The low flat axle is a typical semi-trailer support axle, which is often referred to as the rear axle. It plays the role of bearing, braking, maintaining driving, etc. Different from the ordinary semi-trailer axle, the low flat axle is a special axle, which is different from the ordinary axle in appearance and performance.

2. Characteristics of low flat axle

Because of the low ground clearance of the low flat axle, it is beneficial to reduce the center of gravity of the vehicle to a certain extent, and it is more convenient for goods to get on and off, and the driving stability has also been improved accordingly. When the vehicles transport super high goods on the road with height limit, the trafficability will be stronger.

Secondly, the wall thickness and strength of low flat axle are higher. Compared with ordinary semi-trailer axle, the wall thickness of 20Mn2 seamless steel pipe selected for low flat axle is higher, which can be seen intuitively from the cross section of axle pipe below:

Not only the axle beam, but also the wheel hub, brake drum, friction plate and other accessories of the low flat axle are all dedicated, and their strength, toughness and wear resistance are fully up to standard.

3. Application field of low flat axle

Low flat axle is mainly applied to low flat semi-trailer.

Low plate semi-trailer is commonly known as "big plate car" in the industry. This kind of vehicle is specially used to transport heavy trucks, rail vehicles, mining machinery, forestry machinery, engineering machinery and other large goods that cannot be disassembled, and can also be used for the transport of car transport vehicles.

5. Key production process of low flat axle

① One piece heat treatment molding process

The so-called one-piece axle refers to the axle beam and axle head directly made from a complete steel pipe. Through the heat treatment process, the raw materials are heated to a certain temperature and kept to reduce the hardness and improve the plasticity, and then the axle beam and axle head are molded through the molding process, and finally the selected speed and method are used for cooling. The connection between the axle head and the axle beam formed by one-piece heat treatment is more natural and solid, which can not only fully avoid welding deformation, ensure the accuracy and parameters of the axle body, but also reduce the dead weight of the axle body, enhance the connection strength between the axle head and the axle beam, and fully avoid the problem of deformed bending of the axle under high strength load bearing.

② Fully automatic quenching and heat preservation tempering

Quenching and heat preservation tempering is a common process in steel processing. The mechanical properties of steel can be obtained through this process, which belongs to a controllable heating and cooling process. The martensite structure can be obtained through quenching. Although it is hard, it is too brittle. Therefore, the quenching process is often followed by a heat preservation and tempering process, which can reduce brittleness, improve toughness, and achieve the effect of both hardness and toughness reaching the standard.

③ Shaft head fine grinding and intermediate frequency strengthening

The shaft head is the key part connecting the wheel end parts. The higher the machining accuracy, the better the performance of the bearing, wheel hub, brake drum, etc. installed subsequently. This precision control is often refined to every drill hole or thread.

In addition, the intermediate frequency strengthening treatment of the shaft head is also essential, especially for the bearing connection parts. Only when the strength is fully guaranteed, can the performance output be more stable at high frequency speed.

④ Automatic assembly of axle

This is the most complicated process on the axle production line, involving dozens of types and hundreds of parts. In order to ensure the quality of finished products, the brake drum, wheel hub, bearing and other key components selected for the Darong low flat axle are all supplied by powerful domestic manufacturers and have undergone multiple quality tests. The assembly line has a high degree of automation, assembly parameters and parts are all traceable, and the quality is stable and reliable. At the same time, it has the characteristics of long service life, long maintenance cycle, and convenient maintenance.

6. Low maintenance frequency of flat axle

7. Common faults and troubleshooting