TABLE OF CONTENTS In the absence of reliability data, we have to resort to on-site inspection, engineering judgment, and experience in order to arrive at a reasonably consistent and comparable reliability assessment. In a large plant or an organization having many plants, it would be desirable to have a numerical value established to facilitate comparisons of similar equipment and assist in the planning and budgeting of equipment maintenance, engineering manpower support, improvements, or replacements.
In the following examples, we show how a machinery index or complexity numbers may be established by actual field observation in order to assess machinery reliability management needs.
This is a relative number arrived at to represent the reliability of a particular piece of equipment and to relate it to other similar pieces. This index number can be determined for each piece of critical equipment in a process plant. It also is possible to combine these pieces and express an aggregate Reliability Index Number for the system. There would be little value in doing so, however, unless there were other like systems to be compared with it.
Because it is a relative number, we must be consistent in determining the index number for each type of equipment. Some ground rules must be established to guide craftsmen or specialists in judging the factors involved. The optimum condition would be to have one individual in a plant responsible for determining the Reliability Index Number for one type or class of equipment. The next best condition...
