1. CHAPTER 6 THE TRAIN

4. Couplers Federal Safety Appliance Act of 1893 required standardization for safety reasons Link-and-pin required going between cars Swinging-knuckle design chosen for standard Two types: E and F

5. Draft Gear Used to cushion shock and strain on cars from movement Friction in system absorbs energy Most have a coupler travel of 5½ in., but some cars (mainly boxcars) have 9½ in. of give.

6. Braking

7. Braking (continued)  Air Brakes  Dynamic Brakes  Independent Brakes

8. Braking System Comprised of: -Brake pipe (connected by hoses between cars) -ABDX valve (triple valve) -Auxiliary reservoir -Emergency reservoir -Brake cylinder Fail-Safe System

9. Braking System (continued) Brake pipe and system charged with air to 70-90 psi (110 psi on passenger trains) Once charged, all brake valves in “release” position Some leakage will occur such that each successive car will have less pressure This is called “brake pipe gradient” and must be less than 15 psi for entire train

10. Applying Brakes Engineer reduces pressure in brake line Brakes apply on car next to locomotive Reduction in air pressure travels through train, one car to the next Can take several seconds for “signal” to reach end of train Slack Action

11. EOT End-of-Train (EOT) device monitors brake pressure at the end of the train and train movement and radios information to locomotive cab If equipped with two- way communications, can be used to apply brakes from rear of train

12. Electronically Controlled Pneumatic (ECP)Brakes Electronic signal activates brakes on each car nearly instantly (speed of light) Flaw: Every car on the train must have wiring and electronic controls

13. Train Dynamics L/V Ratio Train-Dynamics Analysis -Simulators -Cab Displays

14. Vehicle/Track Dynamics – Cab Displays

15. Positive Train Control