Chapter 601 NSK Group, what happened
When he just heard about the cause of the failure, Wang Xibo’s first reaction was...
I didn’t quite believe it.
From the perspective of a helicopter designer, even if he is not a designer specifically responsible for the transmission system, this is really outrageous.
Because the shaft system support bearing can be said to be the most basic place in the entire transmission system of the helicopter, its status is similar to the main bearing of the turbofan engine that Chang Haonan has studied before.
It only broke down less than 40 minutes after takeoff?
This problem is so big that it doesn’t even sound real.
For this cooperation project, Bingfei Group has adopted almost the most stringent standards. All design contents must be blindly checked at least twice by different people.
Even if there are some small oversights, it is impossible for such a big mistake to happen.
It is impossible that when Eurocopter Group purchased bearings, it just happened to buy defective products, right?
No way?
Who would believe such a big company?
Furthermore, even if they know that they are going to be used in a harsh environment like the main reducer of a helicopter, where human life is at stake, the bearing supplier wouldn’t be so bold as to issue fake products, right?
Therefore, after a round of analysis, Wang Xibo felt that the opponent's ground crew might have misunderstood.
After all, the design of this transmission system is quite different from the original plan.
With such doubts, he followed Pierre and climbed to the halfway height of the maintenance frame.
Then...
“Holy shit, is this really true?”
The other party’s ground crew skills are indeed in place. In just a moment, the outermost shaft system has been supported. The bearings were removed.
And on its side surface, there is really a ferocious axial crack.
Wang Xibo had never seen this scene before, and he was so shocked that he directly spoke Chinese.
You must know that the NH90 is a 10-ton helicopter with a rotor diameter of 16.3 meters. The bearing set for the main reducer is as big as a plate and several centimeters thick. The material should also be G13Cr4Mo4Ni4V or higher. grade bearing steel.
Although the main optimization direction of this type of material should be hardness rather than strength, it would be too outrageous to directly tear off the surface reinforcement layer...
Pierre next to him He also looked shocked. After a while, he looked at Wang Xibo next to him with doubtful eyes.
Although he didn’t say anything, the meaning was obvious——
You need to explain this, right?
Although the latter was also stunned, he still forcibly calmed down and said as if he had everything under control:
"Mr. Pierre, the problem of this transmission system is The design plan is not just taken and installed directly on the helicopter. You have completely verified it before, so I think it is unlikely that there are flaws in the design itself that neither you nor I have discovered. "< br>
“As for the specific cause of the problem, I will communicate with the country immediately and solve it as soon as possible.”
This statement is quite emotional.
As a provider of entire transmission system solutions, we will definitely have to take the blame temporarily until the problem is fully understood.
However, Wang Xibo pulled Pierre onto the same chariot with him in just two words -
The technical solution we came up with is true, but you have also checked and failed before. Approved.
Immediately afterwards, he gave a statement that he would immediately start troubleshooting the problem.
In short, all possible places where the other party might cause trouble were blocked in advance.
In fact, by this time, Pierre had already passed the initial stage of fear.
Smart IQ has regained the high ground.
He also realized that Wang Xibo’s logic was correct.
In that plan, the only thing that made it feel a bit risky was that at the beginning, the design margin was only less than 5%.
It is almost equivalent to leaving no room for maneuver in the subsequent calculation process.
But no matter how much was left, the final calculation and verification process was passed smoothly.
Then you can only say that the design level is high, but not that the margin is too small.
Secondly, logically speaking, when implemented in the production and manufacturing process, standard parts such as bearings should have some redundancy compared to their nominal performance.
It shouldn’t have deteriorated like this so quickly.
Of course, there is a more important point.
If it is really a design problem, then of course Bingfei Group must bear the main responsibility, but as the project leader, he is certainly not free from the problem.
After this idea was formed, Pierre immediately ordered the ground crew to drag the aircraft back to the assembly workshop, and restricted the access of people in the nearby area on the grounds that confidentiality was required during the troubleshooting process.
In any case, we have to wait until the real cause of the failure is determined before taking a long-term approach.
Just like that, a few hours later, the news that the NH90 prototype malfunctioned and needed help from the Ice Flying Group to investigate in China was reported to Chang Haonan.
It wasn’t even a phone call, but Liu Hongbo ran directly from the capital to Shengjing with the design plan and described what happened.
