After such a long foreshadowing, it is almost logical for Zhang Zhenhua to choose to agree with Chang Haonan's suggestion.

"In that case, let's start talking about some specific technical aspects."

Chang Haonan sat back in his place.

Having experienced later generations, he knows very well that technology research and development is a two-way thing.

Although there must be a problem with the comprador idea that it is better to buy and buy than to rent, but on the other hand, users have invested money, and decision-makers have been under pressure, and if the R&D unit has not been able to let them receive positive feedback, it is normal for others to hesitate about independent research and development.

So whether it is for the 430 factory or for Chang Haonan, who is preparing to rub the 973 project, he has to hurry up and come up with something short.

It's a bit of a rush for quick success, but that's the way things go about doing projects.

This is also the rationality of the trade, industry and technology route, first do business, achieve a certain amount of primitive accumulation, seek survival, and then develop new technologies, new products, and sales, to find new profit growth points.

It's just that some people are engaged in it, and they only care about the primitive accumulation, and forget all the work and technology behind it.

But Chang Haonan obviously won't be such a person:

"Abrasive flow machining is just the beginning of the Seiko plan, but grinding has always been our shortcoming, so I think this technology should be able to solve your immediate needs, at least come up with some results, and first save the turbofan 9 project."

"So, Director Zhang, you can specifically talk about the various problems encountered in the process of localization, let's analyze and analyze which ones can be solved in a relatively short period of time, and first carry out key research, which can be regarded as giving some confidence to the higher-level departments and the aviation troops."

"As for those that can't be dealt with immediately, you can make a list first, and the same problems may also be encountered in the future turbofan 10 project, and we will take them as the key research and development direction of the Seiko plan in the order of easy and then difficult."

"In addition to deep holes and thin tubes, there are many problems in machining."

Zhang Zhenhua's complexion also softened a little:

"For example, the high-pressure turbine bearing of the engine adopts a floating ring sealing device, and the temperature of the bearing rises during use, which will lead to the coking of the lubricating oil remaining at the sealing ring, the floating ring is stuck, and the shaft body is rubbed, and the sealing effect declines quickly.

"But the manufacturing process of this floating ring is very demanding, it took us almost two years to create a qualified product, but now the production speed is also very low, and the first batch of installed Spey is just in the centralized overhaul period, and the output can not keep up with the consumption at all, and the opinions of the troops are very large."

As he spoke, he pulled out one of the sheets from the stack of materials he had brought, pointed to an inconspicuous ring-shaped part on it, and said:

"This is it."

"In addition, there is a cleats at the root of the fan high-pressure rotor blades of Spey MK202, which is similar to the two pins on the top of the R15 engine, which is used to fix with the tongue and groove, which is also a consumable part that is in great demand for the troops, and the cleats made by ourselves are easy to change the natural vibration frequency of the blades because of the roughness is not up to standard, and the resonance damage to the engine occurs close to the maximum speed of the blades, causing many pilots to dare not push the throttle valve when flying the leopard after the overhaul......"

“……”

I said more than a dozen in a row, all of which were problems that had plagued the 430 factory for a long time.

Imitation, especially in the absence of technical information, actually has a lot of unique troubles.

Especially when it comes to materials and processes.

It's not even a matter of technical ability.

Even in countries with a higher level of material science, it is difficult to achieve a 1:1 restoration of the finished product in hand alone.

The same goes for processing.

The British only transferred technology and equipment, and did not send people to teach them by hand like Mao Zi back then, so many places that needed experience had to be explored little by little.

Chang Haonan looked down at the large pile of drawings spread out in front of him, and quickly sorted out the order of priorities in his heart:

"As for the floating rings, rotor locks and bearing balls you mentioned, they are similar to the processing of pipelines and deep holes, and our new abrasive flow processing method can fully cope with it, but we need to replace the new abrasive formula and PLC control program, about this, you don't need to worry, you can send someone to the 410 factory for further study."

Zhang Zhenhua, who heard this answer, breathed a sigh of relief.

The problem that Chang Haonan said can be solved immediately happens to be the most fatal part.

