The lifting mechanism is chain driven. To change the bearings the whole mechanism has to be dismantled. This causes downtime of up to two days.

Due to this lengthy downtime when changing the 1218K bearing and H218 sleeve the plummer blocks were altered to use a Vesconite split bush (OD 110 mm x ID 60 mm - 25 mm long)(OD 4.3" x ID 2.4" - 1" long).

This change to a Vesconite split bush resulted in the following improvements:

• Longer life - had been in operation for over four years at time of reporting
• Less downtime - estimated at under an hour to change the bushes in the future
• Reduced lubrication
• Substantial savings on bearings and bogey wheels