AUTOMOBILE ENGINEERING
AUTOMOBILE ENGINEERING
Team members
S. Ganesh (09M108)M. Suryanarayanan (09M145)S. Raghu Nandan (09M128)M. Navaneetha Saravanan (09M119)K. Thillai Vadivazhagan (09M147)R. Kamal Raj (09M111)Sharath Kumar (08M153)
WHEEL BALANCING
WHY DO WE NEED WHEEL BALANCING?
An unbalanced wheel produces more vibration.
It is transmitted to body through the suspension components.
It can also resulting in a wobbling of the steering wheel or of the entire vehicle.
The ride disturbance, due to unbalance, usually increases with speed.
SYMPTOMS OF A WHEEL THAT IS OUT OF BALANCE
Vibration in the steering wheel at certain high speed.
Vibration in the seat or floorboard.
Scalloped or cupped wear pattern on the tires.
FACTORS AFFECTING THE WHEEL BALANCE
Lateral run out of the wheel.
Radial run out of the wheel
Uneven distribution of the weight around the axis of rotation.
Consequences of Wheel Imbalance Accelerated and uneven tyre wear.
Undue stressing of car’s suspension.
Damage to steering components.
Driver fatigue.
Impaired tyre traction and steering control.
Increased fuel consumption
General Process of Wheel Balancing
The mechanic removes the wheels and places them on a machine which spins them and measures the amount and location of the imbalance.
A small weight will then be attached to the rim of the wheel to even out the weight distribution and bring the wheel back into balance.
Metals such as zinc or steel -wheel balancing weights.
Smoother, less tiring ride, a safer car, lower fuel bills and tyres that last longer.
WHEEL BALANCING
Balancing of weight of the entire wheel assembly.
Placing a lead weight on the side of the wheel opposite to the heavier spot.
TYPES OF BALANCING
Static balance
Dynamic balance
STATIC BALANCING
A freely rotating wheel assembly is mounted on a shaft.
When the weight of the wheel and tyre is uniformly distributed about the
axis of the wheel then it is said to be statically balanced.
PROCEDURE FOR PERFORMING STATIC BALANCE
This is done by using the electronic balancer.
The front wheels are lifted on hydraulic jack and
made sure than the wheels can turn freely.
The balancer equipment is positioned having its
pulley in contact with the tyre tread.
PROCEDURE FOR PERFORMING STATIC BALANCE
The balancer is moved into position to point the strobe light at the wheel.
The pick-up magnet is positioned in contact with a clean flat surface on
the front suspension as close as to the wheel.
If the pick-up magnet is in proper contact, the strobe light will flash when
the top of the tyre is tapped, indicating proper balance of the wheel.
DYNAMIC BALANCING
It describes the forces generated by asymmetric mass distribution when the
wheel is rotated.
To avoid this, the unbalanced weight should also be balanced in dynamic
condition or while running or rotating.
PROCEDURE FOR PERFORMING DYNAMIC BALANCE
The wheels are turned out approximately one half of their
steering angle.
The pick-up magnet is positioned in contact with the external
front and end of the brake housing flange at the wheel rotation
axis.
The wheel is correctly spanned and the highest meter reading is
recorded, the static balance procedure is followed.
PROCEDURE FOR PERFORMING DYNAMIC BALANCE
The dynamic balance of the wheel is checked as per the static balance.
If still out of balance, the wheel is stopped and the reference mark is
brought in position or time recorded.
The inspection is repeated as previously directed.
If the wheel is still out of balancing, the balance procedure will proceed till
the meter needle remains in the green area.
WHEEL BALANCER – SBM700
Functions
Quick and accurate measurement of imbalance value.
Automatic inspection of dynamic and static balance.
Compensation of static and dynamic balance.
Features
Manual measuring scale (manual input of values)
Static and dynamic balance inspection both with compensation
Indication of imbalance both in grams and ounces
Precision of imbalance up to 1 gram
Automatic correction and memorization of structural parameters
Specifications
Rim Diameter:254-558mm Rim Width:38-457mm Balancing precision:1g Cycle time:7s Power supply:220V/110V 50Hz/60Hz Motor Power:180W/370W RPM:240rpm Working noise:<70dB Max. Wheel Weight: 65kg Dimensions: 1200*1000*1350mm
CONTROL PANEL
Control Panel
OPERATION FROM MEASUREMENT SCREEN
1 Push buttons, presetting of correcting mode
2 Push-button, displaying of residual unbalance
PRESETTING OF DIMENSIONS
Automatic measuring
The wheel diameter and width must be manually preset. The automatic
measurement of the diameter is provided as OPTION.
The balancing machine is equipped with gauge for the automatic measuring
of the distance.
MANUAL PRESETTING
If necessary, the dimensions can be entered or modified manually
on the presetting of dimension screen. According to the following
procedure,
DIAMETER - Press push-button [d]
- Preset nominal diameter “d”
WIDTH - Preset push-button [b]
- Preset the nominal width stamped on the rim “b”
MEASUREMENT OF UNBALANCE
The results and arrows for positioning the balancing weight in
the application point are displayed in this screen.
After positioning, apply the weight in the top twelve o’clock
position.
SAFETY PRECAUTIONS
Before starting to use the balancing machine, carefully read the operating instruction
manual.
Keep the manual in a safe place for future reference
Refrain from removing or modifying machine parts, which would impair correct operation.
Do not use strong jets of compressed air for cleaning
Use alcohol to clean plastic panels or shelves (AVOID LIQUIDS CONTAINING SOLVENTS)
SAFETY PRECAUTIONS
Before starting the wheel balancing cycle, make sure that the wheel is securely
locked on the adapter.
The machine operator should not wear clothes with flapping edges. Make sure that
unauthorized personnel do not approach the machine during the work cycle
Avoid placing counterweights or other bodies in the base, which could impair the
correct operation of the balancer machine.
The balancing machine should not be used for purposes other than those described
in the instruction manual.
ERRORS
No signal of rotation. Could be caused by a faulty position transducer or by
the motor not starting or by something preventing the wheel from turning.
During the measurement spins, wheel speed drops to 60 rpm. Repeat the
spin.
Errors in mathematical calculations – improper calibration.
Wheel turning in opposite direction.
REFERENCES
Automobile Engineering by Kirpal Singh.
Automobile Engineering by Gupta.
www.garageindia.com
www.wikipedia.com