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Chapter 158 Phoenix Factory Asks for Help

there is a problem.

The sound of "bang" is clearly audible!

Yang Wenjie's heart skipped a beat for no reason, and he quickly looked at the five-axis CNC machining center with an unmistakably nervous expression on his face.

Wang Qiang was also surprised, and immediately said: "Gong Yang, the knife may have fallen off."

"Stop quickly and take a look at the specific situation."

Wang Qiang stopped the machine tool, and then opened the safety door, and the situation became clearer. The milling cutter at work had collapsed, leaving only half of it on the cutter head, and there was an obvious small pit on the test piece.

Ugh.
How could there be a broken knife?

Yang Wenjie didn't understand, he kept sighing and shaking his head, holding the half-broken milling cutter for a long time.

"Mr. Yang, what should we do next?"

Yang Wenjie had no choice but to say, "Change to a new milling cutter and continue processing."

Wang Qiang did so, unloaded the remaining half of the milling cutter from the cutter head, installed a new milling cutter, re-calibrated the cutter, and continued processing.
Hexi factory.

Lin Feng was wearing a helmet, followed by Wang Yalong, and Ruan Xiangming, the construction manager here, inspecting the construction site.

Ruan Xiangming introduced the situation here, "Mr. Lin, the design and R&D building and the office building are already driving piles, and some pile foundation holes have reached a depth of 20 meters, and the No. [-] manufacturing plant has also started pile foundation holes."

While watching the situation here, Lin Feng listened to Ruan Xiangming's introduction, and exhorted, "Safety first, quality first."

"Rest assured, we will keep these requests in mind."

After inspecting, Lin Feng left satisfied. This is the third time he has come to inspect the progress of the construction after the Spring Festival. Basically, he will come to have a look every two or three days.

After returning from the Hexi factory area under construction, Lin Feng sat in the office and began to compile the design technical outline of the turboshaft engine himself.

Lin Feng has become more and more clear about what his first turboshaft engine looks like. It is positioned as the third-generation turboshaft engine. The output power of a single unit is 1500 kilowatts, the power-to-weight ratio is above 5, and the service life of the first overhaul is more than 3000 hours, etc. .

Lin Feng was writing the technical outline of the design himself, and sometimes he would stop to think about it carefully, while in the 406 workshop, Jiang Haitao was getting angry.

"What's the matter, I can't even do a test piece well."

Next to the CNC machining, Yang Wenjie, Wang Qiang and others lowered their heads slightly. They completely messed up the matter.

During the process of processing the test piece, the tool collapsed first, which is fine. The processed test piece was seriously unqualified, and several key dimensions were seriously out of tolerance.

Jiang Haitao's tone was very severe, "Whether you can still process this part, Mr. Wang is waiting for our news."

Yang Wenjie lowered his head and said in a low voice, "Director Jiang, the processing of this part is too complicated, and we are not fully sure."

Maybe he also knew the difficulty of processing. After Jiang Haitao criticized a few words, his tone gradually softened.

"Then what should I do, or I'll give you two more days to re-check the NC program and find out where the problem is."

Yang Wenjie has a big head, and with their level, it is really difficult to write such a complicated CNC program. After hesitating for a while, he suggested, "Director Jiang, this is really too complicated, or please ask my master to come over and help me." .”

His master is Lin Feng.

After learning programming from Lin Feng for a period of time, he also signed a master-apprentice contract, and Lin Feng was indeed his master.

Facing this proposal, Jiang Haitao did not answer, sighed softly, and left.

He had to report this matter to Mr. Wang.

In Wang Tianfang's office.

Zhong Jianming came over again, besides him, there was Yang Dexing, the chief designer below.

"Mr. Wang, how is the processing of our two centrifugal impellers going?"

Wang Tianfang said, "The first thing to process is the test piece. At this time, the processing of the test piece should have been completed, and we are ready to start the formal processing of the first centrifugal impeller."

Zhong Jianming suggested, "Take us to the manufacturing site now to see how the processing is going."

