Suspension is a general term for all force-transmitting connection devices between the semi-trailer frame and the axle, which is used to transmit the force and torque acting between the wheels and the frame, and the buffer is transmitted from the road to the frame. Or the impact force of the body, and reduce the vibration caused thereby to ensure that the car can run smoothly.
Suspension is an important part connecting the chassis and the frame. The supporting force, braking force, driving force, etc. of the vehicle are all transmitted through the suspension system, and it can also reduce the impact force of the bad road on the vehicle and ensure the stability of the vehicle. , its importance is self-evident. Suspensions are generally divided into independent and non-independent suspensions. For semi-trailers, due to the need for strong bearing capacity, non-independent suspensions are used, and there are four common suspensions for semi-trailers.
1. Rigid suspension
Rigid suspension is that the left and right wheels are connected by an axle. The chassis of the rigid suspension directly acts on the axle between the wheels without spring as a buffer. When the road is uneven, it completely relies on the swing of the balance beam to maintain the relative relationship between the front and rear axles. balance.
This kind of suspension is relatively rare at present, because its shock absorption effect is very poor, and it is mainly used on low-flat semi-trailers that carry goods at low speeds.
2. Steel plate suspension
The leaf suspension is also known as the tandem leaf spring balance suspension, which is also the common leaf spring suspension. It is mainly composed of leaf springs, suspension supports, connecting rods, U-bolts, etc. The longitudinal force of the body is directly on one axle.
The biggest advantage of this kind of trailer suspension is low cost, reliable work and easy maintenance. Because of this, the steel plate suspension is currently used in the largest proportion of domestic semi-trailers, about 70-80%.
3. Single-point suspension
That is, the common front and rear brackets of the leaf spring are reduced to a single bracket and connected to the car body, which can equally divide the force points to different axles. Compared with the ordinary leaf spring suspension, the single-point suspension has a larger bearing capacity, and the single-point suspension is generally used on heavy-duty trailers.
4. Air suspension
Air suspension is also called airbag suspension. Its most notable feature is the airbag-type air spring. The air spring itself is relatively light, the air medium in the airbag has less friction, and there is almost no noise during operation, and its life is the life of the leaf spring. 2-3 times. However, when the air spring is used, a rod system that can transmit various forces and moments other than the vertical force must be set up, so the suspension structure is complicated; in addition, the air spring has strict requirements on sealing, and its cost is also high. Compared with other suspensions, the air suspension has better cushioning force, which can effectively protect the goods and improve the driving comfort. At present, the air suspension is mainly used in the transportation of precision instruments and hazardous chemicals.
According to the technical conditions for the safety of motor vehicle operation, the three-axle fence type and warehouse grid semi-trailer must be installed with disc brakes and air suspension before they can be licensed and driven on the road. So what's so good about air suspension?
Advantages of air suspension
1. Good shock absorption effect. Compared with the traditional leaf spring, the air bag is obviously softer and more comfortable. It forms a soft connection between the frame and the axle, and the bumps and shocks from the road can be greatly alleviated, in addition to enhancing the driving. Comfort is also a kind of protection for cargo.
2. Reduce the load stress. The compressibility of the air enables the airbag suspension to easily cope with road bumps while reducing load stress, prolonging the service life of axles and semi-trailers, and reducing vehicle costs to a certain extent.
3. Its own weight is smaller. Lightweight is a development trend in the current trailer accessories industry. Compared with traditional suspension, air suspension is lighter in weight. For standard load users, more free weight space can be obtained, and no-load users can save fuel and energy. Synergistic.
4. Long service life. The weight of the air spring itself is relatively light, and the friction of the air medium in the air bag is relatively small, and the service life can reach 2-3 times that of the leaf spring, helping the owner to save costs better.
Air suspension has many advantages, but there are also some disadvantages objectively
1. Compared with other suspensions, the structure of air suspension is more complicated, because to use air springs, it is necessary to set up rods that can transmit various forces and moments other than vertical forces, which also leads to a certain degree of Its price is higher.
2. Corresponding to the high price is the maintenance cost. In addition, compared with the traditional leaf spring, the airbag is more easily damaged in material, and the maintenance cost should not be underestimated.
3. Once the air suspension fails, it cannot continue to drive, and can only call for towing service. Unlike traditional suspensions, even if there is an oil leak, you can insist on going to the repair outlet.
4. The air suspension has good cushioning, but under full load, there will be nodding or trailing when braking or starting, and skilled driving skills are also required.
Although the advantages and disadvantages of air suspension coexist, the advantages are more obvious under comprehensive consideration, otherwise the air suspension will not become an officially designated must-have suspension. In addition, with the popularity of "lightweight" in the commercial vehicle industry, shippers are paying more and more attention to cargo damage, and the competition among peers is becoming more and more fierce. This industry background also promotes the use of air suspension to a certain extent.
It is recommended that car owners try to choose a reliable brand when purchasing air suspension, which can also reduce the cost of subsequent maintenance and replacement to a certain extent. The air suspension produced by Vehicle Master is composed of air spring, shock absorber, height control valve, guide arm, follow-up steering mechanism, etc. It adopts 3D molding technology and has stronger bearing capacity. Special seals can fully ensure the suspension during operation. temperature, extended service life, more flexible parts assembly design, shorter installation time, and maintenance based on actual conditions, reducing maintenance costs. Vehicle Master can be customized according to customer needs to meet the needs of different users to the greatest extent. Products are exported to Europe, America, Southeast Asia, Africa and the Middle East.