Metronet, working with Transport for London has the remit to maintain and renew 2/3rds of the Underground network. Metronet is responsible for maintaining, replacing and upgrading the infrastructure on eight of London Underground's eleven lines.
Over two million passengers board Metronet-maintained trains every day. Years of under-investment in the Tube means that a huge programme is needed to renew the world's oldest metro, while continuing to maintain the existing services.
As part of this enormous programme Metronet Railway Engineering Works in Acton are the main engineering centre for the maintenance and repair of traction motors and associated running gear as well as electromechanical systems for braking and pneumatics.
The 13,000 sq.M Workshops in Acton were taken over from the old London Transport in 2004. Since then enormous modernization and quality programmes have been put into place.
The electrical workshop undertakes a programmed cycle of traction motor servicing and repairs. Currently the main activity consists of the refurbishment of the LT130, DC type motors from the Central Line 1992 stock at a rate of 60 per week, plus another 20/30 off traction motors from Bakerloo, Victoria, Metropolitan and District & Circle Lines.
A vital part of the maintenance equipment is Whitelegg Machines undercutter model Betamatik-50T. The undercutting process removes mica insulation between the copper segments, to ensure that the carbon brushes do not come in contact with the mica. Prior to receiving the Betamatik machine, Metronet engineers would perform this process using a hand-held air tool. However, with over 190 segments on the larger armatures, and multiple quantities per week, the Betamatik machine was seen as the only way to cope with the throughput of work, whilst still maintaining the required quality.
The Betamatik machine is able to process armature weights of up to 2500kg and armature diameters of up to 600mm.
Support Engineer at the facility, Richard Watson, followed up an original contact with Whitelegg to source the undercutter and after seeing a similar machine in use at another site chose the Betamatik for its flexibility and work rate.