Wang Tianfang thought for a while, he didn't have any important business this morning, so he got up and said, "Okay, then let's take a look together."

The three walked out of the office and walked towards the 406 frame.

Yang Dexing said: "Boss Wang, these two centrifugal impellers are very important to us, please ensure the quality."

Wang Tianfang nodded slightly.

It didn't take long for the three of them to walk into the production site of workshop 406, and soon arrived at the side of this CNC five-axis machine.

Jiang Haitao, Yang Wenjie, Wang Qiang and others were all beside the machine tool. Wang Tianfang asked, "Director Jiang, how is the processing of the test piece?"

Jiang Haitao sighed, and could only say helplessly, "Mr. Wang, we messed up the matter, and the processing of the test piece was seriously unqualified. Maybe it's because there is a big problem with the NC program."

what!
Things are screwed up! ! !

Wang Tianfang's face changed slightly, he picked up the test piece checklist on the table and looked at it, and then his face became a little ugly.

Shame on me!

The head model engineer of the Phoenix Institute personally came and commissioned the processing of two centrifugal impellers. He originally thought that the problem was not serious, but he didn't know that such a situation would occur.

"What did you do!"

Wuyou felt a little bit angry in his heart, hating that iron can't be made into steel!

Jiang Haitao's face was hot, and he said in a low voice, "Mr. Wang, the blade shape of this centrifugal impeller is very complicated, and the precision requirements are very high. It is very difficult for our technicians to be competent in the compilation of such a complicated numerical control program."

Now there is no NC programming software, no CAD, UG, etc. The NC program needs to be written line by line by technicians, and the milling of such complex leaf shapes also involves complex calculations.

Before Wuyou said anything, Yang Dexing next to him seemed a little anxious, "Then what should we do, we are waiting for design verification."

Zhong Jianming also suggested, "Mr. Wang, why don't you invite someone with a better technical level to write the CNC machining program."

Wang Tianfang looked at Jiang Haitao.

Jiang Haitao hesitated for a moment, and then said, "It seems that I can only ask Director Lin for help, and ask him to come and help me write this CNC machining program."

Just playing the piano!

He is such a big factory manager with so many things in his hands, how could he give us the job of a technician.

Wang Tianfang had a calm face, a little gloomy.

Zhong Jianming obviously didn't know Lin Feng, so he asked curiously, "Who is the director of Lin, please help him."

Wang Tianfang smiled bitterly, and explained, "Director Lin used to be a technician in workshop 406, and he contracted the equipment branch last year."

He briefly explained Lin Feng's situation.

Immediately, Zhong Jianming's eyes widened, "There is such a talented person. I am very interested in getting to know him. If there is really no way, I think it is okay to ask him to help."

There is really no way, that's the only way.

Obviously, Yang Wenjie and others were not capable of such complicated processing, so Wang Tianfang could only helplessly say, "Then ask Factory Manager Lin to help, and bring the design drawings, Xiao Yang, you all follow me there."

A group of people arrived at the equipment branch in this way. Everyone was lucky, Lin Feng happened to be in the office.

In the past two days, the focus of Lin Feng's work was to write the design technical outline of his turboshaft engine. The first draft was basically completed, and he only needed to consider and revise it.

"Xiaolin, we're here for help."

Wuyou let go of the point and said directly that he came here to ask for help.

Seeing such a large group of people, Lin Feng stood up and said enthusiastically, "Mr. Wang, if you ask for help or not, as long as I can help, I will help without hesitation."

"I like your attitude." Wang Tianfang smiled happily, and then introduced, "This is Zhong Jianming, the chief designer of Phoenix Institute, and this is Yang Dexing, the chief designer."

There was a warm handshake between the two parties, and a few polite greetings.

Soon, Lin Feng knew the purpose of everyone's visit. It turned out that Phoenix Institute designed a centrifugal impeller, and planned to process and manufacture two pieces for design verification.

"Can I have a look at the design drawings first?"

"Of course no problem."

The design drawings were spread out on the big table, Lin Feng looked at them carefully, everyone kept quiet and waited patiently.

