China's automobile ownership has continued to grow.
In recent years, China's automobile ownership has continued to grow. At the same time, policies and regulations have placed higher demands on the safety of the freight industry. On September 29, 2017, the GB7258-2017 "Safety Technical Conditions for Motor Vehicle Operation" issued by the National Standardization Committee clearly stipulates that all wheels of all dangerous goods transport semi-trailers should be equipped with disc brakes from January 1, 2019. As of January 1, 2020, all wheels of all three-axle Side Wall Semi Trailer and Fence Semi Trailer should be equipped with disc brakes.
As we all know, the performance of disc brakes is closely related to vehicle safety. At present, in the domestic dangerous goods transport semi-trailer market, although the disc brakes have become standard, the disc brake products on the market are mixed. There are still many questions like how to select, how to maintain the disc brake axles, and how to match tractor and semi-trailers equipped with a disc brake, etc., to the users.
As the world's top supplier of commercial vehicle parts, Safholland has accumulated a wealth of experience in trailer disc brakes and air suspension to ensure excellent and reliable products and services. In terms of disc brakes, Safholland has a core patent-brake disc composite casting technology.
Saf composite casting brake disc
The Saf composite cast brake disc features a lower air duct design–there are 10 ventilation slots in the lower part of the brake disc to promote heat dissipation. There are more ventilation slots inside the brake disc to facilitate the timely diffusion of internal heat. In addition, the contact area between the brake disc and the disc is small, which significantly reduces heat transfer. These advantages make it difficult to transfer heat to the shaft end of the brake disc, thereby avoiding high-temperature damage to precision components such as axle bearings.
Ventilation cooling under the composite casting brake disc
The Saf brake disc composite casting technology can avoid the umbrella deformation caused by the brake overheating of the brake disc, and eliminate the local overheating and the cracking of the brake disc caused by the uneven contact between the brake disc and the friction disc, thus prolonging Brake disc and friction plate life. It also enhances the Braking stability, making driving smoother and safer.
Composite casting brake disc only for radial expansion
However, the traditional one-time casting brake disc is difficult to avoid the umbrella-shaped deformation caused by the brake overheating. This deformation will cause unevenness between the friction disc and the brake disc, which will affect the braking stability. Vehicles are prone to danger under severe conditions.
Umbrella deformation of the traditional brake disc
A comparative analysis of the composite casting brake disc and the conventional brake disc was carried out through 500 thermal cycle tests. It can be seen that in the use of the composite casting brake disc, the brake disc is only radially expanded to be in full contact with the friction plate, the heat distribution is uniform, and the brake disc has no obvious crack. The life of the friction linings and brake discs is significantly improved, which significantly reduces operating costs and ensures safe driving.
A composite casting brake disc (left) and traditional brake disc (right)
Thermal distribution comparison
With the axle of the traditional brake disc, the brake disc and the friction disc wear unevenly, the heat distribution is uneven, and the local overheating will eventually cause the brake disc to crack significantly. The life of the friction plates and brake discs will be significantly reduced and the safety will be greatly reduced.
A composite casting brake disc (left) and traditional brake disc (right)
Cracking comparison
According to the technical characteristics of the brake shaft of the Saf disk, in order to give full play to the advantages of the brake shaft and ensure the safety of the vehicle, the matching effect of the tractor and semi trailer recommended by Safholland is as follows:
| Tractor | Semi-Trailer ( Disc brake) | |
| EBS + disc brake | EBS：very good | ABS：good |
| ABS + dis brake | EBS or ABS：good | |
| EBS + brake drum + retarder | EBS or ABS：good | |
| ABS + brake drum + retarder | EBS or ABS：good | |
| EBS + brake drum | EBS or ABS：acceptable | |
| ABS + brake drum | （install retarder and brake lining wearing indicator is strongly recommended for special road condition) | |
In addition to the tractors that have been required to install the retarder in the above table, Safholland strongly recommends that the other tractors listed also have a retarder. In addition, the disc brake shaft is not allowed to be water cooled.
At present, the Saf axles using brake disc composite casting technology have been assembled on a large number of European and American semi-trailers, which has become the best choice for the operation and efficiency of the majority of fleet drivers. In the future, more and more domestic semi-trailers need to be equipped with disc brakes. Safholland will provide customers with more and more axle products using brake disc compound casting technology, and make progress for the development of China's commercial vehicle industry. A new outstanding contribution.
European semi-trailer equipped with a brake shaft
Introduction to Safholland
In 1881, Saf originated in a rural forging workshop in Germany with the invention of a new type of the plow; in 1910, the Holland company was born in the United States for the invention of a safe release tractor. At the end of 2006, the two companies merged and reorganized into the Safholland Group, becoming the world's most comprehensive and wide-ranging manufacturer of commercial vehicle parts.
The Safholland Group is a publicly-traded company headquartered in Bersenbach, Bavaria, Germany, with 41 subsidiaries, 22 production sites, more than 4,400 employees and more than 11,000 service outlets worldwide. Group trailer products include axles, air suspensions, mechanical suspensions, outriggers, traction pins, couplers, etc. Truck passenger car products include an air suspension, saddles, etc., and the market share of products is among the best in the industry.
The Safholland Group has strong product development capabilities and has a research and development center in North America and Europe. The China R&D Center is currently under construction. Through its own development and continuous mergers and acquisitions, the Group's sales have grown rapidly in recent years and its business has continued to expand. The current group holding brands include SAF, Holland, Neway, V.Orlandi, Copco, KLL, York, Axscend, PressureGuard and Stara.
The Safholland Group attaches great importance to the Chinese market. In order to support the rapid development of its business in China, the Group has invested in the construction of a new factory based on Industry 4.0 in Yangzhou, China. In the future, Safholland will continue to adhere to technological innovation, continuously improve product quality and service quality, and enhance competitive advantage. In the new era of commercial vehicles moving toward lightweight, electric, intelligent, and networked, we continue to provide innovative, high-quality products and services to our customers.