Question 1
As far as maintenance costs are concerned,
◦ preventive maintenance is always more economical than breakdown maintenance.
◦ for high levels of maintenance commitment, breakdown maintenance costs exceed preventive maintenance costs.
◦ Breakdown maintenance is always more economical than preventive maintenance when the "full cost of breakdowns" is taken into consideration.
◦ for low levels of maintenance commitment, breakdown maintenance costs exceed preventive maintenance costs.
◦ for low levels of maintenance commitment, preventive maintenance costs exceed breakdown maintenance costs.
Question 2
For a machine to be a good candidate for preventive maintenance
◦ the consequences of failure must exceed the cost of preventive maintenance and the MTBF distribution must have a relatively low standard deviation.
◦ the consequences of failure must be relatively unknown and, therefore, risky.
◦ the consequences of failure must exceed the cost of preventive maintenance and the MTBF must be relatively high.
◦ the consequences of failure must exceed the cost of preventive maintenance and the MTBF distribution must have a large standard deviation.
◦ the consequences of failure must exceed the cost of preventive maintenance and the MTBF must be relatively low.