The time passed by minute by minute, and after watching for three to five minutes, Lin Feng frowned slightly.

"Master Zhong, this is the centrifugal impeller you designed."

Zhong Jianming said, "We designed and developed this centrifugal impeller on the basis of absorbing the eight centrifugal impellers of the turboshaft, and prepared to use it as the centrifugal impeller of the future 1000-kilowatt turboshaft engine."

Lin Feng reminded, "I saw your design, and I think there are some problems that need to be improved."

what!
Is there something wrong with our centrifugal impeller design?
Zhong Jianming was slightly startled, and Yang Dexing was even more unconvinced.

To be precise, this centrifugal impeller was designed by Yang Dexing and his technical team, and he is very satisfied.

Who knew that Lin Feng actually said there was a problem.

Yang Dexing said, "Impossible, absolutely impossible. After our detailed calculations, there won't be any problems."

Lin Feng reminded: "There is no major problem, but its compression ratio is obviously low. It should be only a few points, and it may reach [-]. In addition, the surge margin is also a little bit small, and the blade shape design is too complicated. It will bring great difficulty to processing."

The centrifugal impeller is an important part of the compressor unit of the turboshaft engine. Its function is to further compress the air entering the engine. The compression ratio of the centrifugal impeller with excellent performance is generally above three, and can even reach [-].

A high compression ratio represents high efficiency and is an important data to balance the performance of the centrifugal compressor.

The surge margin is related to safety performance. High-speed compression has the risk of surge, and the designer must increase the surge margin to avoid this risk.

In order to reduce the difficulty of processing, of course, under the premise of ensuring the performance, the blade shape should be simplified as much as possible, rather than the fancy design.

Zhong Jianming was thoughtful, thinking in his heart, could this really be the case.

Yang Dexing didn't believe it at all, and his voice was raised twice, "You are talking nonsense, the centrifugal impeller we designed has no problems at all as you said."

Lin Feng didn't argue anymore, the problem has been pointed out to you, believe it or not.

Isn't it necessary to conduct design verification? You will know when the centrifugal impeller is manufactured and the design verification is carried out.

Lin Feng no longer struggled with this issue, changed the subject, and asked, "Xiao Yang, show me the NC program you compiled."

The prepared NC programs usually have a paper version. Yang Wenjie also brought it over and said modestly, "Master, please help me to see where there are problems."

Lin Feng nodded, took the paper version of the NC program and read it, and took a pen to modify several places, some of which were greatly modified.

"After I modified it, there should be no big problem with the NC program, but this milling cutter doesn't work, and a new milling cutter needs to be redesigned."

After speaking, Lin Feng took a blank piece of paper and drew a design sketch of the new milling cutter, and marked the main dimensions.

Yang Wenjie had a look of admiration, as expected of Brother Lin!

There was indeed a problem with this milling cutter. The cutter broke during the process of processing the test piece, and Lin Feng could tell at a glance that it was not suitable.

After the NC program was changed, Lin Feng found out the faulty milling cutter.

On behalf of Phoenix Factory, Wang Tianfang expressed his thanks in person, "Director Lin, thank you so much."

Zhong Jianming also said, "Director Lin, I didn't expect your CNC programming to be so good. I'll visit you again when the two centrifugal impellers are finished."

Lin Feng looked modest, "It's a trivial matter, so there shouldn't be any problem. I also have too many things at hand. Otherwise, it would be no problem to go to the 406 workshop to guide the processing."

Wang Tianfang said with concern, "Busy on the construction of the Hexi factory."

"Well, the construction of the Hexi factory area is the key point, as well as the manufacture of CNC broaching machines, and the preparation of the technical outline for turboshaft engines. There are many things to do."

"Director Lin, you are really planning to develop a turboshaft engine."

"Of course, I plan to use the turboshaft engine as an entry point to design and develop a turboshaft engine with high power and high power-to-weight ratio."

Listening to the conversation between Lin Feng and Wang Tianfang, Zhong Jianming, who was about to walk away, stopped and said in surprise, "Director Lin, you are planning to develop turboshaft engines."

