Traveling through the sword to engage in military industry

Jincheng.

Three days later, Ren Zhong received the analysis report that Professor Hu had worked on day and night. As expected, the high impurity content in the raw materials was the main reason, and the refining temperature was also slightly exceeded.

In terms of technology, Ren Zhong's super simple open-hearth furnace could not be adjusted for a precise refining process.

Professor Hu proposed a suggestion for refined management in terms of charging, especially removing sulfur and phosphorus additives, ensuring accurate and even distribution of materials. After all, it is an open-hearth furnace, not a converter. The distribution of raw materials has a great impact on the smelting temperature and impurity removal.

With the money in place, Professor Hu's service was also very attentive. After finding the problem, he also thoughtfully provided a new material weight ratio based on the raw material composition test results, and suggested regular sampling of the raw material composition to avoid changes in the incoming material composition affecting the furnace failure rate.

In terms of temperature, Professor Hu knew that there was little room for adjustment. He suggested purchasing an infrared thermometer to measure the temperature inside the furnace from the outside. Although the accuracy is much worse than modern steelmaking temperature control systems, it is at least more reliable than judging the temperature by eye based on experience.

Since this cannot be finely adjusted, the change in temperature can only be measured intensively after adjusting the gas valve to find a suitable gas supply.

A detailed report manual, with theory and operation, Ren Zhong likes such tool people. The hundreds of thousands he spent were not in vain.

After receiving the manual, as usual, it was converted into traditional Chinese characters and printed out. This matter is all set. Ren Zhong then gave Professor Hu a new task, which was to configure a ratio process for producing gray cast iron according to the material composition here.

According to the next planned arrangement, it is to start producing machine tool castings, and the raw material needed to produce machine tool castings is gray cast iron!

Gray cast iron refers to cast iron with flake graphite. Because the fracture surface is dark gray when broken, it is called gray cast iron. Due to its excellent properties, including casting performance, vibration damping performance, wear resistance, cutting performance, and low notch sensitivity, it has become the most widely used cast iron, accounting for more than 80% of the total cast iron production!

It is the best choice for manufacturing various frames and box castings! According to the tensile strength, gray cast iron is divided into 6 different models. According to the standard numbers of the main plane, they are HT100 / HT150 / HT200 / HT250 / HT300 / HT350. The larger the load and the better the airtightness, the higher the grade of gray cast iron is required.

If you want to make some advanced applications such as engine cylinders, you need at least HT200 or above, but for Ren Zhong's upcoming machine tool production in the Liangjian world, it is enough to reach HT150 level.

So the first customized product research and development task given to Professor Hu Rentao was to create HT150 gray cast iron.

In Yangcun, Xu Jiucheng, who was holding a pile of ore and scrap steel materials, was at a loss, and his eyes were already surrounded by deep dark circles.

Ren Zhong gave him the process flow design diagram and raw material ratio, and even various chemical reaction formulas to assist in explaining the principle of the entire open-hearth steelmaking method, which made Xu Jiucheng fascinated. According to his understanding, there was no problem with the first furnace of steelmaking.

Everything is in line with the above production process instructions. The current problem shows that the composition of the expected material is different from the theoretical composition. According to Xu Jiucheng's idea, there is no other way at present, and he can only start doing different preparation experiments to explore a new ratio.

However, with so many raw materials and auxiliary materials, it is extremely difficult to create a ratio that can achieve the ideal performance of steel. Among them, the metal materials include: molten iron (or pig iron blocks), scrap steel, ferroalloys, and direct reduced iron ore. Auxiliary non-metallic materials: slag-forming materials such as limestone, quicklime, oxidants, and coolants. To carry out this test plan with a change range of 0.5% in the content of each input, Xu Jiucheng felt that he could fill three sheets of Xuan paper and still not be able to finish writing!

He clearly knew that there was a problem, but he couldn't find a solution, which made Xu Jiucheng fall into deep doubt.

