8/12/2019 MTBS Chart

1/2

8/12/2019 MTBS Chart

2/2

Mean Time To =epair (MTT= Underground Machines

!efinition"

The average downtime for machine stoppages the average duration of downtime events, expressed inhours.

!escription"

%epair planning, management and execution are all factors that contribute to the duration of machineshutdowns. Mean Time To %epair &MTT%' is a performance measure that quantifies repair turnaround time,ie how quicly &or slowly' a machine is returned to service once a downtime incident occurs. MTT% combinesthe effects of inherent machine maintainability ( serviceability and the efficiency of the equipmentmanagement organisation in delivering rapid remedial action in the execution of needed repairs.

#alculation Methodolog$"

MTT= (hours % Total !owntime 'ours *umber of Shutdowns

MTT= used as a benchmar+ for all Underground Products % 9 , hours.

Shutdown count obtained from machine wororder history and dispatch system. )nce again, dispatchinformation must be used to account for shutdown events that are not accompanied by a wor order.

BE*#'M1=>S"

MTT% benchmars vary somewhat by machine model, si*e and design complexity but to a much lesserextent than MTBS, machine age is the primary driver of MTT%.MTT% for new machines should be close to the low end of the range while that of a +mature fleet &one thathas undergone its first round of ma"or component rebuilds' should be close to the high end of the range. Thisis a result of the relative complexity of the repairs seen on a new versus +mature machines.

#xtract from $erformance Metrics for Mobile Mining #quipmentcopyright 2005 Caterpillar Inc. May 2005 version 1.1