Chapter 218

"Chief, this is the gear and bearing I made. How about it?" With excitement on his face, Jack pointed to the big and small gears and bearings on the iron workbench.

Stone bear picked up two different sizes of gear, carefully looked up.

The two gears, one big and the other small, are obviously just cast, and have not even been polished. However, when Shi Xiong put the two gears together to mesh with each other, he found that although the two gears are not the same size, they mesh very well.

"Chief, I calculated carefully with the formulas you gave me, and then I got some data. Then I cast the mold according to these data, and I got these gears. Before you come here, I have simply tested these gears, and the results are very good. If you polish it again, the meshing effect between them will be better. "

"Good! Jack, these gears are very good. At least I can't see anything wrong with them. However, you need to carry out strict experiments and a long time of trial run before you can start the real application of these gears, otherwise it is easy to go wrong. "

"Don't worry, I will carry out strict experiments and long-term trial run. After all, these things are used in hydraulic machinery. Once there is a small mistake, it will cause great losses. "

Stone bear satisfied put down the gear in his hand, no matter what, he can see that these gears are absolutely carefully calculated and cast. Although Shi Xiong is not very proficient in this knowledge, he has learned something about it, and these gears give people a good feeling.

He picked up another bearing.

This is a large cylindrical roller bearing, but compared with gears, this kind of large cylindrical roller bearing is not enough to see.

Whether it is the inner ring or outer ring of the bearing, or the cylindrical roller inside, the processing technology can be seen very rough, and even two cylindrical rollers can be seen irregular with the naked eye.

Stone bear weighed the bearing with his hand and said, "Jack, our processing technology still needs to be improved. I'm afraid this kind of precision bearing will be scrapped in a short time."

Jack Williams's face turned red immediately. He muttered, "chief, I need time to improve the processing technology, but now the bearing you are holding is the best one..."

The stone bear nodded slightly, but said nothing.

Bearing has been around for a long time. The early transportation mode of placing a row of wooden poles under a row of skid plates was actually the earliest form of linear motion bearing. Last year, when the stone bear was working as an oil press to transport the big oak trunk from the hillside, a lot of rolling wood was put under the trunk. In fact, the principle of linear motion bearing was used.

Da Vinci also described the ball bearing at the beginning of the 16th century. In fact, the cage ball bearing described by Galileo in the 17th century was the earliest rolling bearing with cage; By the end of the 17th century, wallow had designed the real ball bearing.

Bearing is not very big, but it plays an irreplaceable role in mechanical manufacturing as gear. However, the accuracy requirements of bearings are much higher than that of gears. At least in modern times, the accuracy requirements of bearings are much higher than that of gears.

The gears that Shi Xiong saw just now are also cast, but with a little polishing, they can be used in some low-speed mechanical equipment. Although the bearing in hand is a cylindrical roller bearing, the machining accuracy requirement is not as high as that of ball bearing, but the machining accuracy of the bearing obviously can not meet the requirements.

But the stone bear can also understand Jack's problem. After all, this is an Indian tribe, which can be said to be a poor place. It's very good to be able to make the bearing in hand here, and the stone bear can't ask Jack to make a better bearing under the current situation.

At present, there are only two kinds of metal processing capabilities available in gaoshu tribe, namely, the most primitive sand casting and hammer forging. Other hot processing technologies such as injection casting, die casting, rotary casting and directional solidification are not available at all, let alone cold processing technologies such as cold rolling, cold drawing, cold forging, stamping and cold extrusion.

As for precision casting, it only exists on paper.

You expect to use sand casting to produce precision metal parts that can only be produced by precision casting. That's just a joke. If you want to use a hammer to forge precision parts, it's better to use sand casting

However, under the guidance of stone bear and Ferguson, Jack is now preparing to try the lost wax method. What's more, the lost wax method is a metal hot working process with the highest cleanliness under the current conditions.

I know this kind of thing is urgent. Just like in previous generations, the metal processing technology has been improved for hundreds of years, but the machining accuracy is still limited. This is the most basic thing. You can't be anxious if you want to. You can only do it step by step.

However, stone bear also knows that he has golden fingers, and this process will be greatly shortened, but he can't be in a hurry.

It's like the bearing in hand belongs to the type of bearing with a stop on the outer ring. The casting of the inner ring and outer ring is OK. At least the two rings look very round.

But the rolling element inside, that is, the 15 cylindrical rollers, is really a bit ugly.

Bearing is a kind of support body to support the rotation of machinery. Whether it is high-speed rotation or low-speed rotation, the friction coefficient and rotation accuracy are strictly required. The smaller the friction coefficient and the higher the rotation accuracy, the better the bearing.

But whether it is the friction coefficient or the rotary accuracy, it depends on the machining accuracy of the whole bearing, especially the rolling element.

But Jack made the cylindrical roller of this bearing, the machining accuracy error is really visible to the naked eye. It is no exaggeration to say that this kind of cylindrical roller is like later generations cutting a steel bar into several sections and then inserting it between the inner ring and outer ring of the bearing.

The stone bear could only shake his head helplessly and said, "Jack, try to cast this kind of cylindrical roller with the lost wax method."

Although the lost wax method was mostly used to cast bronzes in ancient China, it is undeniable that the casting accuracy of lost wax method is much higher than that of sand mold casting.

Even when Ferguson cast the barrel of a new rifle, he used the lost wax method.

"Well, pay attention to communicate with Ferguson. He has a deep understanding of the foundry technology in this area."

Jack nodded his head quickly to show that he knew

PS: bow to thank "the first kiss to the hand" 2000 reward!