For these high-precision ball screws, the production process maintains even more precision than the high-precision production equipment.

Yun Fei doesn't think that the production process used by countless manufacturers in the world will not be able to guarantee the accuracy of the ball screw.

"The main problem in the production of ball screws is not only the material. But now all we can control is the arrangement of the production process. I suppose in your Soviet Union, the production process is also very important, right? This is especially true for these parts with a high degree of precision. Of course, for you, I don't require you to be able to produce a ball screw with zero precision according to the Chinese national standard, but you have to produce a ball screw of at least three levels for me! Otherwise, how can you be worthy of your annual salary of 12,000? ”

The work of the ball screw factory was not very heavy, but it was necessary to put some pressure on the proud mechanical engineer from the Soviet Union.

For the current production, Yunfei actually does not have such high requirements, as long as this factory can produce ball screws that barely reach the five-level accuracy level, it can meet the use of CNC machine tools produced by Jiuyi Heavy Industry. After all, in China now, the largest market is not high-precision precision machining CNC machine tools, but a large number of simple CNC machine tools.

The production range of simple CNC machine tools, generally the minimum tolerance will be more than eight wires, most of the mass-produced parts are produced in four or five wires or more, and even many are more than ten wires. High-precision grade machine tools, used to produce these requirements are not too high parts, not cost-effective at all, not only for the wear and tear of the machine tool, reduce the service life of the machine tool and the processing grade, more importantly, precision CNC machining machine tools, the price of several times or even dozens of times than simple CNC machine tools.

In Yunfei's world, there are millions of CNC machine tools in the entire country. More than 90 percent of them are the lowest-level simple CNC machines. At the same time, the value of the 90 percent of the lowest level of simple CNC machine tools, the sum of which can only be compared with the value of 10 percent of the high-end CNC machine tools.

In other countries, especially the United States, where the number of CNC machine tools is the largest, the number of high, medium and low-end CNC machine tools is about 1.5 to 3 to 5.5.

Therefore, if you want to produce CNC machine tools in China, the high-end market will never give up. Desperately want to bite a bite of fat, on the surface, the value is not very high low-end CNC machine tools, Yun Fei will not give up.

Now, when he is poor and has no foundation, Yun Fei does not expect to be able to produce mid-range or even high-end CNC machine tools by relying on the fact that he has seen a lot of CNC machine tools in later generations, and has also operated a lot of CNC machine tools and some theoretical knowledge mixed with Du Niang.

If it was really that easy, it would not be when he left his world, Huaxia had not yet produced high-end CNC machine tools in the real sense. China's real domestic enterprises can't even produce five-axis machining centers!

Since the goal is now the largest low-end CNC machine tool market in China. The low-end simple CNC machine tools with millions of uses, if you use those ball screws with an accuracy level of three or more, it is simply a big waste to kill chickens with a knife.

The production process of the ball screw arranged by Yunnon. It was more complicated than the current one, but it was easier to ensure machining accuracy than this. The ball screw production process designed by Yun Fei is several more than the production process in his own world.

He knows the production process of Du Niang. Although it can be machined, it is not possible to achieve a high level of accuracy.

Therefore, he added forging, rough turning, quenching and tempering, lathe finishing, and then carried out the arc spiral groove on the cold-rolled ball screw, carried out high-frequency quenching, and then arranged the finishing of the lathe before the most difficult grinding process.

This production process is not the cold-rolled ball screw (often called "rolling screw" in Europe and the United States) used in China. Most of them are made by batch conversion and rolling, and then made into ball screws of different lengths as needed. The pressing process of ball screw threads is mostly the same at home and abroad, and the processing technology of a single cold-rolled ball screw in the later stage is slightly different.

Most of Europe and the United States adopt shaft end hard turning technology, which is simple and efficient; At present, China is still mostly the traditional process of turning the bearing seat after the annealing of the shaft end, and the domestic production process is compared with foreign countries, whether it is from the use effect or the production and manufacturing cost, it is self-evident. The processing technology of quenched steel ball screw with large allowance processing is more flexible, which is convenient for overall production arrangement, and replaces the annealing process and secondary quenching processing technology; In addition to the exquisite appearance of the processed product, the shaft end part also reduces the unstable performance defects of the ball screw caused by multiple heat treatments.

Yun Fei was originally an on-site technician in the production workshop, and he knew better how to rationally use the existing equipment to achieve the highest production efficiency and the highest production accuracy than those who had just worked in the office with theoretical books for a lifetime.

