Wednesday, March 30, 2011

STUDY OF TWO-WHEELER CHASSIS DYNAMOMETER

AIM:
To study of two wheeler chassis dynamometer.

APPARATUS REQUIRED:
Two-wheeler chassis dynamometer.

DESCRIPTION:

Chassis Dynamometers: This is a model concept for total electronic testing of two-wheeler chassis dynometer for motorcycles, scooter, mopeds etc. The chassis dynometer simulates the driving conditions on road in a control environment. This has many distinct advantages of testing various parameters of two-wheelers, the most important one is the possibility of testing complete vehicle performance or engine performance as installed. There is no necessity to take engine out from the vehicle.
Use of chassis dynamometer allows the test engineer to simulate road load conditions in laboratory and it can be termed as ‘all weather road’ for the test vehicle. The road load on the vehicle can be put on the engine on a chassis and quick results can be obtained.

RESULT:
Thus the study of two wheeler chassis dynamometer is completed.

PERFORMANCE TEST OF A SHOCK ABSORBER

PERFORMANCE TEST OF A SHOCK ABSORBER

AIM :

To study the characteristics of a shock absorber.

APPARATUS REQUIRED :

Shock absorber test rig

OBJECTS OF THE SUSPENSION ARE :

1. To prevent road shocks from being transmitted to the vehicle components.
2. To safeguard the occupants from road shocks.
3. To preserve the stability of the vehicle in pitching or rolling in motion.

MAIN FUNCTIONS OF SHOCK ABSORBERS :

1. To control quick bouncing of wheels on road surface.
2. To control slow bouncing of the body on the suspension springs.

DESIGN CALCULATION :

1. Diameter of the piston (dp)
Piston of diameter, dp =                     mm.

1. Diameter of the rod (dr)
The diameter of the rod, dr   = 0.4 * dp

1. Outer diameter of shock absorber (D) (Dust cover)
Diameter (D) =                        mm.

1. Determination of design compression force (Fc)
Compression force, Fc = [Ap – Ar]* Pc
= π/4[dp2 – dr2]*Pc
Ap- Area of piston in m2
Ar- Area of rod in m2
Pc- Pressure transmitted through shock absorber during compression in N/m2 (0.05 to 0.25 MPa)
1. Determination of design rebound force (Fr)
rebound force, Fr = Ap* Pr
= π/4[dp2]*Pr
Pr - Pressure transmitted through shock absorber during rebound in N/m2 (0.5 to 1 MPa)

1. Determination of damping coefficient:

Compression
Kc   =                                        N-s/m

µ- Flow co – efficient
υ- Density of fluid in (9000) N/m3

RESULT:
Thus the characteristic of a shock absorber has been studied.

PERFORMANCE TEST ON COIL SPRING

PERFORMANCE TEST ON COIL SPRING

Ex.No. 7
Date :

AIM :

To determine the following properties of a coil spring.
1. Stiffness of the given coil spring.
2. Modulus of rigidity.

APPARATUS REQUIRED :
Spring testing machine, coil spring, vernier caliper.

PROCEDURE :

1.      The spring is placed centrally over the lower plate slowly rotate the plate handle.
2.      Measure the thickness of spring and calculate the number of turns.
3.      Measure the outer diameter and inner diameter of spring using vernier caliber.
4.      Keep the spring in such a way that top and bottom plate just touches the spring.
6.      Note the deflections reading on the gauge apply the load on the spring and note the deflection reading.
7.      Note the deflection while unloading and also get the average deflection.
8.      Plot the graph between load and deflection.
9.      The deflection of a spring is obtained from the help of the graph.

CALCULATION :

Formula,
Modulus of rigidity   G= [(64nWR3)/ (δd4)]   N/mm2
where,
W - Load applied in N
δ – Deflection in mm
R – Mean coil radius of given spring in mm
d – Diameter of the spring wire in mm
n – Number of turns in the given spring
Stiffness of the spring   k = (W/δ)      N/mm
Mean radius  R = [(do-t)/2]     mm
do – outer diameter
t – Thickness

RESULT :

Modulus of rigidity of spring =                      N/mm2
Stiffness of spring                   =                      N/mm

TABULATION :

 MSR (mm) VSC (mm) TR = MSR+ VSC*LC Outer diameter (do) Thickness (t)

DIAGRAM:

THREE WHEELER BRAKE AND CLUTCH PLAY ADJUSTMENT

THREE WHEELER BRAKE AND CLUTCH PLAY ADJUSTMENT

AIM :

To adjustment of brake and clutch as per specification.

TOOLS REQUIRED :

Tool set.

