5 In the future engineering equipment will be even more computerized and complex.
Further computerization of equipment will increase the importance of software maintenance significantly, approaching, if not equaling hardware maintenance. In
addition, factors such as increased computerization and complexity will result in greater emphasis on maintenance activities with respect to areas such as cost effectiveness,
quality, safety, and human factors [2]. In the future creative thinking and new strategies will definitely be required to realize all potential benefits and turn them into
profitability.
2.2.1 History of
Maintenance
Although humans have felt the need to maintain their equipment since the beginning of time, the beginning of modern engineering maintenance may be regarded as the
development of the steam engine by James Watt 1736-1819 in 1769 in Great Britain [4]. In the United States the magazine Factory first appeared in 1882 and has played a
pivotal role in the development of the maintenance field [3]. In 1886 a book on maintenance of railways was published [5].
In the l950s the term preventive maintenance was coined, and in 1957 a handbook on maintenance engineering was published [6]. Over the years many other developments in
the field of engineering maintenance have taken place, and today many universities and other institutions offer academic programs on the subject.
6
2.2.2 Maintenance Engineering Objectives
There are many objectives of maintenance engineering. Some of the important ones as shown in Figure 2.1 [7].
Figure 2.1: Important objectives of maintenance engineering.
2.2.3 Facts Related to Engineering Maintenance
Some of the facts and figures concerning engineering maintenance are as follows:
1. U.S. industry spends over 300 billion annually on plant maintenance and
operations [8].
7 2.
It is estimated that the cost of maintaining a military jet aircraft is approximately 1.6 million per year, and about 11 of the operating cost for an aircraft accounts
for maintenance activities [9]. 3.
Over the years the size of a plant maintenance group in a manufacturing organization has varied from 5 to 10 of the total operating force [10] — 1 to 17
persons in 1969 and 1 to 12 persons in 1981 [10]. 4.
For fiscal year 1997, the request of the U.S. Department of Defense for their operation and maintenance budget was 79 billion [11].
5. In 1970 a British Ministry of Technology Working Party document reported that the
United Kingdom annual maintenance cost was around 3000 million pounds [12,13]. 6.
The U.S. Department of Defense spends approximately 12 billion annually on depot maintenance of weapon systems and equipment [14].
2.2.4 Safety in Maintenance