Dozens of J-7s are in dire need of wearing parts, and these planes are the absolute main force of naval aviation at present.

Once there is a large-scale lying nest, it is a big thing to break the sky.

That's why the offer to buy another batch of used Spey MK202s would be considered above.

Now to meet the needs of this batch of aircraft overhaul and maintenance, for the 430 factory has won a turnaround.

But he soon showed a worried look again:

"Changgong, if these parts are ground with your new process, then the consumption of this soft abrasive should be very large, right?"

He also remembers the technical documents he had seen before, which stated that the service life of the abrasives ranged from 0.5 to 8 hours.

During the day, when watching the processing process on site, there were indeed discarded abrasives that continued to be discharged from the fixture, and the 410 factory even arranged a special worker to replenish the consumed abrasives.

"Hmm...... This one does. ”

Chang Haonan naturally has no need to hide anything in this regard:

"How long it lasts depends on the material of the workpiece to be machined, but in short, it must be replaced frequently, otherwise it will not achieve the desired effect."

"Then the cost of this abrasive ......"

Zhang Zhenhua stroked his hair a little embarrassed:

"I see that there is silicon carbide in the abrasive formula, which seems to be a very valuable thing, and I remember that our country still needs to import it."

There is no way, the 430 factory is really tight in terms of money, the turbofan 9 has not been built for a long time, and the turbojet 8 is only equipped on the H-6, and the amount is very small.

At this time, Chang Haonan understood what the other party was worried about:

"Director Zhang doesn't have to worry about this, the kind of silicon carbide that needs to be imported is electronic-grade semiconductor silicon carbide, and what we use in this abrasive is the most common silicon carbide for coatings and construction, which can be completely domestically produced, and the purchase price is less than 1,000 yuan per ton."

"Is that so?"

Zhang Zhenhua, who suddenly realized, was completely relieved.

"But, Director Zhang."

Chang Haonan picked up a pencil and lightly dotted on one of the drawings:

"I have some personal thoughts about the Turbofan 9."

"Speak!"

Zhang Zhenhua immediately opened the notebook in front of him-

This is Chang Haonan's personal thoughts.

It was the personal idea of the man who made the Turbojet 14 reborn.

Gotta take notes!

"The 603 Institute should be developing a deep improvement of the J-7, right?"

This matter should not be a secret in the aviation industry, but Chang Haonan still used a question sentence.

"That's right, the current J-7 is mainly used by the Navy, and the Air Force has invested a sum of money because the combat design is more complicated, hoping to get an improved model with better performance."

Zhang Zhenhua nodded, the connection between Factory 430 and Institute 603 is quite close, and they were originally the suppliers who provided power to Flying Leopard, so they naturally knew this:

"However, the 603 Institute hopes to use all-digital design on this project, and there is a shortage of talents in this area, so the progress is not very fast."

The speaker has no intention and the listener has the intention.

Yao Mengna, who had been sitting in the corner without speaking, suddenly had a light in her eyes, as if she had thought of something.

But no one had noticed her mind at this time.

Chang Haonan naturally knew what was going on with the J-7A, so he continued almost without thinking:

"The Air Force has higher requirements for ultra-low-altitude penetration in complex terrain, and although the Flying Leopard is a twin-engine aircraft, when flying at ultra-low altitude, even if it is only a single-engine stop, it is easy to have irreparable accidents."

"In this case, it is better to take this opportunity to completely solve some of the problems you just mentioned, and it can be regarded as eliminating some hidden dangers in flight safety."

Although in general, Spey MK202 has no potential for comprehensive optimization, but for a seemingly small defect, but directly affect the reliability and life, it is still not allowed to ignore.

And they're not cumbersome to modify, and they don't even affect the whole body.

In the previous life, many J-7 aircraft failed in ultra-low-altitude conditions, and the second-generation ejection seats equipped with poor performance eventually led to many first-class flight accidents.

Like the Y-8 with icy wings, it can be regarded as one of the difficulties in the history of the aviation industry.

The turbofan 9 model was originally gradually perfected in this accident.

(End of chapter)