Supplement To Chapter 15 - Maintenance
SUPPLEMENT TO CHAPTER 15:
Maintenance is critical with JIT and TQM implementation. Poor maintenance leads to direct repair
expenses and other expenses resulting from lost production. The production line disruptions are
particularly important in JIT environments. An effective maintenance program ensures that machines
are functioning and performing the operations so that quality of the product is not compromised. An
effective maintenance program can lead to improved capacity, reduction in defects, scrap and rework,
smaller inventories, higher productivity and lower product costs.
Answers to Discussion and Review Questions
The goal of a maintenance program is to minimize the total cost of keeping
facilities and equipment in good working order.
Breakdown costs would include such items as repair of equipment (perhaps
on an emergency basis), lost production, disrupted schedules, parts, possible damage to
product, equipment, and facilities, possible injuries, late deliveries, and loss of morale.
Preventive maintenance may result from inspections that reveal the need for
preventive maintenance, according to calendar (passage of time), or after a set number
Predictive maintenance is an attempt to predict when breakdowns are likely
and schedule preventive maintenance just prior to that time. Generally, such predictions
are made on the basis of historical breakdown and repair records. Consequently, it is
essential to have accurate, up-to-date records on which to base the analysis.
Organizations use some combination of these approaches to deal with
breakdowns: Standby or backup equipment; inventories of spare parts; reliance on
operators to perform some (usually minor) repairs; and well-trained repair personnel.
The Pareto concept is that in any list of factors known to contribute to a
certain result or outcome (accident, injury, equipment breakdown or whatever), a
relatively few factors will account for a disproportionate share of the result (e.g., 90%
of accidents are caused by carelessness). The importance of this is that maintenance
efforts (both preventative and remedial) will be most effective when they are directed
towards those few factors (procedures, equipment, policies, or whatever) that are most
significant, and give much less attention to minor factors.