"Engineer Xu, Engineer Xu" Ren Zhong, who was holding the new formula and infrared thermometer, saw Xu Jiucheng sitting withered in front of the open-hearth furnace, a little lost, and couldn't help shouting a few times.

Xu Jiucheng raised his head and looked at Ren Zhong with some blankness in his eyes.

"Engineer Xu, haven't you rested well these days? Are you not used to Yangcun?" Looking at Xu Jiucheng's big black panda eyes, Ren Zhong was taken aback. He hadn't seen Xu Jiucheng much in the past two days. How could he be as miserable as an internet addict who had been working hard for three days and three nights? It was really a bit shocking.

"Boss Ren, it's not these," Xu Jiucheng responded weakly. "I am ashamed of Minister Zhang and the old folks in the base area. I clearly know the problem of steelmaking, but I can't think of a solution."

"Oh, is that so? Engineer Xu, don't worry too much. Let's open another furnace and try our new formula," Ren Zhong said lightly.

"Boss Ren has a new formula?" Xu Jiucheng didn't pay attention at first. When he reacted, Ren Zhong had already walked past him and began to direct the workers to prepare the raw materials for the new furnace. This time, three scales of large, medium, and small were used, especially for the auxiliary materials that were used in smaller quantities, a scale with a measurement accuracy of one-tenth of a tael, that is, 3 grams as a small scale, was used for weighing, and the batching was completed again in strict accordance with the ratio given by Professor Hu Rentao.

After igniting, heating, and sending in gas for about six or seven hours, different color spots began to appear on the infrared thermometer purchased for tens of thousands of yuan, and the temperature was displayed at the same time. When the thermometer showed that the temperature inside the furnace reached 1800 degrees, Ren Zhong began to turn the gas control valve to reduce the gas input. As the amount of gas input decreased, Ren Zhong stopped only after watching the rising temperature begin to stabilize back to 1800 degrees.

When the temperature of scrap steel, scrap iron, and iron ore reaches 1800 degrees, the strong heat energy will melt them, and some of the molten pig iron will begin to produce ferrous oxide. The manganese existing in the iron ore and scrap iron is oxidized by ferrous oxide to form slag. This is not over yet. Then, the auxiliary material limestone configured in the furnace begins to chemically react with impurities such as phosphorus and sulfur to generate calcium phosphate and calcium sulfide, which also become slag and precipitate; the originally excessive carbon atoms in the molten iron begin to be oxidized by the oxygen sent in to generate carbon monoxide, which emerges from the molten iron as if boiling. After such a complex chemical reaction in the furnace, the molten iron gradually becomes molten steel and flows out along the steel outlet.

The most ⊥ new ⊥ small ⊥ said ⊥ is ⊥ at ⊥ six ⊥ 9 ⊥ ⊥ book ⊥ ⊥ bar ⊥ ⊥ first ⊥ release!

Xu Jiucheng, who was nervously following Ren Zhong, saw the molten steel flowing out and couldn't wait to take a spoonful with a crucible and pour it into the steel bar mold next to him for preliminary testing of the physical properties of the steel, and then watched the red molten steel cool and spread into a thin piece of steel. Only then did he start pouring cold water on this steel sheet.

When it stopped emitting heat, Xu Jiucheng took out the still warm steel sheet from the mold. It was about fifty centimeters long, no more than a finger wide, and only two or three millimeters thick. Xu Jiucheng used force to pull it, and the steel sheet immediately bent like a bow, but there was no trace of fracture!

It's done!

Ren Zhong looked at Xu Jiucheng's experiment, and a smile bloomed like a flower welcoming spring!

As expected, it is a krypton gold work. With this quality, I am afraid that it has the yield strength of carbon spring steel.

Ren Zhong didn't know that the ratio given by Hu Rentao was not simple. It was optimized by Hu Rentao using their laboratory's super small machine through hundreds of billions of simulated smelting processes.

The second update, continue to ask for monthly tickets!