From small cars to big trucks, every vehicle operates on the simplest mechanism: its wheel.
Recently cars have been modified into different bodies, designs, and sizes; some auto parts are now considered old. Some auto parts are obsolete or have been modified into a newer version.
The wheel is a circular part that is meant to turn on the axle bearing. With axles, wheels allow very heavy things to be transported, lowered, or managed for movement. They carry loads or perform labor in machines.
These wheels create rotary motion and are responsible for transporting you and your car from one location to another. Without wheels and tires, cars and trucks would be simply, expensive lawn ornaments.
There are multiple parts of a wheel, and each has a particular job, but not every drive knows what they all are. To give you a brief rundown of these parts, we will examine the basic parts of a wheel and tire, below.
So, let’s begin.
Parts of Car Wheel
The following are the main parts of car wheel:
- Wheel bearing
- Wheel rims
- Tire
- Wheel hub
- Wheel fasteners
- Barrel
- Bolt circle
- Outer lip
- Flanges
- Centre bore
- Valve system
- Spoke
- Center cap
- Beads
- Lug hole
#1. Wheel Bearings.
Antifriction bearings are often used as wheel bearings. Antifriction bearings provide low-friction between the turning wheels to the stationary parts of the vehicle.
Antifriction bearings have three basic parts. These parts are in order, the inner race, rolling element, and outer race.
The overall purpose for wheel bearings is to allow wheels to spin free (as free as possible) with little or no friction.
Car wheels have hubs in the center of the wheel. The wheel bearings fit in the hub and ride on a metal axle shaft that helps reduce friction as the wheels rotate.
Wheel bearings must be carefully matched to the vehicle application, load type and maximum bearing speed of the intended use.
#2. Wheel Rims.
Rims are part of car wheels holding the tire to the wheel. They support and seal the tire to the wheel, ensuring proper fitting of the tire to the rim.
Typically, the rim is made of steel and mounted on the rim, which is bolted to the hub. Steel rims are much lighter and decrease unsprung weight.
Modern cars use increasing amounts of rims made from materials like aluminum, aluminum-magnesium alloy, and graphite, called custom rims.
Custom rims allow room for customization and provide colorful and unique styling to a car’s wheels at an added cost.
#3. Tire.
Everyone knows that tires are meant to support the weight of the vehicle, absorb impact and shock from the road, transmit traction, torque, and braking forces from the vehicle to the road surface, and maintain directional travel. Tires are flexible rubber with a covered outer surface and filled with compressed air.
Although tires are part of the suspension system, they act as covers so that the wheel rims do not wear out from rubbing or touching the ground. Tires have many different parts, but the most important part is the threads that touch the road, wear out, and are replaced.
Stud and treated tires generally have grooved, notched, and other types of patterns to maximize friction and assist in channeling water and debris away from the wheel.
#4. Wheel Hub.
The wheel hub assembly attaches the car wheels to the vehicle and permits the wheels to free-wheeling which enables the driver to drive safely. The wheel hub assembly is also an important part of the anti-lock braking system (ABS) and traction control systems (TCS).
It frames the center of the wheel, to which the rim is attached, and includes brake pads, calipers, and rotors. It holds tires in place with five bolts and a lug nut from the center.
#5. Wheel Fasteners.
In wheel and tire design, an important factor is how the rim mounts to the hub or axle flange.
Every vehicle utilizes wheel studs as wheel fasteners used at the hub or axle flange. These are likely threaded bolts or studs pressed into (or bolted to) the hub or flange to form a tight joint.
Usually, the head of the stud will be larger than the stud hole in the hub or flange. The axle center is raised above the hub or flange unit so the center locates with the center of the rim.
#6. Barrel.
The parts of the wheel between the outboard face and inboard rim edge is called the barrel.
The barrel’s function is to create a surface for mounting the tire. The inner diameter of the barrel is called a drop center and is a key factor in determining mount wheel type.
For front-wheel drive vehicles, the drop center is near the front of the wheel. Whereas, for rear-wheel drive vehicles, the drop centers are located near the rear of the wheel.
The sides of the barrel are formed into flanges to prevent the tires from slipping when the car is in motion.
#7. Bolt Circle.
