item was made to suit the centre distance and modified to limit the backlash that would be caused by wearing it in with its mate. The whole interface between the output shaft and the crusher was badly worn, requiring re-boring and new oversize bearing cassettes to the driven end of the crusher frame.
For this project, the engineers focused on minimising disruption and reusing parts where possible.