Zhu Hongsan knew that this was already five days later. Ma Xiaofang knew that she could not go out, so she asked her third brother Ma Jingyuan to inform her lover. After hearing Ma Jingyuan's full story, Zhu Hongsan laughed in her heart and asked, "Where is your eldest brother and second brother?"

Ma Jingyuan said: "My elder brother went back to HN the day before yesterday because of his busy business. My second brother was at home to review his books."

Ma Jingyuan thought for a while and said, "Sanwazi, I tell you, you should be kind to my sister in the future? After this incident, basically no one dared to come to propose marriage. I think it would be impossible not to marry you. If you are not good to my sister in the future, I will make you look good."

Zhu Hongsan knew some things about the Ma family and knew that Ma Jingyuan had a low presence in the Ma family. He didn't expect to be so good to his half-sister. Zhu Hongsan asked: "Ma Laosan, isn't your aunt bad to you? Why are you still protecting Xiaofang?"

Ma Jingyuan said, "You don't know that in our family, only my sister is sincere to me, and she treats me as her family. The aunt is indifferent to me. The eldest brother is too far away from home and doesn't have much contact with me. The second brother is a prodigy and is polite to me on the surface, but I know that in my heart, I treat me as my younger brother, and maybe it's better than the servants at home. Only my sister secretly sends steamed buns to me at night when I was punished by my father and refused to eat. So I won't let you go if you treat my sister in the future."

After Ma Jingyuan said that, he left. Looking at Ma Jingyuan's back, Zhu Hongsan thought: "It turns out that no one is really stupid. No matter who you are, as long as you are really kind to him, you will be rewarded."

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Time flies, and in the blink of an eye it is the seventh year of Chongzhen. The chaos in the world is a foregone conclusion. In the second year of Chongzhen, Li Zicheng finally had no choice but to join his uncle Gao Yingxiang. It was also this year that the murderous devil Zhang Xianzhong also uprised in Shaanxi and called himself the Eight Kings. Two heavyweight contestants of the peasant uprising at the end of the Ming Dynasty finally took the stage of history.

From the first year of Chongzhen to the third year, there were more than 100 peasant army troops in Shaanxi, and the peasant army had become a prairie fire. At this time, due to the corruption and incompetence of the generals of the official army, thousands of combat-capable border troops mutiny due to shortage of wages, and also joined the peasant army and became the backbone.

At this time, the peasant army was fighting spontaneously and blindly. The central government ordered the trilateral governor Yang He to adopt the strategy of "suppression and pacification, focusing on pacification". However, the central government was unable to support a large number of hungry people, and those who had already pacified the pacification rose again. Yang He was imprisoned for this.

At this time, a powerful man, Hong Chengchou, appeared. Chongzhen ordered him to supervise Shaanxi to change to the policy of "suppressing strong support, first suppressing and then pacifying" to concentrate his troops to attack the Shaanxi peasant army. The peasant army of various units advanced eastward. From the fourth to the sixth year of Chongzhen, the activity center moved to Shaanxi to fight from extreme dispersion, and each of them developed to relatively concentrated, echoing each other. Gao Yingxiang, Zhang Xianzhong, Li Zicheng, Luo Rucai and other troops had more than 200,000 people, known as the 36th Battalion, and once defeated the cities of Daning, Zezhou, Shouyang and other cities.

In the winter of the sixth year of Chongzhen, Gao Yingxiang and other 24th battalions broke through the siege of the official army, moved to the north of Chu in western Henan, and officially entered the hinterland of the Central Plains. The general trend of peasant uprisings had been established and could not be extinguished in three or five years. After entering the Central Plains, the peasant army took Yunyang as the center and interspersed between Henan, Chu, Sichuan and Shaanxi, using the weakness of the official army's division of troops to defend the territory, and the mutual disagreement was uncoordinated to carry out guerrilla mobile warfare. In order to change the passive situation of "different powers and waiting and watching each other", the central government changed to the policy of "concentrating troops and comprehensive encirclement and suppression".

In the seventh year of Chongzhen, Chen Qiyu was appointed as the governor of the five provinces, and unified the command of the official troops of Shaanxi, Shanxi, Henan, Sichuan and Huguang, and attacked from all sides, attempting to wipe out all the peasant troops in one fell swoop. The peasant troops successively moved into Hanzhong, and the encirclement and suppression failed. Chongzhen Zhu Youjian withdrew Chen Qiyu and appointed Hong Chengchou as the governor of the five provinces. When he mobilized the official troops into Shaanxi and reorganized the siege, except for Li Zicheng still insisting on moving to Shaanxi and Gansu, other troops were transferred again. Now it is June of the seventh year of Chongzhen. What is our protagonist Zhu Hongsan doing?

