Brake reliability data

A reliability engineer wants to compare the failure rate for two different types of a brake component that is used on subway trains. The engineer collects replacement time data and component type for 29 trains. Each time a unit failed, it was repaired and returned to service.

You can use this data to perform a repairable systems analysis and to demonstrate Nonparametric Growth Curve.

Worksheet column Description
ID The train identifier. 29 trains were sampled.
Days The number of days until brake component replacement. The final time for each train is the final failure for that train.
Type The component identifier: 1 or 2.

Data on train 112 is contained in rows 3-6. Train 112 had component type 1. The first component replacement was done at day 364, the second component replacement was done at day 391, the third component replacement was done at day 548, and the final brake failure happened at day 724.