A wheel is a structure that includes a rim, a connecting element (disc) and fastening parts. A pneumatic tyre is mounted on the wheel, after which it is attached to the hub.
The wheels provide contact with the road surface, participate in creating and changing the direction of travel, and transfer the load from the car’s mass to the road.
The following requirements are imposed on the wheels:
- reliable fastening to the hub;
- strength and durability;
- ease of mounting and dismounting of the tyre;
- minimal runout and imbalance;
- full compliance with the used tyre in terms of dimensions, rigidity and rim design.
Depending on the primary purpose, the wheels are divided into driving, steerable, combined, supporting. The drive wheels convert the torque from the transmission into traction, which creates a forward motion in the vehicle.
The steered wheels receive the pushing force from the vehicle body from the suspension and use the steering to set travel direction. The combined wheels act as driving and steer wheels at the same time. The support wheels provide rolling support to the rear of the vehicle body or frame, converting push force into rolling.
Depending on the rim’s design and its connections, all wheels are divided into disc and disc-less. Disc wheels are installed on all cars and most trucks; disc-less wheels are used only on heavy vehicles and buses.
On vehicles with increased cross-country ability, disc wheels with a split rim are used. The wheel structure of cars and trucks with a carrying capacity of up to 1.5 tons is made in a one-piece form. It is welded from two parts of the rim and disc. The disc is a continuous, notched and ribbed design. The cutouts are necessary to cool the brake and to reduce the weight of the disc.
The wheel rim includes:
- the rims, which are the side stops for the beads of the tyre, the distance between the rims is the width of the rim;
- shelves, which represent the seats of the tyre beads;
- grooves to facilitate tyre mounting.
The wheels of tubeless tyres should be stiffer and more sealed. Tubeless radial tyres use safety circuits to prevent rapid air release. However, these contours make tyre mounting a little tricky.
On trucks and buses, disc and disc-less wheels with a collapsible rim are used. The wheel disk must perceive vertical, lateral, and longitudinal forces from the road and transfer them to the wheel hub.
Wheel balancing is the process of eliminating imbalance imbalances in the wheels. There are three types of balancing:
- static balancing implies a decrease in the primary vector of imbalance of the wheel when the axle of the wheel and its main central axis of inertia are parallel;
- dynamic balancing implies a reduction in wheel imbalances, correcting its dynamic imbalance, in the case when the wheel axis and its main central axis of inertia do not intersect in the center of gravity or intersect;
- instant balancing implies a decrease in the central moment of unbalances when the wheel axis and its main central axis of inertia intersect in the wheel centre of gravity.
An imbalance in the wheel leads to runout. As a result of beating and imbalance:
- the ride comfort is reduced;
- the vibration of the car body increases;
- the service life of shock absorbers, tyres and steering is significantly reduced;
- fuel consumption increases;
- the cost of car maintenance increases.
A car tyre includes:
- a frame;
- chambers and sealing layer;
- rim tape;
The following requirements are imposed on car tyres :
- tube and tubeless tyres mounted on the rim must be sealed and also ensure the stability of internal pressure;
- compliance of elastic properties with vehicle parameters and driving conditions;
- guaranteeing the lowest specific load in contact with the road;
- the adhesion of the tyres to the road surface must be sufficient, and the rolling resistance must be minimal;
- tyre runout should not exceed permissible values;
- the type of tread pattern must correspond to the kind of road surface;
- the tyre must have sufficient strength, wear resistance of the tread and must provide the specified durability;
- the noise level when driving must be within the permissible value;
- device for assembly, disassembly and maintainability.
Depending on the purpose, car tyres are: for cars, trucks, off-road vehicles. According to the method of sealing, tyres are divided into tubed and tubeless. If you want a good recommendation for tyres with novel tread compounds that add to high mileage capacity and require minimal maintenance, we suggest Falken Linam Van01.
After a while of driving a car, tyres do not wear out; equally, rear tyres wear faster than front tyres, and right tyres wear out more quickly than left ones. For the tyre wear to be more even, they must be rearranged after a 500 km run. Tyres that have holes or any other mechanical damage must be returned for repair.