One day more than a decade ago, at the machining center of the 811 factory (later merged into the Rocket Institute) of the China Academy of Launch Vehicle Technology (hereinafter referred to as the "Rocket Institute"), several people dressed in lock tooling gathered around a milling machine to watch the operator's movements. The milling machine was very clean, and the parts on the fixture were much larger than usual, tightly wrapped, with only one groove exposed. The operator, Hu Xu, held his breath and started the milling machine, and the people around him also held their breath. The flying milling cutter is gradually falling, and it is time to eat the groove! In the blink of an eye, the milling cutter has slowly risen, and ordinary people do not even have time to see the action of the milling cutter "touching" the groove. Hu Xu calmly shut down the machine, and carefully used a cotton swab to dip out the trace amount of debris in the groove, and the groove was smooth as a mirror.
"It's done!" Everyone was relieved, and they witnessed a moment of great significance - Hu Xu completed the "minimally invasive surgery" of using a milling machine to perform a "minimally invasive operation" on the finally assembled launch vehicle servo mechanism.
Hand sharpen the knife, mill the parts from the heart
So far, Hu Xu, a master of 18 skills of the Rocket Institute, has been in the field of milling, "carving" parts for nearly half a century, and doing "minimally invasive surgery" for servo mechanisms is the epitome of his profound skills.
Laymen may not understand why milling a part is like surgery on a person, layer by layer, carefully? The reason is simple – because this part is "heavenly".
As the "executor" of the rocket's control command, the servo mechanism is like the "rudder" of the rocket, and it must accurately swing the thunderous engine to the predetermined direction in a very short period of time, and the slightest deviation will make the rocket "fallacious". Whether a precise and reliable servo mechanism can be created affects the development level of the launch vehicle and also reflects the strength of a country in precision processing.
Where does the confidence to do "minimally invasive surgery" for servo mechanisms come from? Hu Xu has two unique skills - hand-sharpening milling cutters and manual precision milling.
"If you want to make the parts smooth, you have to make the knives cleaner." Hu Xu has sharpened more than 700 milling cutters of various types, and the thinnest milling cutter is only the thickness of the needle, but he can still mill out two smooth sides of the cutter head.
△ Hu Xu grinds the drill bit by hand
The fine knife is in hand, and the strength of the knife is familiar with the heart, which allows Hu Xu to face complex parts with a milling error of 0.01 mm and "not exceed the moment from the heart".
Small details, atmospheric knots, cast the spirit of craftsmanship
How do you practice your skills? Hu Xu did not answer the reporter directly, but recalled a past event. At the end of April 1970, when 15-year-old Hu Xu was apprenticed at a military factory in the Central Plains, the master was an "eighth-level worker". "At that time, in the understanding of many people, the apprentices of the 'eighth-level workers' had to do a better job than the apprentices of the 'sixth-level workers', and they were good in all aspects." Hu Xu said, "In the morning, I will come earlier than the master, wipe the milling machine clean in advance, pack all kinds of tools, put good oil on the machine, fold the rags, remember what I learned yesterday, and wait for the master to come." Inheriting the sense of honor of the traditional craftsman culture, Hu Xu started from the details and gradually grew into the most skilled among the workers who entered the factory in the same batch.
In addition to doing a good job of details, the craftsmen of the new era have the atmosphere of "home and country". Also in April 1970, Hu Xu and his friends, who were about to enter the factory, heard an exciting news - China successfully launched the first artificial earth satellite. Hu Xu's parents, who once served as technical management cadres at a military factory in the northeast, often told him the truth that "if you are backward, you will be beaten," and you often recalled the situation when he and the workers "rotated" to build weapons for the volunteer army. Under the influence of his parents, Hu Xu had a deeper understanding of the country's scientific and technological achievements and was also encouraged. Hu Xu thought to himself that although building rockets and satellites is "unattainable," he can also contribute to national defense and the development of science and technology in his post. This mentality gave him solid skills to later join the aerospace industry. In 1985, Hu Xu, who had been transferred to the Capital Iron and Steel Factory, immediately signed up after hearing that the 811 factory of the aerospace system was recruiting millers.
Delve into CNC to set a precedent and cultivate talents to pass on experience
In that year, the Rocket Institute 811 Factory adopted the method of technical examination and interview to select talents. Of the more than 60 people who signed up, only 3 were admitted. Hu Xu ranked first in his achievements and entered the aerospace industry that he had "longed for for a long time" as he wished.
Although experienced, the precision of the servo mechanism parts still opened Hu Xu's eyes. He modestly learned from his predecessors and colleagues and quickly met the requirements of the post. The leader saw that Hu Xu was self-motivated, humble and young, so he asked him to "try" a CNC milling machine that had not been opened and only had a foreign language instruction manual. Hu Xu looked around for information and communicated with young people in charge of testing CNC milling machines in other units of the Rocket Academy, and also used the only "286" computer at that time to supplement the computer foundation. Not long after, Hu Xu really opened the CNC milling machine and became the first person to CNC machining the servo mechanism of the rocket institute.
Hu Xu said: "Looking at it now, the CNC milling machine can only be regarded as a device with some automatic control on the traditional milling machine, but the work efficiency has made a qualitative leap. Every time a batch of parts comes, the factory will let me mill a little, and then gradually increase the size. In the end, the speed and quality of the CNC milling machine exceeded that of the manual milling machine, and the factory decided to concentrate the CNC machine tools of other plants, and then extracted the backbone from each workshop and established a CNC machining center. ”
△ Hu Xu in front of the CNC milling machine
Since then, Hu Xu has begun to teach CNC milling technology. As the team pulls up, the efficiency increases day by day. "Previously, the servo mechanism has always been one of the 'short boards' in the production progress of launch vehicles, and the processing of precision parts is the 'short board' of the servo mechanism. CNC 'on the horse', the situation has greatly improved. In 1989, we snatched up the servo mechanism of the 'long two bundles of rockets' in just a dozen months, which was unimaginable before. Hu Xu said: "However, the manual milling machine has not been completely eliminated, and it is now used to specialize in more precise or newly prototyped parts." ”
△ Hu Xu is guiding young people who are about to participate in the skills competition
Since the late 1980s, Hu Xu, who has emerged in several skill competitions, has become one of the coaches of the Rocket Academy Miller Competition. So far, he has directly brought out more than 20 apprentices, and even more have indirectly imparted experience. Hu Xu summed up his experience into more than 10 articles, which were published in technical journals at all levels; he also made his experience into a PPT to make the newly hired "post-90s" employees more acceptable. At the same time, Hu Xu also made friends with peer elites outside the space system, actively promoted exchanges and cooperation between the Rocket Institute and external enterprises and universities, and let the top skills converge into a steady stream of living water, which not only irrigated aerospace, but also nourished the industry. He also often participates in machine tool exhibitions, grasps the latest developments in the development of CNC machine tool equipment at home and abroad, and provides suggestions for unit upgrading equipment.
Hu Xu said: "It is my greatest wish to give all the experience and contacts accumulated over the decades to young people. ”
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