He wanted to use the kind of hard turning process often used in Europe and the United States, but the current domestic tools could not achieve large-scale rough machining of the Rockwell hardness with a hardness of HRC58-62. The use of imported ceramic blades, the production cost is too high, the same way, the hardest diamond blades, can only be used for finishing, can not be used for rough processing at all, otherwise, the cost of the blade alone, will make the two of them invest four million blood!

Therefore, in the current situation, Yunfei can only use more complex processing technology to produce ball screws with a low degree of precision.

Anyway, Jiuyi Heavy Industry is his, and the costs of forging and heat treatment are just his own money from him and Wang Qingfeng in his pocket. Wang Qingfeng has nothing to say about this.

If Yun Fei hadn't been there to play with him, there would definitely be a production workshop specializing in the production of ball screws in the huge factory of Jiuyi Heavy Industry, if this was the case, Wang Qingfeng could only look at Yun Fei depressedly, Yun Fei, who spent one-fifth of his factory to buy a favor, made money every day.

He was very unfamiliar with the production process, especially the ball screw, which he had never touched before Yun Fei said it. The materials chosen by the Soviets and the precision that could not be achieved by the designed production process were achieved in a very short time after being changed by Yun Fei!

For the market prospect of ball screw, Wang Qingfeng now sees it. Especially now in the domestic CNC machine tool industry, after the emergence of the dragon system of Huadu CNC, a large number of foreign key accessories are exported to China, what a big profit! You must know that the ball screw is not other products, this is an indispensable key part of CNC machine tools!

Ball screws are sold in China, but rice is sold!

Calculate, the material cost of a ball screw with a diameter of 50 mm and a length of two meters is only three or four hundred yuan, plus various costs such as heat treatment, processing fees and factory management fees, but it is only about 1,000 yuan, but to buy it on the market, at least four or five thousand yuan!

According to China's ordinary machine tool market, even if China produces 50,000 CNC machine tools every year, if half of the factories buy ball screws from the factories of him and Yun Fei, Wang Qingfeng fainted happily when he thought of this data.

Moreover, a CNC machine tool can use more than one roller screw! Although the length is different and the specifications are different, anyway, in China in this era, the ball screw sells for 3,000 yuan per meter, and there will definitely be people rushing to buy it.

The ball grinding machine retrieved from the second-hand market in West Germany is more efficient after being improved by the old Maozi of Jiuyi Heavy Industry; The production of ball nuts is far simpler than the production of ball screws.

The connection between the ball screw and the ball nut is a circulating elbow designed by Sevianwski. Yun Fei didn't know what this connection method looked like at first, but when the ball screw, ball nut and ball were produced, and when he assembled it at the end, he found that this was actually the most widely used connection form in his world.

The so-called circulating elbow connection means that the ball returns to the screw and the nut through the circulating groove outside the nut after the end of the coiling process. This connection form is simple in structure, good in manufacturability, and the bearing capacity is relatively high, the only bad thing is that the radial size of the nut is larger, after all, there must be two layers of spiral grooves on the nut, which is used to continuously circulate the roller from the middle of the nut and the screw. However, this shortcoming, for the current Chinese CNC machine tool market, can not be called a shortcoming!

Of course, if you want to buy a ball screw on the market, you must not only sell a ball screw with a relatively high accuracy arc spiral groove, but also sell ball nuts and balls that are matched with the ball screw.

These things, when combined, form a ball screw pair.

Rongcheng Xinkaixing Ball Screw Factory, to sell, is the ball screw pair.

With Yun Fei, a person from later generations, the ball screw test of Rongcheng Xinkaixing Factory went very smoothly. In just over ten days, a sample of the ball screw that replaced the production materials and changed the production process was produced.

Although this inspection meets the design requirements in all aspects, whether it can use the needs of the market has to wait until Yunfei's Jiuyi Heavy Industry produces the first CNC lathe and uses it for a period of time. Therefore, now the main energy of the entire Rongcheng Xinkaixing has once again been invested in the business of CNC machining.

If Jiuyi Heavy Industry can produce CNC lathes, it will make the entire Rongcheng Xinkaixing Ball Screw Factory have a great development. Similarly, if this ball screw can ensure the stability of quality, the CNC machine tool of Jiuyi Heavy Industry will definitely quickly occupy the domestic market for international machine tools assembled with imported ball screws with low accuracy grades.

Everything is waiting for the first CNC machine tool of Jiuyi Heavy Industry to roll off the assembly line! (To be continued......)

PS: It's almost the end of the month, the monthly pass in everyone's hand, please vote for the gourd! Although the gourd has not broken out, I am embarrassed to ask everyone for everything, but the gourd has been working hard......