How many kinds of trailer suspension? How to solve the most common faults of air suspension?

Under normal circumstances, the suspension of the semi-trailer can be mainly divided into four types:

1, rigid suspension.

The chassis of the rigid suspension directly acts on the axles between the wheels, without a spring as a buffer, and completely relies on the swing of the balance beam to maintain the relative balance of the front and rear axles when the road is uneven.

This kind of suspension is relatively rare at present, because its shock absorption effect is very poor, mainly used in low-speed cargo carrying low-plate semi-trailer.

2. Steel plate suspension.

Also known as tandem steel leaf spring balance suspension, that is, a common leaf spring suspension, mainly composed of leaf springs, suspension supports, connecting rods, U-bolts and so on.

The biggest advantage of this trailer suspension is low cost, reliable work and easy maintenance. Because of this, the steel plate suspension is currently the largest proportion of semi-trailer applications in the country, about 70-80%.

3. Single point suspension.

That is, the common leaf spring before and after the bracket is reduced into a single bracket connected to the body, which can be divided into different axles, so the bearing capacity is larger, and is generally used in heavy trailers.

4. Air trailer suspension.

Also known as the air bag suspension, its most significant feature is the air bag type air spring, compared with other suspension, the buffer force of the air suspension is better, can effectively protect the cargo, improve driving comfort, is currently mainly used in the transportation of precision instruments, dangerous chemicals and the like.

The most common failure of air suspension is that the air bag is wrinkled or the air bag is less or no air, which leads to different reasons for these two situations, and the treatment method is not the same.

1. Air bag folds.

The reason:

(1) When the vehicle is transferred and hoisted, the air bag is stretched out more and is not restored normally, resulting in the air bag wrinkling;

(2) When the vehicle enters and leaves the maintenance workshop or a large slope platform, it may also cause individual airbags to be overstretched, resulting in airbag wrinkles.

Treatment method:

Open the rubber connector under the horizontal height valve, lift the rod up, wait for all the air bags to be full, and then install the rod back, the air bag can return to normal.

In addition, if such a failure often occurs during driving, it is necessary to consider adding a limiting device between the axle and the frame.

2. Less or no air in the air bag.

The reason:

(1) Air suspension special air storage cylinder no air or low pressure, when the trailer air pressure is less than 6 kg, the pressure protection valve will suspend the air supply to the air suspension air storage cylinder to ensure that the brake system maintains sufficient pressure;

(2) The air pipeline is blocked or discounted, but the gas is not available;

(3) The horizontal height valve connection rod falls off;

(4) The horizontal height valve is damaged.

Treatment method:

The air source of the air trailer suspension is connected by the brake system, and stored in a special air reservoir through a pressure protection valve. Work through the filter to the horizontal height valve of the air suspension, and then to the left and right air bags. When the air bag is less or no air, as long as you find the right cause of the failure, you know where to start, and it is not difficult to solve.