Inside the first brick house.
“This is the basic principle and main advantages and disadvantages of submerged arc welding. The advantages are high efficiency, no arc light, large penetration depth, high welding quality, sufficient metallurgical reaction time between metal and flux, high strength, and fewer pores and welds. Defects such as cracks are very suitable for welding of high-strength pressure vessels and boilers. It is suitable for getting started and has a wide range of applications.”
The theoretical class of submerged arc welding operation training is in progress. Yu Hua holds the chalk in his right hand and writes the basic principles, advantages and disadvantages of submerged arc welding on the blackboard: "The main disadvantages are that the welding process is generally suitable for flat positions, and other parts require special measures. It ensures that the granular flux covers the welding surface without falling off. In addition, the arc and welding parts cannot be directly observed.”
A semi-automatic welding machine with an industrial aesthetic and a funnel device is placed in the center of the yard. This is the real protagonist today. It is worth more than a thousand dollars and quietly exudes the cutting-edge welding technology of the 1930s. Unique temperament.
Elegant.
There are many welding technologies that surpass the submerged arc welding process in history. However, in today's era of 1937, submerged arc welding is the most advanced and cutting-edge welding process. There is no one.
If it weren't for Johnson, an American businessman, he might not be able to buy this thing.
Two silver-white stainless steel plates are placed next to the submerged arc welding machine. Below is a group of welders sitting on small benches. All the welders have straight backs and bright eyes. They hold pencils in their right hands and constantly record what Yu Hua writes on the blackboard. knowledge points.
This group of welders is not the middle-aged group as imagined. On the contrary, the oldest among them is only 26 years old, the youngest is 20 years old, and the average age is about 23 years old, which is extremely young.
The most important thing is that these people have the average education level of upper primary school, and one of them even has a junior high school education.
Everyone paid full attention and listened carefully, showing no disrespect to Yu Hua as a teacher.
Although Yu Hua is young, his mature scientific researcher temperament overshadows everyone else.
"Did everyone remember it?" After carefully explaining the theoretical knowledge about submerged arc welding, Yu Hua asked everyone.
All the young welders nodded. As "highly educated people" during the Republic of China, with an average of advanced primary school education, their learning and understanding abilities far exceeded that of the old welders.
Old welders have rich experience, but their ability to accept new technologies is far less than that of young people.
To be honest, Yu Hua didn't know where Jin Yu found these highly educated welders. He originally thought it would be good to find a group of experienced welders. Before starting the class, he was prepared to be threatened by the other party selling their qualifications.
As a result, during class, these young welders were like good students, extremely well-behaved.
Everyone nodded and took note of it.
"These are the basic parameters of the saw102 submerged arc welding machine. The rated voltage is 380v, the welding current adjustment range is 60a-100a, the load duration is 20%, the power is 8kW, and it uses three-phase power supply..."
After receiving the answer, Yu Hua picked up the flux manual with his right hand and explained the basic parameters.
"The welding standards are: the shape and size of the weld conforms to the design requirements, the surface is smooth and neat, and defects such as pores, slag inclusions, cracks, incomplete penetration, and welding nodules must not appear inside. The operation process must comply with the machine usage specifications."
"The operation technology is divided into three categories, butt direct welding, butt ring welding, and fillet welding. The welding method is divided into two basic types, single-sided welding and double-sided welding. According to the thickness of the steel plate, it is subdivided into single layer Welding, multi-layer welding, single-layer welding is easy to understand, it can be welded in one time, multi-layer submerged arc welding is mainly for thicker steel plates, since it cannot be welded all at one time, multiple layers are used, the principle is similar to building a wall, each layer is guaranteed to be welded Transparent to avoid cracks, the weld joints are staggered and cannot overlap. This is the schematic diagram of multi-layer welding..."
The theoretical class of submerged arc welding operation training was very successful. The reason why he took the theoretical class instead of going directly to the practical part was because Yu Hua wanted these young welders to 'know what is happening and why'. From a theoretical perspective Only by understanding the basic principles and operating procedures can you improve the upper limit of your welding skills.
