CHAPTER 6 THE TRAIN. Couplers Federal Safety Appliance Act of 1893 required standardization for...
-
Upload
tatyana-brundrett -
Category
Documents
-
view
215 -
download
0
Transcript of CHAPTER 6 THE TRAIN. Couplers Federal Safety Appliance Act of 1893 required standardization for...
CHAPTER 6
THE TRAIN
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
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.
Braking
Braking (continued)
·Air Brakes
·Dynamic Brakes
·Independent Brakes
Braking System
• Comprised of:
-Brake pipe (connected by hoses between cars)
-ABDX valve (triple valve)
-Auxiliary reservoir
-Emergency reservoir
-Brake cylinder
• Fail-Safe System
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
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
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
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
• Train Dynamics
• L/V Ratio
• Train-Dynamics Analysis-Simulators-Cab Displays
Vehicle/Track Dynamics
– Cab Displays
Positive Train Control
Positive Train Control
Positive Train Control