Entering the hall opposite, Du Zhongxiao pointed to the picture on the wall next to him and said, "Xianggong, this is the frame we made here." It's clear what parts a car needs and what is most important. ”

The picture is an axonometric drawing drawn by Du Zhongxiao himself, which is not detailed, but it is enough for workers to understand the structure of the car. In the words of later generations, the most important product here is actually the chassis of the car, and the upper trunk is very crudely made.

From the painting on the wall, Zheng Jian can roughly see the structure of the cart. In fact, it is a long axle, two wheels, and the axle is embedded in the top of the trunk.

Zheng Jian was not much interested in these specific technical details. Seeing that the craftsmen inside were busy, they walked in.

In front of him was a hydraulic forging hammer sticking in from the outside, Zheng Jian saw it and pointed to Du Zhongxiao and said, "This forging hammer for striking iron is extremely easy to use." Since that Tao 17 arrived in Xiangzhou, he has made many of them, which is very effective. A few days ago, I painted and painted graphics, sent them to various roads, and let them be made in the same way. ”

When he became an official in Xiangzhou, Tao Qiqi was different from before, and many of the things that Du Zhongxiao learned here were used by him in practice. The hydraulic forging hammer is the most obvious effect, and the imperial court deliberately drew pictures to deceive them into booklets and distributed them to various ways. It's just that it's doubtful what really works.

It was not easy to see something familiar, so Zheng Jian stepped forward to watch it carefully. I saw a craftsman cut off the thick steel bar of chopsticks after it was burned red, and a craftsman picked it up in time and put it into a disc-like mold. When it is full, put it under the forging hammer, and the forging hammer falls, pressing the short steel strips inside into small cylinders. Pick up the mold and shake it and set it aside.

Zheng Jian is a person who doesn't like to talk, he can't understand, and he doesn't ask Du Zhongxiao about it, he just reads it.

Later, there are craftsmen riding horses, and there is a small platform in front, pick up a short pillar and put it on, and clamp it on both sides. With the exertion of both legs, the place where the short columns were clamped on the table spun rapidly, and a steel tip next to them sharpened the cylinders extremely smooth.

After cutting, there is a quenching place behind to quench these small cylinders. In the back, the same as before, the small cylinder was clamped again, only this time instead of a steel tip, but with a fine abrasive cloth, the cylinder was polished smooth.

Zheng Jian watched it with relish, until he saw that in the end, these small cylinders were loaded into a copper frame with holes one by one and loaded into a steel ring.

Finally, looking at a round cup of parts packed together, Zheng Jian asked Du Zhongxiao: "Zhijun, what is this?" Where is it used? It looks so cumbersome to do, and it costs a lot of money. ”

Du Zhongxiao said: "Xianggong is right, this thing is indeed expensive. The cars we sell are worth the money on these little things. This thing is a bearing, also known as the axle, which is installed at both ends of the axle, and the wheel will turn quickly and effortlessly. ”

This is the simplest cylindrical bearing, the accuracy of this era is not good, so it has to be made coarse and bulky, and the principle is the same. There is no technical difficulty, the key is to use good steel, otherwise it is better to use a wooden shaft with a cast iron bushing. The cart that uses this kind of bearing can pull hundreds of kilograms of goods, otherwise where can a horse move. The carts produced by the Volcano Army are now mostly horse-drawn horses, and they are about 1,000 catties on a good road. The largest is three sets of carriages, one horse in the middle, one horse on each side to drag, can pull two or three thousand catties. Such a big car, without bearings, it can't move. With bearings, the car is durable, otherwise it won't be long before the axle breaks when pulling heavy loads.

The load of the car is closely related to the bearing, and without the rolling bearing, the support point of the shaft is deformed by the car and is extremely difficult to pull. Large carts need to use multiple wheels to share the load, which is related to this. If the bearing technology is passed, of course, the fewer wheels the better, reducing the consumption of parasitic power between the various axles and wheels. There used to be three sets of carriages in northern China, the key was rubber wheels and bearings, and three ordinary horses could carry several tons. In this era, there is no way to think about rubber wheels, so you can only start from the bearing, and it is very considerable to pull more than a thousand catties in a car. If you use a spring to absorb the shock, you can pull it more.

