On January 5, 2012, the Ministry of industry and information technology issued a notice requiring dangerous goods transport vehicles and trucks with a total mass of more than 12 tons to be equipped with retarders or other auxiliary braking devices. As soon as the notice came out, "heavy truck installation retarder" became the focus of public opinion for a while. Many multimedia and industry experts expressed different opinions on whether heavy truck users choose eddy current retarder or hydraulic retarder, and whether the advantages of retarder are greater than the disadvantages or the disadvantages are greater than the advantages. What is the function of heavy truck mounted retarder? Will the cost of heavy truck users increase after installing the retarder?

Domestic heavy truck retarder market is opening up

Retarder is an auxiliary system of automobile brake. When the car is decelerating or going down a long slope, the retarder can be used to decelerate smoothly and avoid the wear and heat caused by using the brake. There are two kinds of retarders in the market: eddy current retarder and hydraulic retarder. The retarder can play a good auxiliary role in the braking of heavy-duty vehicles, especially in the places where there are many mountain roads or slope roads.

At present, the retarder is mainly used in large passenger cars, but not in heavy trucks. But with the continuous opening of the market, the retarder has attracted more and more attention in the domestic heavy truck market. Nowadays, with the promotion of policy, the domestic heavy truck retarder market is opening up.

Hydraulic retarder is the trend

Compared with eddy current retarder, hydraulic retarder has incomparable advantages in self weight, continuous braking and energy saving. First of all, in terms of self weight, the weight of hydraulic retarder is only about 50kg (the weight of eddy current retarder (2000nm-3200nm), which is suitable for trucks of more than 12t in China, is generally 100-450kg).

Second, compared with eddy current retarder, the hydraulic retarder needs to save friction plate. When the eddy current retarder is running, it is cooled by wind, resulting in rapid temperature rise and obvious decrease in braking efficiency. However, the temperature rise of the hydraulic retarder is not obvious due to water cooling, which is almost invalid, and it can be ready for full load operation at any time. The test shows that the hydraulic retarder saves 2-3 times of friction plate than the eddy current retarder.

Third, the Hydraulic Retarder's good heat dissipation ability makes it particularly suitable for the continuous braking conditions required by Changpo, which is the only solution to solve the mountain braking failure at present.

Fourth, the hydraulic retarder vehicle is superior to the eddy current retarder vehicle in terms of weight, inertia, maintaining a more reasonable engine running speed and maintaining a higher downhill speed, and the fuel consumption ratio is nearly 2-5% less. For this reason, the application of eddy current retarder in Europe was further reduced in the 1990s, and it was basically withdrawn from the European market a few years later.

Hydraulic retarder reduces weight and saves tire

Although the hydraulic retarder has many advantages, it is still not popular in the domestic heavy truck market. The first reason is that the safety has not been paid so much attention before. The second reason is that the installation cost is high and the investment value is far from being widely recognized by the market in the short term.

With the increasing attention, investment and competition of domestic and foreign enterprises to the market, the cost of various types of retarders is in the decline channel. At present, the market price of special hydraulic retarder for truck is close to that of eddy current retarder with the same torque, but its performance is better than that of eddy current retarder.

More importantly, the use of hydraulic retarder can help truck users reduce more transportation costs. Trucks operating in mountainous areas are equipped with a water tank, which is mainly used to spray water on the tire rims to reduce the temperature. Generally, 400 kg-1200 kg is needed. "Drivers who often run on mountain roads know that when driving in mountain areas, they often encounter the situation of continuous braking. In the absence of hydraulic retarder, continuous braking causes the temperature of friction plate and rim to rise rapidly. In order to ensure the braking effect, water is needed to cool down."

The reporter simply calculated that according to the current domestic minimum freight of 40 cents, a heavy truck should run at least 60000 kilometers a year. According to the minimum standard of water tank capacity, after the hydraulic retarder is installed, the water capacity can be reduced by at least 300 kg, so as to reduce the load of the whole vehicle and let the vehicle pull more 300 kg of goods each time. According to the calculation, 0.3 (T) x 0.4 (yuan) x 60000 (km) = 7200 yuan, that is to say, after the hydraulic retarder is installed, the vehicle can pull 300 kg more goods each time, thus making at least 7200 yuan more each year. If it is calculated by 1000 kg water tank, it is 21600 yuan.

In addition, according to the reporter, in Shanxi and Datong, where there is a shortage of water, there will be a family style water station on the mountain road, which costs about 20 yuan to add water at a time. What's more, water needs to be queued up to delay transportation efficiency, which is undoubtedly an increase in transportation cost. Nearly 5000 yuan of unnecessary waste is converted into income in a year, which is not a small economic account for truck users.

According to the introduction, the hydraulic retarder can not only reduce the self weight, but also help the truck effectively protect the tires. Tire is the most frequent item in the daily maintenance of heavy truck. As we all know, the material of tire comes from rubber. Because of the characteristics of rubber itself, the service life of tire is closely related to the temperature. Braking for a long time in the mountain area will bring high temperature to the tires, which will cause great tire loss. Therefore, there is a saying among the drivers who often run on the mountain road that "one foot slams on the brakes, three days less tires".

According to the previous survey, at present, the cost of heavy truck tire is about 3000 yuan. The replacement cycle of front wheel tire is generally 8 months, and that of rear wheel tire is 3 months. can