Compare hydraulic brakes to air brakes?

Answer 1

Typically the fluid used in hydraulic breaks is used to push the brakes closed and so the fluid has to be able to withstand the heat generated by braking. Push the brakes, fluid moves towards (in the direction of) the brake pads and disks, heats up and...we hope it doesn't boil! Brake fluid is engineered to withstand that heat. If a leak develops in the brake system or a bubble of air is introduced into the system, the ability of the vehicle operator to produce pressure on the disk is minimized or eliminated completely. Leaks in hydraulic brakes are catastrophic.

Air brakes, in general, are built such that air pressure holds brake parts away from the moving parts. When the vehicle operator presses the brake pedal, the air is released allowing springs or some other device to force the brake pads into contact with the rotating disk. Hydraulic brakes are fail safe (if you lose air pressure the brakes are applied and you have to restore pressure to move the vehicle - that is why trains tend to use air brakes). Air brakes also require a relatively large air compressor, more and bigger air lines instead of the tiny hyrdraulic lines you'll find on a car. Hydraulic systems tend to be lighter and smaller.

Answer 2

In a vehicle with hydraulic brakes when you step on the brake peddle it pushes fluid thru the brake lines which forces the brake shoes onto the drum or caliper to apply the brakes. With air brakes like a semi when the system is depressurized ( no air in system) the pads are pushed tight against the drums. When the driver releases the parking brakes they are putting air into the system counteracting the force of the springs holding the shoes to the drums and pulling the shoes off the drums. (bear with me) When the driver pushes the brake peddle it releases some of that air allowing the shoes to contact the drums again applying the brakes. This is so if you lose all air pressure the brakes lock up. Older trucks (pre 70's) were built opposite so if you lost air you had no brakes

Answer 3

YAP.the sandman,just say it like it is. no much to add from my part. Hydraulic.....pedal ,push rod,master cylinder,hydraulic pressure in a tubing,caliper piston, brake pad, rotor. Air ...pedal,throttle air valve(receive air from tank and send air to relay valve) relay valve(when receive air supply from throttle valve open the air supply from the tank to a chamber) brake chamber (has a diaphragm and a push rod in it) receive air from the tank to push a rod that is connected to slack adjuster(is a lever)the slack adjuster make rotate an axle at which the other end has an "S" shape ,when "S" cam rotate push the brakes pad against the wheel drum.

Answer 4

hydraulic breaks use fluid which is less compressible then gas.. air breaks are using gas (air=gas)

i don't know what else you want to know