With the continuous development of domestic logistics and transportation industry, the laws and regulations or standards related to commercial vehicles are becoming more and more perfect. According to gb7258-2017 national standard for safety technical conditions for motor vehicle operation, three axle barrier plate and warehouse grid semi-trailer must be equipped with disc brake and air bag suspension in order to get on the license plate or drive on the road smoothly. The introduction of the new regulations forced the market demand to change, and more and more car owners began to pay attention to the disc brake + airbag suspension axle.

But for disc brake, many car owners still have doubts. They believe that compared with the commonly used drum brake, the disc brake friction plate is small, so the temperature rises faster, the water can not be poured for rapid cooling, the braking torque is small, and the maintenance cost is high, which is not in line with the service environment of heavy load downhill in Mountainous Areas of China.

In fact, there are subjective and objective reasons for choosing disc brake as the officially designated braking mode. Let's talk about the objective aspect first.

At present, the ownership of three axle rail plate and warehouse grid semi-trailer in China is relatively high in commercial vehicles. The goods transported are generally low value-added products. Most car owners transport according to the upper limit of nuclear load, which increases the loss of road surface. In addition, the price of such vehicles is low in the industry, and the technical safety configuration is relatively low, so there are great hidden dangers in safety. Forcing this kind of vehicles to use disc brake + airbag suspension can reduce overload and improve safety factor to a certain extent.

Subjectively, it is the advantage of disc brake itself.

Although the friction plate of disc brake is smaller than that of drum brake, its heat sink is directly exposed in the air environment, there is no shelter from foreign objects, and the heat dissipation performance is higher. In this way, even continuous braking will not have too high temperature; Secondly, the heat attenuation performance of the disc brake is better than that of the drum brake. According to the experimental data, when the temperature of the friction plate of the drum brake reaches more than 300 ℃, the friction coefficient will decrease by about 40%, but the friction plate temperature of the disc brake increases from 100 ℃ to 400 ℃, and the friction coefficient hardly changes; After wading, the braking performance of disc brake vehicles can generally be restored by braking once or twice, but the drum brake vehicles have to brake more than ten times continuously, which is also advantageous; In addition, the brake response speed of disc brake is fast, and the brake should be sensitive compared with drum brake; Finally, the so-called "water pouring cooling" problem. In fact, from the technical level, water pouring to cool the brake drum is an unscientific way. Whether it is disc brake or drum brake, direct water pouring under high temperature may lead to damage to system components and serious safety accidents, which is really undesirable.

In view of the problem of "heavy load downhill" raised by car owners, relevant people introduced that in view of the diversity and particularity of road conditions in China, car owners in some areas can choose to install auxiliary braking hydraulic retarder on the basis of disc braking, so that under the condition of continuous long downhill, even if they do not step on the brake, they can ensure the stable driving speed of the vehicle. But the premise is that the "heavy load" mentioned by the owner is within the allowable range of nuclear load. If it is overload, it is very dangerous.

Trailer disc brake + air bag suspension has gradually become the standard configuration of semi-trailer, but how to choose is still a difficult problem for car owners. Especially after the rising demand in the market, some small workshops took advantage of the opportunity to produce some shoddy axles and sell them at low prices in the market, catering to the greed of some car owners. However, the axle is the key component of the trailer, which is directly related to the safety and efficiency of the vehicle. If the quality of the axle is unqualified, once it encounters heavy load or bumpy road conditions, the axle may not withstand the pressure, have problems or even break. At least it cannot drive, and it needs trailer or maintenance, or it may lead to safety accidents, None of them can be solved by saving hundreds or thousands of yuan by buying inferior axles.

Generally speaking, starting from raw materials, the production of a qualified axle must go through at least a dozen processes, such as raw material cutting, hot rotary rolling, axle tube forming, heat treatment, CNC processing, axle medium frequency induction treatment, precision grinding and so on, not including quality inspection, quality test and so on. The precision, dead weight, rigidity, wear resistance, bearing capacity, fatigue resistance and other properties of the axle produced in this way can meet the standards, and the problems in the later use process can be reduced or avoided. Usually, the unit price of a qualified axle is at least about 3000 yuan. Some big brands may be hundreds or thousands of yuan more expensive due to the brand premium.

When purchasing Trailer disc brake + air bag suspension, it is recommended that the owner first understand the strength of the manufacturer. Located in Liangshan quanpu Industrial Park, Shandong Darong machinery mainly produces and operates various trailer axles, axle assemblies, special axles and axle related accessories, which have been certified by ISO9001:2008 quality management system, It has successively won the honorary titles of "Shandong high tech enterprise", "consumer satisfaction unit", "A-level contract abiding and trustworthy enterprise", "safe and civilized unit" and "Jining five good chamber of Commerce".

The disc brake bridge produced by Darong machinery is made of high-strength alloy seamless steel pipe and integrated axle manufacturing technology. The axle weight is lighter, more solid and durable. With improved special technology, the axle bearing capacity and axle service life are greatly enhanced. The airbag suspension produced by Darong machinery is forged by 3D forming technology, which has obvious advantages in self weight, better toughness, reduces axle stress, adopts special sealing technology, prolongs service life, and also has advantages in cargo protection, driving safety and tire wear.

Up to now, Darong machinery has been deeply engaged in the axle R & D and manufacturing industry for more than 20 years and has become an old brand strength enterprise in the axle industry. The axles produced by Darong machinery have won wide welcome from users at home and abroad with high quality and high cost performance. The annual output is more than 170000 pieces, and the business scope covers more than 50 countries and regions nationwide and overseas.