He is engaged in turboshaft engines, and he is already doing some designs on the basis of digesting and absorbing the technology of turboshaft eight engines, and has also begun to do some design verification.

He was really surprised!

I never thought that there are still people in China who are engaged in turboshaft engines like them!
Lin Feng said modestly, "We are just an attempt, if we can succeed."

Zhong Jianming's friendship became even stronger, "Director Lin, then I must come to visit you some other day."

"Master Zhong is polite, what visit are you talking about, let's communicate more."

Lin Feng escorted them to the door and watched them leave.

Yang Dexing didn't speak all the time, and after walking away, he said with a little disdain, "Director Lin is too young, and he really doesn't know the heights of the sky and the earth, and he actually wants to make a turboshaft engine."

Yang Dexing has a deep understanding of the difficulty, which is not something that can be easily solved.

Zhong Jianming didn't think so, and reminded, "How can you say that, even if you don't succeed, people have enthusiasm, and this kind of spirit is very valuable."

Yang Wenjie, Jiang Haitao and others went straight back to Workshop 406.

According to Lin Feng's modified program, they overwrote the original program in the machine tool, manufactured new milling cutters quickly, and made a new test piece.

It took one and a half days to process the test piece, and the whole process was very smooth, without any pause, and the processing was completed in one go.

There is no problem with the visual inspection and dimensional inspection, so the formal processing of the centrifugal impeller begins.

Another day and a half later, the first centrifugal impeller was finished.

After the inspection, no matter the appearance or size, including the blade shape data, all were qualified, and the first centrifugal impeller was quickly taken away by Phoenix.

They rush to design validation.

After the centrifugal impeller arrived at the Phoenix Institute, it entered the laboratory immediately, and first did a dynamic balance, and then started the compression ratio test.

As expected of a design institute, the instruments and equipment are relatively complete, and the compression ratio test equipment is the most advanced in China.

The results came out quickly.

However, both Zhong Jianming and Yang Dexing couldn't believe the test data at all. The compression ratio was only 2.1, which was much lower than their expectations.

"Do it again, there must be something wrong with the experiment." Yang Dexing refused to accept such a result, and directed loudly.

The second test started again immediately, and soon after, the test data came out again, and the compression ratio was still only 2.1
If the results of the two tests are the same, then it is not a problem with the test process, but a problem with the design, the compression ratio is really only so much.

We all know that when air enters an aero engine, it must first be compressed, and the same is true for turboshaft engines. First, it will be compressed by the axial flow impeller, and then by the centrifugal impeller. The air compression ratio will generally reach more than ten. For turbofan engines, air compression The ratio is higher, often more than [-], and the turbofan engine with excellent performance, after the air is compressed by the compressor, the compression ratio will be more than [-].

Actually only 2.1.

This is really unacceptable, really shocking enough.

Zhong Jianming said, "The compression ratio should be 2.1, let's do the surge margin test.

The model engineer spoke, and the testers started the surge margin test, and then the test results came out.

The surge margin is very narrow, which means that the safety of the centrifugal impeller is very low, and surge is very easy to occur during work.

Zhong Jianming couldn't help but think of what Lin Feng said, and said in his heart with admiration, Director Lin is amazing, he has already seen where the problem is.

In addition to admiration, he also looked at Yang Dexing with dissatisfaction, "Director Yang, it seems that you have not fully digested and absorbed the technology of the turboshaft eight engines."

Yang Dexing's face was hot and he was very embarrassed.

No shame!

In front of so many people, Mr. Zhong actually said that.

"Redesign, the compression ratio must be above 3.0, and the surge margin must be increased by at least an order of magnitude."

After explaining a word, Zhong Jianming left the laboratory, thinking in his heart, should he sit with Director Lin and pay a visit.

After this idea popped up in his heart, Zhong Jianming looked at the time and thought that it should be fine now, and hoped that Director Lin would be in the office.

　Many book friends suggested changing the title of the book. At your request, the title of the book was changed to the current title.

　　
　
(End of this chapter)