Subway trains occasionally appear in tunnels and when entering stations
There is a situation of "sudden braking".
Some passengers raised doubts
No! No! No!
In fact, this is the individual equipment of the subway train in some special conditions, such as the braking of the subway train, wheel-rail friction, etc.
Today, Tie Tie will take you with you
Uncover the root cause of these "odors".
Where does the "burnt taste" come about?
Q: How many common braking methods are there in the subway?
A: Electric brake and air brake. Among them, electric braking is divided into feedback regenerative braking and resistance braking.
Q: How does the train slow down?
A: If the train needs to slow down slightly when running at high speed, the electric braking of the train intervenes first, and the regenerative braking can convert the kinetic energy of the train into electrical energy and feed it back to the catenary.
Since the resistance is located at the bottom of the tram, it is inevitable that dust and other impurities will adhere to the tunnel operation, and the maximum temperature can reach 300 °C, and the attachment will emit a "burnt" smell under the high temperature.
Brake pads are similar to the brake pads on a car, which produce a certain amount of smoke under high-speed friction and a burnt smell from the bottom of the car.
The burnt smell mainly occurs during the process of the train entering the station, which is a normal phenomenon and there is no need to panic.
What else can produce a "burnt smell"?
In order to ensure that the temperature of the carriage is suitable after the winter every year, the staff will turn on the electric heating to heat the carriage.
Since the electric heating is located under the seats in the passenger compartment of the carriage, it is inevitable that some dust will adhere to the resistance wire, and occasionally some burnt smell will be emitted when the electric heating is working.
Will the "burnt smell" affect the operational safety of the subway?
For wheelsets, brake shoes, electric heating, etc., vehicle maintenance personnel will be included in the daily maintenance project for dynamic management in the form of data detection and special operations.
Tips
If you encounter or have other emergencies during the ride, you can also get in touch with the driver in time through the "emergency alarm" device in the car.