Zhu Hongsan is fifteen years old this year (the ancients were considered to be a void year). He finally had financial power the year before. His mother Zhao Chunhua has become older in recent years. In fact, her mother is not old, just 34 years old. However, under the medical conditions of the Ming Dynasty, the average life expectancy is just 35 years old, and 34 is already old. Zhao Chunhua has become increasingly ineffective in recent years. She found that her son had grown up, so she handed over all the financial power in the family to her son.

Zhu Hongsan bought a farm outside the city with 200 taels of silver, with five houses and five more built by himself. This place will become Zhu Hongsan's base camp. Tieniu's father passed away last year. Zhu Hongsan bought Tieniu's blacksmith shop. Now Tieniu is working for Zhu Hongsan and is working hard to make weapons designed by Zhu Hongsan in the farm.

At this time, Zhu Hongsan had built a small steel mill in later generations. In later generations, Zhu Hongsan had proved that steel can be refined with charcoal and pig iron products. The disadvantage is that it is difficult to grasp the proportion of the materials, so what kind of steel can be produced each time depends entirely on luck.

Zhu Hongsan decided to use a converter side blowing method to smelify iron. The converter side blowing method was used to add a certain proportion of cooked iron. The proportion was about 75% pig iron and 25% tear iron. In addition, a very small amount of sand and baking soda was needed, because China's iron ore was all pyrodite, and the steel produced in this way became brittle. The sand was used to cause acidic slag and absorb the phosphorus contained in pig iron. The baking soda was used to desulfurize.

After Zhu Hongsan discovered diatomaceous earth, he fired it into refractory bricks. He built an iron melting furnace in the farm. This round iron melting furnace is not big, but it is much more complicated than the converter. Because the converter requires that the iron and water coming out of the iron melting furnace must reach 1380 degrees Celsius. This temperature is difficult for ordinary fuels to reach. Before there is no heat storage chamber, the maximum temperature that can be reached by manual operation is 1250 degrees Celsius.

To reach this temperature, cold blowers must be replaced with hot blowers. This is the so-called "heat storage chamber". The concept of hot blowers was invented by the British Nelson and was applied to the iron factory in Glasgow in 1829.

The technical level of the heat storage chamber adopted by Zhu Hongsan is roughly the same as that of the British Steel Factory in 1850. It uses a cast iron tube hot air furnace. The cold air passes from the branch pipe on the main pipe of the blower pipe to each heating furnace, and passes through the arched cast iron pipe located on the fire and enters the pipe on the other side of the heat exchange chamber, and then enters the air outlet of the iron furnace.

The entire set of devices is sealed in an arched heating furnace made of bricks and refractory materials to preserve and reflect as much heat as possible. After the blower is directly heated, the temperature can be increased to 300 degrees Celsius, which is enough to melt lead. Another measure is to heat the exhaust gas, which uses ceramic pipes to lead the exhaust gas of the iron smelting furnace from the top of the iron smelting furnace, enters the heat storage furnace from the upper part, and then discharges from the exhaust gas port at the lower part.

Without a heat storage furnace, iron or steel can be crafted, but the production efficiency is completely incomparable. According to the calculations of the British, the early heat storage furnaces increased the air supply to more than 300 degrees Celsius, and the output of the same amount of fuel iron increased by three times compared to the cold blower.

The steelmaking furnace has basically been completed, and the next step is coking. Zhu Hongsan used charcoal in the early stage, but coking is still the most ideal fuel. Zhu Hongsan knew what to do with steelmaking. After all, his previous knowledge of metallurgy has not been lost, but coking is not possible, so Zhu Hongsan could only adopt a simple method of coking.

There are many methods of coking in soil. The simplest is the open-air method that accumulates. 2 to 4 tons of coal are piled into semicircles on the ground, with a diameter of 3 to 4 meters at the bottom and a straw that can cause fire. It can be coking in 4 to 5 days. The coking rate is only 50%. This method was used in the era of large-scale steelmaking, and the resource waste and environmental pollution caused is extremely serious. Now Zhu Hongsan, what else is concerned about environmental protection issues? It is important to save his life. Let’s talk about the others later.

After more than half a year of preparation and construction, the coke and pig iron were finally ready. Zhu Hongsan summoned the iron cow and some workers. He repeated several key points with the people in each operating position: First, the air volume must be adjusted evenly, and it cannot be too big or too small. Secondly, when the molten iron is poured into the furnace, it cannot be higher than the air outlet, otherwise the air outlet will be killed. Finally, the amount of molten iron should not exceed one-sixth of the converter furnace cavity at each time, and the workers are required to make good records, because without a thermometer, Zhu Hongsan has made plans to produce scrap steel in the first few furnaces.

