Water pump reliability data

A reliability engineer at an automobile manufacturer wants to improve the reliability of water pumps that the company uses in automobiles. The engineer collects failure data and records when and how water pumps fail. Water pumps were inspected every 10,000 miles.

You can use this data to demonstrate Parametric Distribution Analysis (Arbitrary Censoring) (assume a lognormal distribution) or Nonparametric Distribution Analysis (Arbitrary Censoring). Because the data include multiple failure modes, you can assess the reliability that is caused by different failure modes.

Worksheet column Description
Start The distance at the beginning of the test interval in miles
End The distance at the end of the test interval in miles
Freq The number of pumps that failed within the test interval between Start and End
Failure The cause of the pump failure: Gasket or Bearing

Row 1 indicates that 3 pumps had gasket failures before the beginning of the test. Row 5 indicates that 6 pumps had bearing failures between 50,000 and 60,000 miles.