What are the causes of vehicle deviation and steering wheel deviation?

What's the maximum distance your truck can travel in a year? For the old drivers who are often on the road, it is easy to 200,000-300,000 kilometers a year, and many card friends also joke that they are people who live on wheels. The car is the same as people, run more, older there will be a variety of problems, such as tires need to be replaced, the saddle, the wheel end need to butter and so on operation, are normal phenomena.

However, recently there are card friends in the background to feedback to us, trailer axle the vehicle after a certain number of years, began to run off, the steering wheel is not correct, it is understood that there are many card friends. For oil changes, machine filters, air filters and other routine maintenance projects, our card friends are generally familiar with the heart, but the steering wheel is not correct, vehicle deviation of many card friends are still the first time to encounter, very affect our daily car experience.

If the steering wheel is not correct at present, the vehicle can move forward normally when it stabilizes the direction, and the steering wheel will not be corrected from time to time, then it is likely to be an assembly and adjustment problem. Then at this time you need to go to the service station, check the connection rod between the steering wheel and the direction machine, commonly known as the steering column, whether there is a connection dislocation problem, if only this problem, then the maintenance method is also very simple, remove the steering wheel and re-aim to insert.

The steering wheel may also have a second reason, steering rod deformation, ball head bushing ore, because the vehicle in the factory, the original engineer designed the four-wheel positioning value, if the steering rod, ball head bushing and a series of parts in normal operation, the vehicle almost will not appear tire wear, run off the situation (does not rule out vehicle design problems), With it, the steering wheel is not in the zero position, and the driving is unstable.

The steering wheel may also have a third reason, that is, the direction machine fastening bolts are loose, this situation often does not appear on the new car, but will appear in the truck with a running time of 3 months, the direction machine according to the vehicle calibration has a service life, including its parts and a longer time, but if the card friend vehicle carries too much and too heavy goods, It will make the vehicle steering machine in overload operation for a long time, and its fastening bolts loose is completely understandable.

The steering wheel is not correct in fact, the impact on daily driving is relatively large, especially for some driving tractor card friends, in reverse and unloading, because the steering wheel is not in the zero position, resulting in the reverse direction is easy to misjudge, card friends originally thought that the vehicle has been straightening after the back pour, but due to the steering wheel and steering wheel pointing poor deviation, It is easy to cause friction and safety accidents, so when the steering wheel is not correct and is not at the zero position, it is necessary to contact the service station at the first time to solve this problem.

In addition to the above situation caused by the internal reasons of the steering wheel is not correct, the left and right side tire tire pressure is inconsistent, tire wear difference may also lead to the vehicle when the steering wheel is not at the zero position, but this situation will generally be accompanied by the phenomenon of deviation. Although the problem of the wrong steering wheel is solved, there are card friends that the car still has a deviation, and the direction needs to be corrected repeatedly when driving in a straight line, so what is this?

It is understood from the explanation of the maintenance engineer that the trailer axle direction of the vehicle deviation means that the direction will automatically deflect with the speed during the driving process, if the steering wheel of our card friend is not at the zero position, but the direction of the vehicle will not deviate during the driving process, then the high probability is only the problem of the steering system assembly, which will not involve other parts. However, if on this basis, the direction of travel of the vehicle will automatically be deflected, it can be determined that the deviation + steering wheel is not correct.

Overall, the deviation phenomenon includes the situation that the steering wheel is not at the zero position, but the deviation is not only a problem with the steering system, but the chassis mechanism, walking mechanism and other links. First of all, let's take a look at the chassis system, which contains many factors such as the vertical shaft backward tilt is too small, the driving direction, the body attitude, the front wheel front bundle, and the return Angle of the steering machine.

From a split point of view, the vertical shaft is too small, also known as the kingpin rear inclination is too small, it belongs to the truck front bundle system, the kingpin is our steering knuckle around the steering bridge (shaft) rotation axis, also known as the steering shaft. And its rear inclination Angle is too small will lead to the vehicle driving instability, the direction of the deviation of the situation, if the joke, we put the bicycle hand and the front axle of the line and the ground Angle imagined as 90°, such a bicycle riding fast will be stable?

It sounds metaphysical, and how does that change in this case? In fact, it is very simple, by increasing the kingpin tilt Angle can solve this problem, for the truck the most direct way is to join the skew iron, that is, we often say the gasket, through different angles, sizes of skew iron with four wheel positioning can solve this problem, and its price is not expensive, just disassembly and higher labor costs.

Then, the driving direction is only whether the driving force on both sides of the vehicle is balanced and stable, with the four-bridge distance of 8X4, if the force distribution on both sides of the drive shaft is uneven, the bearing is burned on one side, and the driving force is reduced, then it may lead to the uneven distribution of the driving force on both sides.

Then in the chassis system, there is another key point is the size of the front wheel front bundle, the front wheel front bundle refers to the difference in the distance between the front end face and the back end face of the front wheel in the transverse direction of the car, and can also refer to the Angle between the direction of the body and the front wheel plane. If it is simply understood, it is that all cars have a certain front Angle, from the top down to see whether the tire is eight or eight, and this will also affect whether the vehicle can be stable and straight.

Different models of each brand have different values of the front bundle. After the truck turns back to the right direction, it can automatically return to the straight line driving position. This parameter is determined by the positioning parameters of the steering wheel, and the front bundle is one of them. Whether the car runs off course makes a big difference.

Of course, in addition to the above reasons, there are other factors that can cause the vehicle to run off, such as the body attitude, if in the cargo compartment of the heavy truck, all the light goods are loaded on the right side, and all the heavy goods are loaded on the left side, then the vehicle is reasonable, and in this case if you encounter a strong cross wind or downhill right turn, then the vehicle will even have the risk of rollover.

In the direction machine, the return Angle deviation of the direction machine itself will also affect whether there is a deviation of the vehicle, and the direction machine return Angle deviation card can be determined by itself, in place around the direction of 90-180°, feel the weight of the steering wheel is the same uniform, if the rotation to one side has significantly greater resistance, Then it can be determined that there is a certain problem with the direction machine itself.

At the same time, the tire pattern will also indirectly affect whether the vehicle runs off, for example, the tire model on both sides is inconsistent, the tire pattern on both sides is inconsistent, the tire pressure on both sides is inconsistent, and the tire wear on both sides is inconsistent, which may cause deviation under different road conditions, which is more common in the field of medium and heavy trucks.

It is not taboo to say that the vehicle deviation itself is a relatively huge problem, which is not only related to the steering system, but also has a relatively close relationship with the chassis, the walking system and even the tires and the trailer axle. At the same time, it is understood that some models may have problems in calibration when they leave the factory.