Submerged arc welding is easy to get started with but difficult to master.
Gu Tu
The Eight-Road Organization behind Lin Wan wanted to mass-produce Yu's Seven Towers and build a sulfuric acid industry, which could not do without the support of submerged arc welding technology, let alone a group of welders who mastered qualified submerged arc welding technology.
In fact, if Yu Hua's guess is correct, the group of welders with advanced primary school education in front of him are most likely members sent by the organization.
Seeing through but not revealing, Lin Wan did not take the initiative to expose her identity, and he would not take the initiative to expose it.
Sometimes, people don’t cherish things that are easily obtained.
To fully demonstrate your own value, appropriate restraint is necessary.
Life is like a play, it all depends on acting skills.
At the entrance of the courtyard.
A gap was revealed in the lightly closed door. A man who had recently visited Liu Village stood at the door. He looked quietly at the scene in the yard. He was dressed simply and neatly, with sharp eyebrows and starry eyes, and a pair of dark and bright eyes that seemed to contain something. The stars exude an air of elegance.
The theoretical class in the yard has been completed. As a teacher, Yu Hua motioned for a student to come on stage, and then personally demonstrated how to operate the semi-automatic submerged arc welding machine and lay the flux and other preparations. This is the actual operation part.
When everything was ready for the practical operation, Yu Hua controlled the welding gun and welded two stainless steel plates with skillful and natural skills in front of everyone. The speed was not fast, just for demonstration.
The dazzling arc light of the past disappeared, replaced by a bright red and hot weld like magma. The metal in the weld continued to flow under the influence of high temperature, fully reacting, and achieving atomic level bonding.
Not long after, the two stainless steel plates were welded.
After the demonstration in person, Yu Hua once again found two stainless steel plates and signaled the students to operate. The first submerged arc welding student had a serious face, took the welding gun with both hands, and started welding under Yu Hua's careful guidance.
The working sound of the semi-automatic submerged arc welding machine is constantly heard, complementing the sound coming from the diesel generator set, playing an industrial hymn.
Time passed, and under Yu Hua's careful guidance, the first student successfully completed the welding. After inspection, the welding seam met the standards and the surface was smooth and clean.
"Theory and practice go hand in hand. This class was very good. It can be seen that Student Yu's knowledge level is very high." The elegant man looked at the students in the yard who had successfully mastered the submerged arc welding process and nodded gently, his eyes full of joy. He commented with admiration.
"Classmate Yu has always been like this. What he advocates most is 'knowing what is happening and knowing why it is the case'. Only in this way can the welders understand everything thoroughly. Even I have to admire Classmate Yu's high moral character." As a member of the Northern Department Liu Wei, the most responsible person, was standing aside at the moment, with a hint of respect in his posture, and said to the elegant man.
The elegant man heard this and nodded. He gently closed the door with his right hand, signaling to keep quiet and not to disturb the class. He pointed to the big locust tree not far away.
Liu Wei understood and left quietly. The two of them walked towards the big locust tree in the village.
When the sun set in the west, the sky was filled with red clouds, and the afterglow fell on the two of them.
"I came here this time, firstly for the situation in the north, secondly for the Seven Pagodas of the Yu Family, and thirdly for my classmate Yu Hua. Of course, there is another surprise now, the high yield of wheat. It seems that God is really blessing us. I didn't expect that I As soon as I arrived in Liu Village, there was such great good news waiting for me."
The elegant man's steps were steady and powerful. He looked at the sunset in the distance and said with a smile: "Old Liu, how is the progress of Yu's Seven Pagodas?"
"Thanks to the R&D team founded by Yu Hua, the research and development of Yu's Seven Towers is progressing quite smoothly. The design drawings have been completed. The design phase is basically over. Now it is the manufacturing stage. As you can see, Yu Hua is taking a submerged arc welding theory class and training. Submerged arc welding students, used to manufacture core containers." Liu Wei looked serious and reported on the recent situation of Yu's Seven Pagodas.
