SKEDSOFT

Zone 1 — Early Failure Period

It is characterised by a high initial failure rate, gradually dropping off to a low failure rate. By the end of the failures in this zone are due to one or more of the foll
assignable causes :

1. Design deficiency

2. Manufacturing error

3. Raw material defects

4. Wrong maintenance practices.

Zone 2 — Random Failure Period

It is characterised by a more or less constant failure rate. This is the rate at which the normal usage of the product occurs without any expectation of failures.
Failures in this zone are due to chance causes.

Zone 3 — Wear Out Failure Period

It is characterised by a gradual increase in failure rate.

Failures in this zone are due to one or more of the foll :

1. Ageing

2. Reduction in physical strength properties

3. Wear and tear.