M_boy

  What is Disc Brakes? In a disc brakes system, braking is performed by pressing brake pads against a disc, which is rotating with the wheel.and brakes is applied on the wheel, and vehicle is deaccelerate and vehicle is stopped. Working The brake disc is made from cast iron and is bolted to the wheel hub and rotates with the wheel. the is suspended over the disc. The caliper body is mounted on the caliper bracket using two slide pins. the caliper bracket is attached to the Knuckle. a piston is attached to the caliper body and held in place by the piston seal and piston boot. the brake pads are placed in between the piston and disc , and are held in position by pad retainers on the caliper bracket. The passages are drilled in the caliper for the hydraulic fluid to enter or leave the caliper body.these passages are also connected to one another for bleeding. when the brake pedal is pressed, hydraulic pressure enters the caliper's cylinder ,resulting in the piston being pushed out fro...

   What is Drum Brakes? Drum Brakes system Consists of a pan Shaped Drum, it have two brake shoes, a backing plate and a wheel cylinder or an operating cam (mechanical linkage). A drum brake is a brake that uses friction caused by a set of shoes or pads that press outward against a rotating cylinder-shaped part called a brake drum.                  Function of Drum Brakes BRAKES SHOES BRAKE LINING BACKING PLATE BRAKE SPRINGS BRAKE DRUM LEADING SHOE AND TRAINING SHOE WHEEL CYLINDER SELF ADJUSTER LEVER ADJUST SPRING SHOE LOWER RETURN SPRING Working The Drum is attached to the axle or Hub flange, just inside the wheel, and it rotates directly with the wheel. The brake shoes just inside the wheel, and it Rotates directly with the wheel. the brake shoes are positioned just inside the drum and are mounted on the backing plate.the outer surface of the shoes are lined with the friction material, to increase frictional coefficient. They are ...

 What is Braking System? The brakes cause the vehicle to decelerate or stop and also hold the vehicle in position while stationary. when the brakes are applied to a moving vehicle, the kinetic energy of the vehicle is transformed into heat generated by the friction. The Heat generated is dissipated  to the surrounding air. Classification of  Braking System:  1.) According to the Purpose of Brakes. (a) Service or Foot brake (b) Hand brake or parking brake The Service brakes are the main brakes, operated by the foot pedal and are used while the vehicle is moving. The Parking brake is operated mechanically by parking brake level or pedal, and it is used to hold the vehicle in position while stationary.It is used during parking so that the vehicle may not roll off due to road gradient or fast blowing wind. it is also used in emergency when the service brake fails or proves ineffective. It may be noted that due to its use during emergency, it is also known as emergency...

What is Supercharging?  The method of increasing the inlet air density is called Supercharging . "MORE FUEL + MORE AIR = BIGGER EXPLOSION = GREAT HORSEPOWER" Supercharging can be done both for SI engine as well as in CI engine. The purpose of supercharging an  engine is to raise the density of the air charge, before it enters the cylinders. Thus, the increased mass of air will be inducted which will then be compressed  in each cylinder. This makes more oxygen available for combustion than the  conventional method of drawing the fresh air charge into the cylinder . Consequently, more air and fuel per cycle will be forced into  the cylinder, and this can be effectively burnt during the combustion process  to raise the engine power output to a higher value than would otherwise be  possible. Supercharging of an engine can be done using either one of the following components: 1.)SUPERCHARGERS 2.)TURBOCHARGERS  If the supercharger is driven by the engi...

METHODS OF SUPERCHARGING: (i) Independently driven compressor or blower, usually driven by an electric  motor. (ii) Ram effect. (iii) Underpiston supercharging. (iv) Kadenacy system (applied to two stroke engines). (v) Engine driven compressor or blower.   Electric Motor Driven Supercharging: In this type the compressor is driven independently usually by an electric motor. The speed of the supercharger can be varied independent of engine  speed and therefore control is comparatively easier. Ram Effect of Supercharging: The ram effect of supercharging system consists primarily of tuned inlet pipes. These pipes induce resonant harmonic air oscillations. The kinetic energy of  these oscillations provides a ramming effect. For the efficient operation of this  system, the engine speed must be kept constant. Under Piston Supercharging: Under piston method of supercharging has so far been confined to large marine  four stroke engines of the cross head type. It uti...

Types of Supercharging:     (i) Centrifugal type: The centrifugal type supercharger is commonly used in automotive engines.   A V-belt from the engine pulley runs the supercharger. First, the air-fuel mixture enters the impeller at the centre. It then passes through  the impeller and the diffuser vanes. Finally, air or mixture enters the volute  casing and then goes to the engine from the casing. The mixture will come  out at higher pressure and this condition is called supercharged condition. Because of higher pressure more air-fuel mixture is forced into the cylinder. About 30% more air-fuel mixture can be forced into the combustion chamber. The impeller runs at very high speeds, about 80,000 revolutions per minute. Therefore the impeller should be able to withstand the high stresses produced  at this speed.  Impellers are usually made of duralumin, or alloy steels, to withstand the high stresses.       (ii) Root’s type: The ...

How to Measure Cylinder Liner Bore Wear? A liner diameter measuring instrument along with a standard template rod is used to measure liner dimensions. Generally while taking the measurement the temperature of the liner and micrometer should be kept at the same temperature . If the temperature exceeds than that of the liner or vice versa then the readings have to be corrected by multiplying the value with the correction factor and deducting the value obtained from the reading taken.  The wear rate will be different inside the liner. The wear will be more in the top one-third part as combustion takes place there and temperatures and pressure are also very high at the top. Procedure: 1. After engine is shut down and cooled, open the cylinder head and remove the piston 2. Cover the stuffing box hole to avoid debris falling inside crankcase 3. Remove the liner ring and clean the carbon deposits from top surface of the liner 4. Insert a ladder and carefully inspect the liner surface...