An Efficient Failure-Based Maintenance Decision Support System for Smalland Medium Industries - Efficient Decision Support Systems: Practice and Challenges from Current to Future - page 205

operation (high downtime). Machines in this region should be monitored closely. It
is a good idea to equip the machines with sensors or any condition-based
monitoring devices to observe their performance;

d. Design-out maintenance (DOM): Machines that always fail (high frequency). Once

failed, it takes a long time to bring them back to normal operation (high
downtime). This region consists of the worst production machines and it is
recommended that they be structurally modified. A maintenance department
should consider a major design-out project and spend money to upgrade the
machines in this grid; and

e. Fixed time maintenance (FIM): There are five categories as follows:

 FTMI: Concern about the timing of the maintenance. Maintenance department
should revise when is the best time to conduct the preventive maintenance;
 FTM2: Maintenance department should study who is the most suitable person
to conduct the maintenance job for those machines in this grid, i.e. operator,
technicians, contractors or maintenance engineers;
 FTM3: Failure frequency and downtime are almost at the moderate cases,
 FTM4: Maintenance department should revise on their maintenance checklist
and instructions. What are the instructions that must be included during
maintenance; and
 FTM5: Maintenance department should revise on how the maintenance should
be conducted and improved.
The TPM approach should be applied for the lower triangle of the DMG matrix, as
shown in Table 2 (Labib, 1998b). TPM is applied globally and one of the TPM
concepts is to empower the operators to maintain continuous production on totally
efficient lines (Nakajima,1988). TPM is the continuous knowledge transfer to
operators and the maintaining of the production equipment together with the
maintenance crew. Hence, we can slowly reduce the waiting time for technicians to
be in the production plant. On the other hand it gives operator the opportunity to
eliminate the root causes of the machines' errors on a small level, before they
become big ones.

Table 2. DMG-TPM Strategy (labib 1998b)
The RCM approach should be applied for the upper triangle of the matrix as shown
in Table 3. RCM involved a study and measurement of the probability that a
machine will operate as expected at the desired level, for a specific period of time,
under the design operating conditions, and without any failures. Once the
problematic machines are identified, the maintenance strategy should be adjusted
to ensure the longest survival of the machine to complete a mission at a specific