FAP/05026:TE
26 May 2005
Costly machine failure avoided at Australia's most advanced sawmill
A threat to production was averted for timber processing company Auspine recently, thanks to specialist on-site machining equipment and expertise from Furmanite Australia, the speciality services company geared to maximising asset uptime, which enabled costly machine failure and lengthy unscheduled downtime to be avoided.
Auspine operates the largest and most technologically-advanced sawmill in Australia at Tarpeena in South Australia. When the sawmill's bark stripping machine (which moves the logs through a spinning 'doughnut' where blades strip the bark from the logs as they pass through) began to show high vibration readings, it was clear there was a problem that needed to be addressed. Furmanite, known for its in-situ services, was called in by Auspine's on-site bearing specialist SKF to assist.
Investigative work by Furmanite identified the root cause of the problem. A bearing housing face was rubbing on the 'doughnut' slew ring bearing face, and the friction between the bearing and housing was smearing the bearing face and causing the machine surfaces to rub. Indeed, had this problem not been addressed, total machine failure would have been inevitable - resulting in costly downtime and a loss of production at a plant able to process 70 lineal meters of logs per minute.
The large housing and associated bearing and pulley required machining to provide bearing clearance and to restore correct alignment and flatness of all the faces, which ranged up to 1800mm diameter. Furmanite, with its specialist on-site machining expertise, was able to achieve this on-site meeting workshop tolerances.
The first requirement was to assess the extent of machining required by surveying the faces. This was achieved by Optical and Laser and survey by Furmanite technicians, identifying that up to 3mm of material had to be removed from the faces to provide clearance and restore correct alignment of the bearing, pulley and housing.
Furmanite met the requirements, using a portable compact pneumatically-powered flange facing machine, capable of machining flanges from 28 to 72 inches (711 to 1829 cm) in any position, to achieve finishes from 1.6mm Ra to 6.3mm (63 CLA to 250 CLA) when turning, or. 0.8mm RA to 1.6mm (32 CLA to 63 CLA) when polishing.
In performing the laser survey, Furmanite technicians were additionally able to identify misalignment of the support structure of the de-barker housing and associated frame distortion. The mount for the housing now required welded reinforcement and re-machining of the mounting faces by Furmanite to restore alignment of the whole machine. This additional work to realign the de-barker, its mount and frame was also successfully undertaken by Furmanite, despite no reliable datums existing - a challenging task.
Furmanite Australia south central sales manager Chris Ramsden reported: "We were able to correct all the problems for Auspine on-site within the two weeks of their scheduled shut, with three Furmanite technicians working 12 hour days to complete the work."
Auspine's engineering manager Daniel Alexander commented: "We were delighted with the achievement. We've had no further problems with the machine and have avoided the potentially significant consequences of machine failure to the plant. Furmanite was not only able to solve the problems of the bearing and housing but also identify and rectify the unforeseen alignment problems of the frame and mount, all of which is critical to reliable and efficient production."
Further information on Furmanite's wide range of services and technologies geared to maximising asset uptime is available from www.furmanite.com.
For further press information please contact:
Sarah Manwaring-White, Keep in Touch Ltd
Tel: +44 (0)1451 844 488 Email: sarah_mw@keepintouch.co.uk
Issued on behalf of Furmanite Australia