DESCRIPTION :

Three wheelers use hydraulic operated foot brake on the two rear wheels with an additional hand brake mechanically operated on the front wheel.
In hydraulic brakes, care must be taken that not even small quantities of air enter in to the braking system. The air being compressible, it gets compressed when the brake pedal is pressed. The result is that fluid pressure is not transmitted to the brakes. Which, as a consequence, are not actuated.
Due to the continuous use of the brakes, wear take place of the brake lining, linkage etc., which necessitate periodic inspection of the braking system and to make suitable adjustment. The brake adjustments can be broadly divided in to two types, viz, the minor and major adjustments.
Minor adjustment mainly includes the adjustment of brake shoes to compensate lining wear and is done without removing the wheels. A major adjustment on the other hand, has to be done after installation of new shoes or relining the old shoes.

PROCEDURE:

The procedure of driving air out of the braking system is called bleeding. A special bleeding valve is provided for this purpose on the back plate. For bleeding, the master cylinder is topped up completely with the brake fluid and a pipe is connected to the bleeding valve. The other end of this pipe is dipped in the brake fluid contained in some jar. One person sits on the driver’s seat and presses the brake pedal, after which the bleeder valve is opened by the second person, when some air bubbles will come out of the pipe and escape through the brake fluid in to the atmosphere.
The bleeder valve is now closed and the brake pedal released and pressed once more after which the bleeder valve is opened again when some more air bubbles will come out. This procedure is repeated till on pressing the brake pedal, no more air bubbles are noted. Now with the pedal in the pressed position in the bleeder valve is closed.
To perform minor adjustment, on turning the adjustment nut the cam is also turned. This cam is fitted on the brake shoe and the adjusting nut is provided on the back plate. Turning this nut with spanner in the clockwise direction causes the shoes move closer to the brake drum.
To perform major adjustment, remove all brake drums and inspect linings and drums. If the drums are worn out, turn them in case the damage is with in limits or else replace them. In case of linings having reached upto within 1mm of rivet heads, remove the same and reinstall the new ones.

DESCRIPTION :

Clutch assembly is fitted between engine and gearbox. The purpose of the clutch assembly to transmit power of the engine to the rest of the transmission system, by disconnecting & connecting the power is required.

The only adjustment required in a clutch is of the free lever play, which is necessitated on account of wear of the friction lining due to continuous use or with the wear of the throw out bearing carbon ring due to the habit of the driver to press his hand always on the clutch lever. The wear of the friction lining decreases the free lever play. An adjustment nut is provided at the lower end of the clutch lever. To slacken the lock nut first, make the desired adjustment with the adjusting nut and retighten the lock nut.

RESULT :

Thus the adjustment of brake and clutch as per specification is performed.

TWO WHEELER BRAKE AND CLUTCH PLAY ADJUSTMENT

TWO WHEELER BRAKE AND CLUTCH PLAY ADJUSTMENT

AIM :

To adjustment of brake and clutch as per specification.

TOOLS REQUIRED :

Tool set.

DESCRIPTION :

Due to the continuous use of the brakes, wear take place of the brake lining, linkage etc., which necessitate periodic inspection of the braking system and to make suitable adjustment. The brake adjustments can be broadly divided in to two types, viz, the minor and major adjustments.
Minor adjustment mainly includes the adjustment of brake shoes to compensate lining wear and is done without removing the wheels. A major adjustment on the other hand, has to be done after installation of new shoes or relining the old shoes. If the following conditions are not found, the minor adjustment is usually sufficient;
1. Worn out or out of the round brake drum
2. Brake lining soaked in oil
3. Brake lining worn upto the rivet heads

PROCEDURE :

To perform minor adjustment, on turning the adjustment nut the cam is also turned. This cam is fitted on the brake shoe and the adjusting nut is provided on the back plate. Turning this nut with spanner in the clockwise direction causes the shoes move closer to the brake drum.
To perform major adjustment, remove all brake drums and inspect linings and drums. If the drums are worn out, turn them in case the damage is with in limits or else replace them. In case of linings having reached upto within 1mm of rivet heads, remove the same and reinstall the new ones.

DESCRIPTION :

Clutch assembly is fitted between engine and gearbox. The purpose of the clutch assembly to transmit power of the engine to the rest of the transmission system, by disconnecting & connecting the power is required.

The only adjustment required in a clutch is of the free lever play, which is necessitated on account of wear of the friction lining due to continuous use or with the wear of the throw out bearing carbon ring due to the habit of the driver to press his hand always on the clutch lever. The wear of the friction lining decreases the free lever play. An adjustment nut is provided at the lower end of the clutch lever. To slacken the lock nut first, make the desired adjustment with the adjusting nut and retighten the lock nut.

RESULT :

Thus the adjustment of brake and clutch as per specification is performed.

STUDY OF THREE WHEELER CHASSIS FRAME AND POWER TRANSMISSION SYSTEM.