Two livestock blowers began to operate at the same time, with two cows as power, and two on the side as a supplement. One blows the iron melting furnace to gradually increase the temperature to above 1300 degrees, and the pig iron ingot has been completely melted. At the same time, the converter is preheating. According to requirements, the entire converter must be preheated to 1000 degrees Celsius to reduce the temperature loss after the molten iron enters.

Since there is no thermometer, Zhu Hongsan can only go to the battlefield based on experience. At least when he was in an internship in a steel mill, his master taught him to judge the temperature by the flames. The molten iron was poured into the converter and began to be blown. The molten iron continued to heat up under the urging of high-temperature and hot air.

Zhu Hongsan stared at the flames in the furnace, and iron flowers were constantly emerging. The flames were red and yellow, followed by yellow-white, and finally completely white. This shows that the furnace temperature was constantly rising. The blowing lasted for about ten minutes, and the density of the star-shaped carbon flowers continued to increase, and the white and bright flames changed from short to long. At this time, the combustion of carbon reached its peak.

When Zhu Hongsan saw that the flames began to shorten and the carbon flowers became sparse, he knew that the remaining carbon fraction in the molten iron began to approach the steel content. He used the rocking furnace rod to rise and fall one or two times to see if more carbon flowers exploded. When he saw that the carbon flowers did not suddenly increase, he ordered to turn off the wind.

Then, the workers removed the furnace cover and air duct, started to slag and slag, and finally poured. The molded sand was made of 90% yellow sand, 5% clay and 5% white mud. After casting and forming, it was a steel ingot. As for the steel ingot, which is high-carbon, medium-carbon and low-carbon, it cannot be controlled now. It has to be judged by the professional blacksmith of Tienniu after cooling.

The first furnace produced about 30 tons of steel, which is the minimum amount of feed. According to Zhu Hongsanjian's blast furnace, a maximum of 260 tons of steel can be produced in one furnace. After the cooling just now, the iron giant took a look and beat it with a hammer. He ran over excitedly and said, "Brother, this pot is full of 100-strong steel."

The workers around were shocked when they heard this. For more than half a year, they thought it was just this fair young master who had made money from his family. The steel was made by making hundreds of exercises, but I never heard of it being able to be made directly with the stove.

Zhu Hongsan nodded and said to the foreman Lao Liu: "Uncle Liu, have you remembered all the process just now, especially the color of the fire, have you remembered it carefully?"

Old Liu's name is Liu Tiesheng. His family has been scrambled for generations. When he first came, he heard that he wanted to build a steel furnace. But after seeing it becoming a reality, he immediately changed his attitude towards Zhu Hongsan and actually held the etiquette of his disciples. He felt that this must be the secret of the little husband's family. Now he taught me, then I am his disciple. Old Liu said respectfully: "Master, I remember it."

Zhu Hongsan didn't care about Lao Liu's psychological changes. There were many things that were surprised in the future, so he went there. Zhu Hongsan nodded and said, "Okay, you can practice your hands first, and use the minimum amount of feeding."

Seeing Lao Liu leading someone to experiment, I didn’t mention it. I looked at the steel ingots I practiced, and looked at it. It was probably medium-carbon steel, which is the level of steel in later generations. But don’t forget that it is the Ming Dynasty, and I dare to report it. In China, no one can produce so many hundred-melting steel at once. But it’s still a small amount. A cannon costs 300 to 500 kilograms of steel. It seems that the current steel needs to be used in urgent need.

I found Tie Niu and asked, "How about using this steel to build your chain mail?"

Tieniu said: "Of course, a pair of chain mail weighs about fifty kilograms. Using this kind of 100-pound steelmaking can achieve the same protective force by only 30 kilograms."

Zhu Hongsan said: "I think the process of your chain mail is too complicated. I will improve your production process when you have time to increase the output."

Tie Niu Xi said: "Okay, this time I have steel, so many things can be made."

Zhu Hongsan stopped him and said, "Don't do anything else first. If you have time, you can use 100 gunpowder jars first, and you should have the thinnest one."

"Okay, I'll do it now."

After checking it out, I didn’t need anything to do. I told Lao Liu to pay attention to safety. At the same time, I told Zhao Tiedan to do a good job in security. Zhu Hongsan rode back to the city. I haven’t been home for the iron furnace smelting for half a month. I wonder what I was anxious about.

It was almost time to reach the city gate. Zhu Hongsan saw a shanty town, which was filled with hungry people from Henan. Because Li Zicheng and Henan had been destroyed, a large number of hungry people crossed the Yangtze River to Huguang. There were quite a few in Wuchang County, with about 10,000 people, and almost 50,000 people in the capital.
Chapter completed!