"Uh...Mr. Chang, why do I feel like you...are not surprised at all?"
Liu Hongbo was actually very nervous at this time.
The main reason is that he is in China after all, and there is no online remote diagnosis technology these days. It is not easy to attribute it based on verbal descriptions and a few blurry photos. He was even ready to ask for leave from Beijing Hang University and fly to France to see the situation.
This time I came to Shengjing to seek advice before leaving.
However, Chang Haonan across the desk seemed to have no nervousness at all.
"Ah... no, I was so shocked that I couldn't speak for a moment."
Chang Haonan tried his best to pretend to be nervous, but at this time, he was heartbroken His true emotion was actually ecstasy, so his face showed an unbearable expression.
"Oh..."
Liu Hongbo looked at his junior brother and boss's facial muscles twitching continuously. Although it seemed unlikely, it was clearly because he wanted to laugh but was holding it back. Characteristics...
"Forget it, let's not mention this."
Chang Haonan also felt that if we continue to play again, he might be a gangster, so he quickly changed the topic to the technical level:
"If it is true as you said, after the plan is released Two rounds of blind reviews have been conducted before, and if Eurocopter Group has confirmed it after arriving there, it is basically impossible to have a problem with the design, otherwise it may cause the main reducer bearing set to crack, and it is not even a fault. Design flaws of this level of wear and tear should have been seen long ago."
The decisive judgment even made Liu Hongbo on the opposite side feel a little moved for no reason.
What is this?
This is trust!
Mr. Chang trusts him more than he trusts himself!
Of course, this is purely his own strategy.
Chang Haonan set up the trap himself, and of course he knew what was going on.
The reason why I didn’t tell Liu Hongbo the whole incident was because I didn’t trust him——
Of course I don't mean the technical level, but the performance level.
Yes, in Chang Haonan's plan, Liu Hongbo also needs to go on a business trip to France.
It’s not just about making sure everything is safe.
From the perspective of R&D specifications, after the fault is determined, Liu Hongbo, the person in charge of the design, also needs to sign.
“Mr. Chang, if it’s not a design problem, could it be a production problem?”
Liu Hongbo looked unconvinced:
“According to my observations during this period, Eurocopter’s level of manufacturing things is quite good. For example, our imported AS565 has many design flaws, but after dismantling it, After opening, the craftsmanship will definitely be excellent, and it will be higher than our current level."
"Eurocopter may not have any problems, but what about the suppliers? ”
Chang Haonan began to guide the possibilities in the preset direction.
But Liu Hongbo still felt it was a bit outrageous:
"It can't be that when Eurocopter Group purchased bearings, it just bought defective products, right?"
"..."
This question made Chang Haonan not know what to do for a moment. How to pick up.
If you are too sure, it seems like you are jumping to the top.
So he simply said:
"Anyway, this possibility cannot be ruled out. Before you fly to France, talk to Wang Xibo first and ask them to use these few days to check the performance of all the components of the main reducer. After you go there, Look at the results and report to me."
......
Since Chang Haonan said this, Liu Hongbo naturally chose to follow it.
Soon, his troubleshooting suggestions were sent to Eurocopter.
At the beginning, Pierre was quite disapproving.
"It's impossible for our marketing department to just buy defective products when purchasing bearings, right?"
He said to Wang Xibo:
"And before placing an order for purchase, according to regulations, It’s to test the performance of the samples, and it’s not just like going to the supermarket and buying them casually.”
Actually, as I said before, Wang Xibo himself didn’t quite believe it.
But this was an instruction from China after all, so he had no choice but to ask Pierre to urge the testing department to do it.
Quan is treating a dead horse as a living horse.
However, within a few days, the report of the complete destructive test conducted by the quality inspection office was placed in front of the two people.
The results showed that the batch model bearings they bought were about 10%-12% lower than their nominal data in terms of structural strength, surface hardness and other key properties.
The report also specifically mentioned that the samples sent for inspection this time are completely different from the samples sent for inspection before the purchase contract was issued, and cannot be regarded as the same model at all.
“……”
Seeing this result, Wang Xibo and Pierre felt numb immediately.
"NSK..."
The latter slapped the report with one hand:
"You are really brave enough..."
(End of this chapter)