STUDY OF THREE WHEELER CHASSIS FRAME AND                                                        POWER TRANSMISSION SYSTEM.
AIM :

To study the various features and measure the various dimension of the chassis frame of three wheeler and power transmission system.

TOOLS REQUIRED :

Measuring tape.

PROCEDURE :

Using the measuring tape, note that
Wheelbase:     It is the distance between the centre points of front wheel to the centre point of rear wheel.
Wheel track:  It is the distance between the centre points of two rear wheels.
Over all length: It is the through out distance between front side to the vehicle.
Over all width: It is the distance taken from top portion of the vehicle to the ground level.
Ground clearance: It is the distance taken between nearest part or portion towards ground          level. (ex: differential)

POWER TRANSMISSION SYSTEM :

The system by which the power from engine is transmitted to the wheels is called transmission system. Transmission system carries engine power to the rear wheel. Power at the rear wheels move the vehicle forward overcoming external forces. Clutch is located between the engine and gearbox. Clutch transmits engine power to the gearbox. In Three-wheeler, multiple clutches is used. When the clutch is in the disengaged position, the power transfer is interrupted. Such power interruption will enable shifting of gears smoothly with out damaging gear teeth. Gearbox provides different torque at the rear wheel according to the requirements by engaging different gear combination.

PROPELLER SHAFT DRIVE :

This system is mostly used in three-wheeler. Like four wheelers, the propeller shaft in this system also consists of a sliding joint at one end and universal joints at both the ends.

RESULT :

Thus the various features of the chassis are studied & its dimensions have been measured and the power transmission system also studied.

TRANSMISSION SYSTEM

DISMANTLING AND ASSEMBLING OF THREE WHEELER STEERING SYSTEM.

DISMANTLING AND ASSEMBLING OF THREE WHEELER                                             STEERING SYSTEM.

AIM :

To dismantle, assemble and study of three-wheeler steering system.

TOOLS REQUIRED :

Tool set.

INTRODUCTION :

1. Steering system is used to allow a driver to guide the vehicle along the road and turn it to either direction left or right.
2. Steering arrangement is governed by steering geometry.
3. Steering system consists of front suspension forks, steering stem, steering lock and handle bar.
4. Front suspension forks carry the front wheel assembly. Steering stem is attached to the top of the front suspension forks.
5. Steering stem permits turning of front wheel and hence the vehicle in the desired direction.

PROCEDURE :

1. First remove the pinch bolt.
2. Then remove the crown retaining bolt/ nut.
3. After removing the crown nut, remove the steering stem nut.
4. Remove the bearing.
5. Finally, remove the steering stem.
6. Now all the parts are dismantled and studied.
7. Now reassembling all the parts of reverse order of dismantling.

RESULTS :

Thus the given steering system is dismantled, studied & assembled.

DISMANTLING AND ASSEMBLING OF THREE WHEELER GEAR BOX AND FINDING GEAR RATIOS.

DISMANTLING AND ASSEMBLING OF THREE WHEELER GEAR BOX AND FINDING GEAR RATIOS.

AIM :

To Dismantle and assemble of three wheeler gearbox and find gear ratio.

TOOLS REQUIRED :

Tool set.

OBSERVATION :

Gear box is the integral part of drive line whose function as follows as,
1. To provide different leverage at different driving speed.
2. To provide necessary Torque, which starting the vehicle from rest.

GEARBOX :

1. Power comes from engine to clutch shaft and clutch gear that is always in mesh with a gear on the lay shaft.
2. Helical gears are in mesh always. Helical gears are setting the power with the help of fork, dogteeth and collar. Dogteeth clutch are splined to gear shaft.
3. Gears are provided with integral dogteeth.
4. Collar having internal teeth locks the dogteeth on gear and dogteeth is fixed to the input shaft.
5. Collar is operated by means of fork lever.
6. Lay shaft is a forged component integral with built in gears.
7. Lay shaft is supported in the gearbox housing with the help of bearings.

PROCEDURE :

1. First the main gear assembly is removed.
2. Then the counter gear assembly is removed.
3. Then the lay out assembly is removed.
4. Finally all the gears are removed and count the number of teeth on each gear and found out the gear ratio.
5. Then lay shaft assembly fixed.
6. Now, the counter shaft gear assembly is fixed & bearings are fixed.
7. Finally the main gear assembly is fixed.

STUDY :

Now the number of teeth of each gear counted and using the calculation, the gear ratio is found.

CALCULATION :

Finding gear ratio:

1st gear = PR *(T8/T9)

2nd gear= PR*(T6/T5)

3rd gear= PR*(T4/T3)

4th gear= 1:1

Permanent reduction (PR) = (T2/T1)

T4, T6, T8 à No. of teeth on driven
T3, T5, T7 à No. of teeth on driver

RESULT :

Thus the given three-wheeler gearbox is dismantled, studied and assembled.

