What is Wheel?
It is well known that how important, are the wheels in automobiles.
The vehicle can be pulled even with no engine. However, without the wheels the vehicle cannot be moved at all. Furthermore, the wheels carry the full load of the vehicle and give smooth ride. Besides that the wheels help in operating the vehicle in control with the help of the steering.
Requirements of the wheel
1. Wheel must bear the full load acting on the vehicle.
2. It must make the vehicle weight easy to move and steer easy.
3. It must help to move the vehicle
without the engine.
4. It must withstand vibrations of the
5. It must withstand the braking force
when the brake is applied.
Properties of the wheel
1. It must be able to withstand the full
load of the vehicle.
2. The wheels must be at equal in position while driving the vehicle and at rest as well.
3. The weight of the wheels should be less.
4. The wheels must be easy to remove from the axle and fix in the axle.
5. The wheels must be easy to control by steering mechanism.
Types of wheels
Generally there are three types of wheel. They are
1. Disc wheel
2. Wired wheel
3. Cast wheel
This type of wheel is commonly
used in all automobiles.Because its structure is very simple and the construction is very strong and cost effective.The disc wheel is made of two parts. They are
The top part of the rim has the provision for fixing the tyre correctly. The disc is connected with the rim by welding. Depending on the size of the wheel and the disc the disc can be made as an integral part of the rim or separate ones. The part of the tyre which is used for place it on the rim is
called as the tyre bead. The tyre cannot be removed or fitted if there is no pit in the rim. The tyre fitting area in the rim is generally in tilting angle between 5° and 15°. Therefore, when air is filled in the tyre, the bead makes a tight fit with the rim. In tubeless tyres this tilt structure acts as a tight seal. The disc in the disc wheel does the work of the spoke. The wheel is fitted on the axle by the bolts. There are holes provided on the wheel disc as shown in the picture.Through these holes air is allowed to enter inside the brake drum and the air cools
the brake drum. There is a cap provided for the wheel disc and a hole is made on the rim for placing the tube valve.
1. The construction of the disc wheel is simple, durable and cheap.
2. Its maintenance is low.
3. It is suitable for all light and heavy
4. No curves or bends occur on the
Unlike the disc wheel, the hub is
located at the center of the wheel and the rim is at the top separately. The rim and the hub are connected by the wires called as spokes. . We can find
this type of wheels used in two wheelers such as bicycles and motor cycles. The spokes in the two wheels withstand the vehicle weight, pulling force and braking force. For withstanding these forces the
spokes are connected between the wheel hub and the rim. There are splines made in the hub for fixing it on the hub axle.The weight of wired wheel is comparatively lower than the disc wheel and has high cooling efficiency and hence it is used
in racing cars.
Advantages of wired wheel
1. It is lower in weight and has more
durability than a disc wheel.
2. It allows the brake drum to cool very quickly and easily.
3. It can be fixed and dismantled easily whenever necessary.
1. Maintenance cost is high.
2. There are possibilities for bends to
occur in the wheel.
3. Tubeless tyres cannot be used because of the holes present in the rim for the spoke wires
The modern automotive wheels
are generally made up of aluminum or magnesium alloy materials. Cast wheels are mostly used in cars. The simple structure of this wheel can be seen in figure. Forged wheels are
mostly used in heavy vehicles. These
types of wheels are less in weight. The
wheels made of magnesium alloy are
50% less than the weight of the steel
wheel, and the aluminum alloy wheels are 70% less than the weight of the steel wheel. Even though the weight is lower than that of steel wheels these wheels have the strength which is equal to the
steel wheels. These metal alloys have the ability to transfer heat and reduce the heat generated in the tyres or brakes. Moreover these materials are used for manufacture the wide rims. This gives more vehicle stability. Magnesium alloy material has
the ability to withstand heavy loads. It
could also withstand more vibrations and shocks occurred in vehicles.