Vaishali Express - जितना सुंदर तुम्हारा नाम उतनी सुंदर तुम्हारी चाल - be my valentine - Rahul Vatsa

Yo, listen up! So, there's this thing called Main Reservoir (MR) on a train. The dude in charge, aka the engineer, uses a compressor to fill it up with air at 125-140 psi. When the engineer wants to release the brakes, air gets into the train pipe through the brake valve. For freight trains, the brake pipe is usually around 70-90 psi and for passenger trains it's 110 psi. When the engineer pulls the brake handle to the "service" position, the pressure in the train pipe drops and the brakes get applied. Oh, and by the way, there's also something called Brake Cylinder (BC) that stores compressed air only for stopping the train.