For the sake of security, the dormitory of the veteran is in the courtyard of the United Processing Center. In addition, the equipment of the joint processing center has not been used by naturalized migrant workers until now - to operate this equipment, at least the foundation of high school mathematics in the old time and space must be used, and at most the workers who have obtained a type B diploma will not be able to play it.

The dormitory is a suite, with a small bedroom inside, and a living room and studio outside, but it is actually more used as a meeting room. The patriarchs of the factory often discussed the jishu issue here. In the middle of the house is a large table of eight immortals, surrounded by rattan chairs and benches. Against the wall there is a fitter's table with a vise fixed to it. There was also a locked tool cabinet - inside which were his personal tools.

After the whistle sounded at 6 o'clock in the afternoon, Zhan Wuya first checked the fire and safety conditions of the workshop and the pipe products warehouse of the United Processing Center, and confirmed that the power supply had been cut off, and the doors and windows were all locked. It's a daily routine. As the director of manufacturing and the director of the general machine factory, he holds the keys to both places and is directly in charge. Zhan Wuya knew that there was not much danger of being destroyed by force, and what he was most afraid of was a safety accident, especially a fire.

Everything was in order, and he took care of his female apprentice to go to the veteran's canteen to buy supper and drinks for the evening, and prepared to work at night to continue to tackle key problems - the female apprentice was actually his maid, Zhan Wuya felt that he had lived in the factory for a long time, and it was useless to make a maid in vain, so he simply stayed under his hand and worked as an apprentice.

Take advantage of the fact that everyone has not yet come. Zhan Wuya took a few damaged chains from the workshop to the workbench outside, turned on the workbench lamp, and carefully checked the broken edge of the chain. I looked at it with a magnifying glass for a while. He himself is engaged in heat treatment, although he does not understand metallography, but the accumulation of years of experience has allowed him to explore a little bit in this area. After looking at the fracture for several minutes, I felt that it was still a problem of the force of the material.

After a while, everyone came, and looked at the broken chain link again and again. Discuss how to increase the strength of the chain. It should be said that this time the General Machinery Factory is ruthless to take down this link of the industrial chain, and Zhan Wuya personally engaged in heat treatment -- specially built a large-scale heat treatment furnace. The steel obtained from the Ministry of Metallurgical Industry is also the best product that steel mills can produce.

But the results were still not satisfactory. Everyone looked at the big chain repeatedly, and joined a few words of discussion from time to time. Liang Xin took the vernier caliper, measured the chain links one by one, and wrote down the data on a piece of paper. Sun Li checked the chain section by section for scars...... Everyone is busy studying the chain from all angles, and there is no discussion until an opinion has been formed - and the hypothesis must be based on physical evidence. Zhan Wuwu's female apprentice added tea to them, and from time to time helped light the fire and empty the full ashtray.

In the middle of the night, everyone finally came up with a unified jishu analysis conclusion: the chain is stressed unevenly. The main cause of the problem is a problem with the manufacturing process.

The process flow of the manufacturing chain of the machinery factory is to first forge the blank, then annealing and stress relief, then cutting, then normalizing modulation and surface treatment, and assembling it.

"I just checked a lot of knots of the chain, the tolerance is not very ideal, there are large, the average error in the size is still relatively large, according to the GB standard, the limit tolerance of this size chain link can not be greater than this shows that the prestress problem in the cutting process is more serious than we imagined." Liang Xin said, "A small amount of tolerance accumulates, causing a certain section of the chain to be stressed intensively and eventually breaking. ”

Sun Li said: "I think it should be processed first and then heat treated, even if it costs a little tool, it is also accounted for - after all, we can always solve the problem of tools in the future, not a one-time consumable that cannot be replenished when it runs out." In addition, the forging was still handed over to the arsenal to do, where the forging machine was larger than here. With such a high-strength industrial chain, the larger the tonnage of the forging machine, the better. ”

"The manufacture of superhard tools on the lathe will not be solved for a while. I don't know if I can do it before the end of the first five-year plan. Zhan Wuya frowned and said. Hardcore tools require alloy steel materials, especially rare metals such as tungsten, cobalt, tantalum and niobium – things that have not yet been seen. And alloy steel tools have high requirements for metallurgy and processing, and the superhard tools on various machine tools now used by the Ministry of Machinery Industry completely rely on the old space-time products in stock, and only in the processing and cutting that are not very demanding, the carbon steel tools made by the machinery factory are used.

