"First of all, let me tell you about the single-rope winding hoist. ”

"This kind of hoist appeared earlier, and the mechanism is the simplest. Its working principle is: one end of the hoisting wire rope is fixed to the hoist drum, and the other end is connected with the hoisting container around the overhead wheel on the derrick. ”

"Taking advantage of the different winding directions of the wire rope on the two drums, when the hoist rotates, the two lifting containers are lifted up and lowered one by one to complete the lifting task. ”

Zhao Guoyang explained a few words, and Yuan Qinghua, a doctor from the Department of Fluid Mechanics, asked: "Mr. Zhao, after listening to your explanation, can we understand it like this?" ”

"The most critical point of this single-rope winding hoist is the material of the wire rope?"

"Well, you're right to understand it this way, but it's somewhat one-sided, the mine hoist, after all, is an organic whole, and it is difficult to separate its various parts. ”

Zhao Guoyang tapped his fingers on the table and said: "But there is one thing you are not wrong, the material of the wire rope is not up to standard, and it is indeed a major problem of our domestic mine hoist." ”

Hearing this, Yuan Qinghua nodded silently, and at the same time took out a pen and made some notes in the notebook.

Zhao Guoyang stared at him and continued to tell his story.

"The single-rope winding hoist is divided into single drum and double drum series. The core key is the spindle device, the rope adjustment clutch, and the reducer. ”

As the main working mechanism of the single-rope winding hoist, its role has the following points. ”

"The first is to wind the hoist wire rope, the second is to bear a variety of normal loads, including fixed loads and working loads, and the third is to bear the extraordinary loads caused by various positive conditions. ”

Although Zhao Guoyang's narration is not fancy, it is clearly organized and substantial, showing his solid basic knowledge.

Listening to his story, Li Zhaohe, who has been engaged in mining equipment for decades, couldn't help but secretly admire.

"Chairman, since the spindle device is so important for the single-rope winding hoist, its performance requirements should also be very high, right?"

Hearing the heart, Zhao Siyan couldn't help but ask.

Zhao Guoyang nodded approvingly and said, "Siyan, you asked very well." Indeed, on the hoist, the spindle device is a very important component. ”

"Some international mine hoist companies also have high requirements for this component. These enterprises require that the spindle device must not allow defective deformation under the action of extraordinary loads. ”

Hearing this, Liu Yan opened her voice angrily: "This requirement should not be difficult to meet." Wouldn't the problem be solved if the spindle unit was made of better materials?"

"That's true, but Liu, you have to know that the spindle material of this mine hoist is not the same as the spindle material of ordinary machine tools......

Liu Yanliu's eyebrows frowned slightly, and she said with some disdain: "Hmph, of course I know this." The commonly used material for shaft parts is No. 45 steel. ”

"For shafts with higher precision, 40Cr, bearing steel GCr15, spring steel 65Mn can also be used, and it is not uncommon to use ductile iron as shaft parts. ”

After Liu Yan finished speaking, she glanced at Zhao Guoyang with demonstrative eyes, meaning to tell him that Miss Ben was not a vegetarian.

Looking at the proud appearance of this brainy girl, Zhao Guoyang felt a little funny in his heart.

Liu Yan caught a glimpse of Zhao Guoyang's expression as if he was smiling, and his face was a little difficult to look at.

Obviously, she misunderstood that Zhao Guoyang was taking the opportunity to "examine" her proud figure.

Feeling the annoyance in Liu Yan's eyes, Zhao Guoyang hurriedly coughed to hide his gaze, and then slowly spoke.

"Liu is worthy of being a top student of the Department of Materials of Jingbei University, and his understanding of shaft materials is still very comprehensive, but ......"

"But what?"

Originally, after listening to Zhao Guoyang's first paragraph, Liu Yan was still a little complacent, but when he said the word "but", Liu Yan's face changed, and she couldn't help asking.

Zhao Guoyang put down the pen in his hand, put his hands together and said: "Liu seems to have ignored one point, the spindle device of our mine hoist, the spindle used, but it is high-speed and heavy-loaded, and the spindle of the general machine tool has an essential difference. ”

"This ......" Hearing this, Liu Yan's face turned red.

In the process of studying, her understanding of spindle materials was only limited to some machine tools and ordinary machinery, and there was no large construction machinery such as mine hoists.

Therefore, in the choice of materials, she made some mistakes that novices tend to make.

Zhao Guoyang did not mean to be sarcastic, he continued: "For the spindle in high-speed and heavy-load environments, we generally use low-carbon alloy steels such as 20CrMnTi, 20Mn2B, 20Cr or 38CrMoAL nitriding steel. ”

"Although these materials can be produced by domestic steel mills, there are very few of them that can be supplied in large quantities and have excellent quality......

