Expand mobile version menu

Real-Life Activities

Real-Life Math

Locomotives are massive, powerful machines. But to run properly, they must be maintained to exact specifications. That means using measuring devices such as calipers and even micrometers to get things exactly right.

But locomotive mechanics use math in many other ways during the day. One common way is to estimate the time and cost of repairs. Even though most mechanics work in-house, this information is important because it tells managers when a repair is worthwhile and when it might be time to retire or scrap an engine.

Engine 501B was built in 1971. It has 1,500 hours of time on the engine, about 2/3 of which is idle time (1/3 drive time).

You complete an inspection and determine that it needs the following work:

  • Replace engine valves
  • Replace engine piston sleeves
  • Replace all hydraulic lines

The cost of each is as follows:

Valves: 24 valves at $120 per valve
Time: 15 minutes per valve

Piston sleeves: 12 sleeves at $45 per sleeve
Time: 20 minutes per sleeve

Hydraulic lines:
120 meters of hose at $2 per meter
Time: 1/2 hour per 10 meters

Labor is priced at $50 per hour.

The average locomotive engine has a life expectancy of 750 drive-hours. Each drive-hour is valued at $100. Is it worth it to repair this engine?

Contact

  • Email Support
  • 1-800-GO-TO-XAP (1-800-468-6927)
    From outside the U.S., please call +1 (424) 750-3900
  • North Dakota Career Resource Network
    ndcrn@nd.gov | (701) 328-9733

Support