文档介绍：TRANSIT MAINTENANCE
Outline
1. Objectives of Maintenance Programs
2. Program Elements
3. Framework for Program Design
4. Maintenance Indicators
5. MBTA Experience
Nigel . Wilson /ESD/227J, Fall 2006 1
Lecture 22
Objectives of Maintenance Programs
• Safety
-- paramount, must avoid unsafe operations if at all possible
-- key question is, are there identifiable precursors to safety
failures?
• Supply
-- mon measure of maintenance effectiveness is % of
scheduled pullouts met
-- a tension between this and reliability on the road
• Reliability
-- mean distance between failures a universal measure of
maintenance effectiveness
-- inconsistent definitions of "failures" parisons hard
•Cost
Nigel . Wilson /ESD/227J, Fall 2006 2
Lecture 22
Program Elements
Maintenance activities can be classified as scheduled
or unscheduled

Daily Servicing
-- fueling, fluid checks, minor maintenance
-- following up on operator defect reports
-- may account for 20% of total maintenance effort
-- early problem identification opportunity
-- vehicle diagnostics puter-based monitoring of
performance
Nigel . Wilson /ESD/227J, Fall 2006 3
Lecture 22
Program Elements
, cont'd
Inspections
-- scheduled check on parts or systems to detect emerging
problems before they result in in-service failure
-- typical inspection program may have 2-5 inspection
intervals ranging from 1,000 to 24,000 miles
-- package each part or system into specific inspection
interval to take advantage of scale economies
-- inspections typically done in off-peak or overnight periods
Nigel . Wilson /ESD/227J, Fall 2006 4
Lecture 22
Program Elements
A. Scheduled, cont'd
Preventive Parts Replacement
-- replace certain parts before failure to avoid high failure
costs
-- integrated into an inspection cycle
-- replacement can