How was the break works in train without grip?

Question

brief explanation about breaking system in train

Answer 1

the conventional brakes on a standard locomotive are genrally operated by air the same as a truck the harder the brakes are applied the more pressure is put onto the wheels some areas of the world where they have had trains runaway due to to much friction on the wheels and the track,s which in turn have caused the wheels to actually melt..

Answer 2

Mayank is on the right track (no pun intended).

The brake system is a pneumatic system.

Actually quite complicated, but briefly put, the brake system is charged with air from the compressors on the locomotives.

Once charged, the control valve on each car is told to go into application position, by creating a difference in air pressure through the air line that runs the length on the train.  This is called the "brake pipe."

By letting air out of the brake pipe, the control valve senses the pressure drop and moves to allow internal ports and passages to connect to let air flow from the cars' auxiliary air reservoir into the brake cylinder.

The cylinder comes out and pushes on the brake rods, which move the brake beams on the cars trucks, which in turn puts the brake head with the brake shoe against the wheel, providing retarding effort.

When desiring to release the brakes, the pressure in the brake pipe is increased, causing the control valve to move again, exhausting the air from the brake cylinder, when internal springs cause the brake rigging to retract.

At the same time, air is also used from the brake pipe to re-charge the reservoirs on each car.  After the air reservoir is recharged, the valve returns to it neutral position, called the "lap position."

This is how Westinghouse Air Brakes work, but other systems are similar, however all trains in North America use this system, and it is wide spread through the rest of the world as well.

Most modern passenger equipment works the same way, except for instead of having brake shoes push against the wheel, they are equipped with what are essentially disc brakes, just like on your car, only on steroids.  This is why they can operate at speeds anywhere between 125 to 250 MPH or more, and still have a chance of getting the thing stopped where ya want....

Here's a handy bit of trivia.  If the energy potential in the train's air brake system could be changed from retarding effort to propulsive force, each train has enough to put that train into orbit.  And that ain't no bull.  

Gettin' 'em goin' is the easy part.  Gettin' 'em stopped is the b*tch...  That is why, if I'm on my train clickety-clackin' along, if I can see you, it is already too late to stop for you, and I sure can't go around you.  Stay in the clear = stay alive and in one piece..  It's just that simple.

Good question. Thanks for asking.

Answer 3

the train wheel is metal and next to it is an metal shoe that when the air brakes applied by engineer the shoe makes contact with wheel and stops it. this happens at the engine and all cars when air brakes applied the air presser is what moves the shoe.

another way to think about it is that willie you are pushing your grocery cart and you want to stop it so you put the sole of your shoe against the wheel and it stops. same thing except mechanical.

Answer 4

They are vaccum brakes.

the brakes are held away from the wheels due to the vaccum.

When the brakes are to be applied, the vaccum is neutralized and the brake shoes cling to the wheel, thus creating a braking effect.

the brake shoes are made up of some metal.

But they stick sooo hard that they can create enermous amount of friction...

this is what i've heard about the train's braking system.

I'd reccomend that you get it confirmed from somewhere tho'

Answer 5

This is much easier to explain with pictures and diagrams.  Try an internet search on "westinghouse air brake."

There are high-temperature metallic brake shoes that are applied to the running surfaces of the wheels by compressed air cylinders, and the cylinders on each car are provided with compressed air through a control valve from a separate compressed air reservoir on each car.

The control valve is operated in turn by remote control from the locomotive cab by the brake valve that is operated by the engineer.  This system also uses compressed air, and both controls the brakes and keeps the reservoirs filled.

The control system is arranged in what is called a "fail-safe" mode, which means that if it fails, it goes into a safe state.  In trains, what that means is that the control valves that operate the brakes on individual cars are made so that increasing the air pressure in the train line releases the brakes, and decreasing it applies the brakes.

Thus, if the train breaks in two, the brakes are automatically applied.  "Fail-safe."

Answer 6

There are a few methods. As said above there are disc and tread brakes but there are a few others that work without clamping things to the wheel.

Firstly there is engine braking, this tends to be used in small rail-cars with mechanical or hydraulic drive, this is where the transmission and engine are used to slow the train. In the UK its fitted to Cl. 175s and possibly the similar Cl. 180s.

In a similar vein there is Rheostatic braking, this is used in trains with electric drive, the motors are used as generators with the power generated dissipated in grids of resistor. In the UK the 22x 'Voyager' family of high speed diesel units use this system to slow down, with conventional disc brakes taking over at low speeds, this is auidible to passengers as a high pitched wine...

A version of this exists in electric trains but the power generated is fed back into the power supply for use by other trains if it is set up to do so.

Finally there are eddy brakes, these use powerful electromagnets underneath the train to act on the track and slow the train down. This is used by German high speed trains and can cause problems when operating in other countries (eg on TGV lines in France)

Answer 7

You can also have Air brakes they wore used in the UK where air was used to brake the train but Vacuum brakes wore mainly used in the UK they controlled the whole train if the vacuum was cut the brakes would apply