DISMANTLING AND ASSEMBLING OF TWO WHEELER GEAR BOX AND FINDING GEAR RATIOS.

DISMANTLING AND ASSEMBLING OF TWO WHEELER GEAR BOX AND FINDING GEAR RATIOS.

AIM :

To Dismantle and assemble of two wheeler gearbox and find gear ratio.

TOOLS REQUIRED :

Tool set.

OBSERVATION :

Gear box is the integral part of drive line whose function as follows as,
1. To provide different leverage at different driving speed.
2. To provide necessary Torque, which starting the vehicle from rest.

GEARBOX :

1. Power comes from engine to clutch shaft and clutch gear, which is always in mesh with a gear on the lay shaft.
2. Helical gears are in mesh always. Helical gears are setting the power with the help of fork, dogteeth and collar. Dogteeth clutch are splined to gear shaft.
3. Gears are provided with integral dogteeth.
4. Collar having internal teeth locks the dogteeth on gear and dogteeth is fixed to the input shaft.
5. Collar is operated by means of fork lever.
6. Lay shaft is a forged component integral with built in gears.
7. Lay shaft is supported in the gearbox housing with the help of bearings.

PROCEDURE :

1.      First the main gear assembly is removed.
2.      Then the counter gear assembly is removed.
3.      Then the lay out assembly is removed.
4.      Finally all the gears are removed and count the number of teeth on each gear and found out the gear ratio.
5.      Then lay shaft assembly fixed.
6.      Now, the counter shaft gear assembly is fixed & bearings are fixed.
7.      Finally the main gear assembly is fixed.

STUDY :

Now the number of teeth of each gear counted and using the calculation, the gear ratio is found.

CALCULATION :

Finding gear ratio:

1st gear = PR *(T8/T9)

2nd gear= PR*(T6/T5)

3rd gear= PR*(T4/T3)

4th gear= 1:1

Permanent reduction (PR) = (T2/T1)

T4, T6, T8 à No. of teeth on driven
T3, T5, T7 à No. of teeth on driver

RESULT :

Thus the given two-wheeler gearbox is dismantled, studied and assembled.

AU2356TWO AND THREE WHEELER LAB

1. Road performance test of a two-wheeler using chassis dynamometer.

1. Performance test of a shock absorber.

1. Performance test on coil spring.

1. Two-wheeler chain tension test.

1. Brake and clutch adjustment as per specification.

1. Dismantling and assembling of two-wheeler gear box and finding gear ratio.

1. Dismantling and assembling of three-wheeler gear box and finding gear ratio.

1. Three-wheeler brake and clutch play adjustment.

1. Dismantling and assembling of three-wheeler steering system.

1. Study of three-wheeler chassis frame and power transmission system

CHARACTERISTICS CURVES OF TRIANGULAR NOTCH

CHARACTERISTICS CURVES OF TRIANGULAR NOTCH

AIM:

To determine the co-efficient of discharge of flow through triangular notch.

APPARATUS REQUIRED:

1.      Notch tank
2.      Triangular notch
3.      Hook gauge
4.      Collecting tank
5.      Stop watch
6.      Piezo meter
7.      Meter scale

FORMULAE:

1. ACTUAL DISCHARGE:

Qact = A x h / t               (m³ / sec)

Where,
A = Area of the collecting tank                       (m²)
h  =  Rise of water level in collecting tank       (cm)
t = Time taken for ‘h’ rise of oil in collecting tank (s)

2. THEORETICAL DISCHARGE:

Qthe   =  (8 / 15) x (tan θ / 2) √ 2 x g x H 5/2        (m 3 / s)

Where
H = Manometer height in m
g  = Gravity in   m / s

3. CO-EFFICIENT OF DISCHARGE:

Cd = Qact  / Q the                                (no unit)

DESCRIPTION:

1.      The inlet valve is opened and water is allowed to rise up to the level of the triangular notch
2.      The pointer of the manometer gauge is adjusted so that it coincides the water surface and note down reading
3.      The inlet valve is opened so that the water flows over the notch at the same rate
4.      The water level is noted by means of point gauge
5.      The readings for H2 is noted
6.      The time required for10 cm rise of water level is noted
7.      The above procedure is repeated for different discharge

RESULT:
The co-efficient of discharge of triangular notch is Cd = ……(no unit)

Co efficient of discharge Cd  (no unit)

Theoretical discharge
Qthe x10-3
m3 \ sec

Mean =

Actual discharge Qact x10-3
m3\sec

Time taken for 10 cm of rise of water t sec

H= H1~ H2 cm

H2
cm

H1
cm