With this kind of big car, there is the motivation to build roads, otherwise it is worthless to build roads wide and straight. Only take the trolley, as long as the sheep intestine path is fine, the human back and the animal pack is simpler, as long as you can walk.

Du Zhongxiao also had a practical lesson, so he worked the bearing. At the beginning of the big car, it is a wooden axle with a cast iron sleeve, after lubrication, it is good to be lightly loaded, once it is heavily loaded, it is very difficult to pull a horse, and the wooden axle is quickly worn out. Switching to iron shafts, the price went up, but the lubrication effect was much worse, and the shaft heads were all immersed in oil, and the damage was very frequent.

Zheng Jian nodded, although he didn't quite understand, he didn't ask, and continued to read.

Behind is the axle making, wrought iron, also took over a turning program, smooth at both ends.

In the end, the front bearings are smashed into the grooves left by the wheels, and the two wheels are mounted on both ends of the axles, and the chassis of a large car is made. This is the most critical part of the cart, and as for the trunk, it is the carpenter's job. The trucks are not particular and are made directly from miscellaneous wood.

Zheng Jian watched the craftsman push the installed chassis from the hall to the outside, ran fast, and nodded: "This car looks good, the wheels are extremely light." Zhijun, how much cargo can a car like this pull? ”

Du Zhongxiao said: "Back to Xianggong, a horse that is usually unbearable to ride can pull 800 to 1,000 catties." If you use a good mule, you can pull 1,500 catties, which is far better than an ox cart. With this car, the goods from the Volcano Army to the Baode Army cost not much money. ”

Zheng Jian was taken aback: "How much can you pull so much?" In this way, dozens of miles a day, horses are not wasted. ”

Du Zhongxiao arched his hand: "The car with these wheels will not be like this." Generally, the goods are pulled for 30 miles and a break, and the day can travel 60 miles, and after a night of rest, the horse will be restored to the same as before. Of course, it would be better if you used a mule. ”

The mule drives the horse-drawn set, the mule is more docile than the horse, and in the carriage of the three sets, the mule is used in the middle, which can save a lot of effort. In the days when automobiles were not common, such horse-drawn trucks were once very common in northern China, supporting a vast logistics system.

Zheng Jian nodded, skeptical. Du Zhongxiao said two points that he paid attention to, one is that he can pull a thousand catties, and the other is that he doesn't need a good horse. At present, the grain and grass transported on Hedong Road mostly rely on people and horses, and the cost is frighteningly high. One person, one horse, one thousand catties, sixty miles a day, the cost of transporting grain and grass to Linfu Road dropped all of a sudden. And this car doesn't have to use good horses, there are a lot of horses here on Hedong Road, and it is easy to buy.

In the era when there were no automobiles, horse-drawn carriages were once the most important means of long-distance transportation in northern China, comparable to ships in the south. Localized mules and horses are resistant to rough feeding, and the coachman can travel hundreds of miles as long as he brings a little concentrate and feeds hay along the way, which is extremely convenient. If there is a highway, it is even more difficult to use rubber wheels, and a car can carry thousands of catties. In this era, rubber wheels can't be helped, but dirt roads are still okay.

Zheng Jian kept this number firmly in his heart, and thought about what way to use to promote the experience of the Volcano Army here, so that the states of Hedong Road could build more big cars and build roads. As for the most valuable, factory-based production method in this factory, Zheng Jian directly ignored it.

In fact, in Du Zhongxiao's eyes, the value of the bearing manufacturing process is greater than that of the carriage. This is the most humble factory, the product is single, the process is simple, if all the auxiliary systems, such as design, management, production, etc., can be complete, a standardized factory will be established.

Some simple, commonly used and very valuable parts can be produced in this way, suitable for large factories and family workshops. The value of such a system to society is immeasurable. It's a pity that Du Zhongxiao's current status can only be made into a rough and simple bearing, supporting some thick and bulky carriages here. The more complex stuff is beyond the scope of the power.