When Zhao Guoyang said this, everyone in the conference room basically understood: the localization of the main shaft device of the mine hoist is probably the problem.

Seeing that everyone was silent, Zhao Guoyang smiled and said, "Of course, we don't have to be discouraged by this." ”

"As long as we try to optimize as much as possible when designing, and then communicate carefully with the steel mill to let them manufacture carefully, there is still a great opportunity for the localization of spindle devices. ”

After saying this, Zhao Guoyang picked up the teacup and took a sip of water, then turned his gaze to those students and said, "Do you have any questions about what I said just now?"

"If there is, it's best to bring it up now. Although we don't have a lot of time, it is still necessary to help you sort it out. ”

After Zhao Guoyang finished speaking, several students discussed in a low voice.

Seeing that his students were seriously discussing, Ji Chongxuan nodded with relief.

It didn't take long for the big man Kong Dezhong to speak first: "Mr. Zhao, there is a question, I wanted to ask it just now, but I never had the opportunity." ”

Zhao Guoyang was happy when he heard this, stretched out his hand and made a "please" gesture and said, "It's okay, classmate Kong, it's not too late for you to ask now!"

Kong Dezhong nodded, and explained his questions.

"Mr. Zhao, what I want to ask is about the difference between single drum and double drum of single rope winding hoist. Can you tell us more about the differences between the two, as well as their respective structural characteristics?"

When Zhao Guoyang heard this, he said: "Of course this is no problem, in fact, single reels and double reels are also called single cylindrical rollers and double cylindrical rollers in academics." ”

"For a single cylindrical drum, the structure is simpler. It is two wire ropes sharing a drum winding surface, the first wire rope is loosened from the drum, and the corresponding leakage of the drum surface, and then by the other wire rope winding. ”

"As for the double cylindrical drum, each of its wire ropes is wound around a unique drum, i.e. at any given moment, the wire rope is only wrapped around half of the total winding surface of the two drums. ”

"In this case, one drum is firmly fixed to the spindle, and the other can be looped on the spindle and connected to the spindle with the help of a clutch, so that if necessary, the two rollers can be rotated relative to each other at the same time......"

As soon as Zhao Guoyang's voice fell, Kong Dezhong opened his voice again: "Mr. Zhao, what is the use of the relative rotation of these two rollers?"

Zhao Guoyang raised his hand and said: "The relative rotation of the drum can make the operation of the hoist easier, because it can easily adjust the length of the wire rope due to the elastic deformation and gradually elongation." ”

In addition, the relative rotation of the two rollers can also compensate for the length of the cut off due to periodic tests on the wire rope. ”

Therefore, on the surface of each drum, in addition to the length of the wire rope to lift the height, a certain length of wire rope is also required. ”

"In this way, when the drum rotates relatively, the vertical length of one wire rope increases, and the length of the other wire rope does not decrease......

Zhao Guoyang's image narration did not mention too many conceptual things, and he completely answered Kong Dezhong's question, which made this guy can't help but be amazed.

Xu Linlin and Chen Li on the side were also secretly praised, even Yuan Qinghua, who had the highest education, also looked at Zhao Guoyang with admiration.

As for Liu Yan, although she still looks unwilling to admit defeat on the surface, in terms of the theoretical basis of the mine hoist, she is already convinced from the bottom of her heart.

Just when Zhao Guoyang was about to continue to tell you about the next important component of the hoist - the reducer, Tang Wanru, who had not been very noticeable, suddenly looked forward to Ai Ai's voice.

Zhao ...... Mr. Zhao, I have a question, I want you to help answer it!" Although Tang Wanru's voice was low, the firmness in her tone could be heard.

Zhao Guoyang's gaze froze slightly, and then naturally fell on the other party's body.

Looking at this girl with a flushed face, Zhao Guoyang smiled and said, "Classmate Wanru, please have something to say, I have already said it just now, today's meeting is to communicate and discuss together." ”

"So, you don't need to be inhibited!"

"What I want to ask is the material of the spindle device......

Tang Wan's words did not surprise Zhao Guoyang.

After all, she, like Liu Yan, is a top student in the material department, and it is not difficult to understand to ask more questions about materials.

Thinking about this, Zhao Guoyang bowed his head slightly and said, "Classmate Wanru, please ask!"

Tang Wanru nodded lightly and said softly: "I just listened to your words from Mr. Zhao, and we all have a relatively intuitive understanding of the importance of the spindle device. ”

"What I want to ask is that since the main shaft of the mine hoist has to bear all kinds of external loads, it acts on the base through the bearing. ”

"So in the process of production, the lifting container on the spindle is overloaded, and when it encounters emergency braking or other sudden conditions, the instantaneous load on the spindle may far exceed the usual rated load, right?"

"If this happens, isn't it likely that the spindle will have a safety problem?"