Zhan Wuya thought about it again and again: "This is indeed a reason, but the lathe depends on good tools." At the moment, it's not just a few chains. Before the mass production of clear qualified superhard tools, I can't rest assured that the tools will be consumed recklessly. I think we still start with the three links of tolerance control, forging and heat treatment. After cutting, another heat treatment is applied to relieve stress. ”

The discussion of specific processes and solutions continued until the early hours of the morning, and everyone dispersed after a supper.

Early the next morning, the chain was reopened, and after the chain blank was made, it was transported to the Bopu Arsenal, where it was forged on a large forging machine in the arsenal - the largest tonnage forging machine owned by the Crossing Group, where all the large equipment, heavy artillery and ship keels of the Crossing Group were forged.

After forging, the chain is transported back to the factory, where it is annealed in a heat treatment furnace and then machined. However, after cutting, a heat tempering treatment is applied again to eliminate the prestress generated during machining. Then normalizing and surface treatment are carried out. Zuihou is joined with a threaded buckle and assembled into a seamless chain buckle.

"Take it and put it to the test." Zhan Wuya looked at the finished chain, "Do a tensile test." ”

"I'll preside." Sun Li said.

"Okay, it's our own business to strictly control it, not to fool customers."

"Of course." Sun Li said, "Let's go, go to Shiyan Field"

A few naturalized mechanics who had been studying on the side answered, lifted their chains and walked out. The female apprentice handed Zhan Wuya a large enamel cup of tea and a towel. Zhan Wuya drank most of the cup in one go, and wiped his sweat again. Take care of the female apprentice and bring you a few bottles of salt soda.

"Two more packs of cigarettes"

Several veterans squatted at the door of the heat treatment workshop to smoke, waiting for the test results - no smoking is allowed in the workshop, this is the rule set by Zhan Wuya. The female apprentice hurriedly brought a few small benches. Although it was mainly done by naturalized migrant workers, several veterans supervised and guided almost every step of the way, and worked for two days and two nights. Everyone's eyes were red.

After a lot of effort, Sun Li came back with a smile: "The egg is successful"

Several people stood up at once, Zhan Wuya was a little excited, and asked again: "How is Shiyan?" ”

"The tensile test was done according to the actual working condition of the dumper, and it was completely passed. It doesn't break until it reaches 120%. Sun Li said, "I think we can do the whole machine test of the dumper right away."

"Okay, this time Shiyan started mass production by quickly compiling a process manual." Zhan Wuya is very excited, the mine chain is now an urgently needed product - large-scale mine development almost all use the mine chain. With the basis for the manufacture of high-strength mining chains, the chain production on many industrial equipment will be overcome in the future.

After the success of the second test, the General Machinery Factory made improvements to the bucket elevator. First of all, an anti-reversal device with a ratchet mechanism is installed. The bucket elevator is the most taboo power interruption, one side of the lifting process is the upward hopper full of materials, and the other side is the downward empty hopper of unloading materials. After the power is interrupted, the hoist will inevitably reverse due to gravity. The material is unloaded to the bottom of the bucket elevator with the hopper reversed until it is full and stuck. Since the reversal is an accelerated movement, it is easy to tear off the hopper and cause damage to the equipment.

Modern bucket elevators are hermetically sealed – the purpose is to reduce the amount of dust that flies during lifting and unloading. In order to save materials, the machinery factory designed the hoist at the beginning of the shell, but in the shiyan process, everyone thinks it is better to install it - anyway, an iron shell can not consume much material, but it can greatly reduce dust pollution. There is no way to solve the occupational disease caused by industrial dust. In addition, the dust of iron ore is also iron ore, which can be used to make steel when sintered.

However, there is a new problem with the iron shell, and it is found that after the sealing is sealed, there is a difficulty in feeding and discharging the hopper, and the hopper is not loaded and unloaded. Everyone hurried to the jishu archives to find the design drawings, and found that the workshop director of the sheet metal workshop responsible for manufacturing the sealed shell of the hoist was a certain veteran who saved trouble and omitted the suction pipe and vent at the head and bottom of the hoist.

The sealing shell is well-made and reliable, but the pressure difference between the unloading and feeding of the material is generated, and the negative pressure in the sealing shell is formed. Resulting in poor loading and unloading. The vent makes the internal pressure of the hoist basically equal to the external pressure, and the function of the air suction outlet is to avoid dust overflow from the vent through suction, avoid waste and clean the environment.

"Lesson, comrades, this is a profound lesson." It is inconvenient for Zhan Wuya to openly reprimand the patriarch, but he still can't help but beat this model at the work conference, "A design on industrial equipment, a process means, are the direct embodiment of the lessons accumulated in the industrial society for many years, not who wants to change can change this kind of non-rigorous attitude, in industrial production is going to have an accident."