The bolt pattern for a wheel is also called bolt circle or bolt circle diameter. This is designed by the lug bolt area. The bolt circle is expressed by the number of lugs by the diameter of the imaginary circle formed around the centers of the lugs.
For example, if the wheel has 5 lug bolt holes and a BCD of 4, it would be written as 5×4″. Bolt circles modulate generally between Nissan or Mercedes, and it makes it difficult to cross-fit wheels design for different car manufacturing.
#8. Outer Lips.
The outer lip is the most likely part (the area that can be repaired) to collapse when a wheel impacts the pothole. Technically, the lip can be bigger or deeper – until it meets the face of the wheel.
A deeper outer lip is more at risk of damage by Impacts because the spokes do not provide much support. The outer lip is measured from the face of the wheel to the edge, making it on the outside.
#9. Flanges.
Usually, a wheel flange is a connector that attaches the vehicle’s wheels to the axle. The wheel flange is mechanically locked to either the drive axle or to the end of the spindle. Additionally, it is one of the structural components on the sides of the wheel to minimize tire slip.
Flanges with lug nuts have been the standard mounting method for car wheels for a long time. The flanges are on both ends of the wheel and keep the tire snugly held onto the wheel in even extreme conditions or road surfaces.
#10. Center Bore.
The center of the wheel features a machined opening to correctly center the wheel on the vehicle.
A wheel needs to be hub-centric to limit the potential for vibration. This is usually an empty space that holds the functional area that fits over the axle and supports the car’s weight.
If the hub collar diameter is greater than the central bore diameter, the new wheels will not fit onto the hub collar. If the center bore is greater than the diameter of the hub, then the wheel can be fitted onto the collar, but it would be very difficult to achieve the desired fit.
#11. Valve System.
Tires typically inflate and deflate through a valve system. The valve keeps air or nitrogen inside the tire so it doesn’t escape. It is a crucial part of maintaining tire pressure and safety.
Wheels usually have two valve stems for two purposes. One valve stem pumps the air in and one refills the nitrogen air. Simply put, one valve stem fills with nitrogen air while the other valve stem fills the tire with regular air.
#12. Spokes.
Spokes are essential connections between the rim of the wheel and the plate in the wheel’s center; this is also where the lug and bolt holes hold the wheel to the car, and they protect the outer edge by absorbing punishment from common minor impacts.
Spokes come in all types of designs. Five simply spokes are classic, but even more intricate is a design with as few as three spokes. Spoke stability or strength will depend on design and material.
#13. Center Cap.
A high-quality car wheel center cap protects the wheel rims and tires of the vehicle from dirt and the detrimental effects of sunlight. For those who park their vehicles in public places, car wheel caps are a worthy investment.
The center cap is located in the center of the wheel where the spokes meet. On some wheel models, the center cap can be removed. In fact, most wheel rims do not have a removable center cap, and the wheel does not need a center cap to function properly.
The center cap (given the variety of styles and designs) simply has a more uniform and finished appearance over a center cap-less wheel.
#14. Beads.
The primary purpose of tire beads is to anchor the tire to the outer surface of the wheel. They use the tension of the wires to pack the rubber tightly into the wheel’s frame. Beads are also part of the wheel that will transfer energy.
If the beads are damaged the energy may transfer awkwardly and the whole vehicle shake from that energy, especially at high speeds. Beads are important because they create an airtight fit against the wheel side, and they allow for a more efficient transfer of forces occurs as the car is moving.
#15. Lug Hole and Nut.
The lug hole is typically cut to create a bolt circle on the centered disc. These are the holes into which the lug nut is bolted. Lug holes are typically empty holes covered by a center cap. The lug holes form a bolt circle with a diameter called the bolt circle diameter.
The lug nut goes into the lug hole to fasten the wheel hub to the threaded wheel stud of the vehicle’s axle, proper centering of the wheel on the axle, and securing the wheel. It is a nut fastener with a round or conical (tapered) end.
Conclusion
As stated, the wheels are the car parts that have always put into service. The wheels are loaded with circular shapes that cause rotary motion and primarily roll the automobile, in other words, move the carriage from point A to B, therefore wheels are without a doubt a vital part of any automobile.