Chapter 512: Finally able to independently produce turbofans!

Although it is just an improved model, aviation safety is extremely important, and the necessary testing procedures must not be sloppy.

What's more, the utilization rate of new technology in this so-called "Spei reform" is almost more than one-third——

The first prototype No. 9A-01 modified some unreasonable designs of the high-pressure compressor blades and oil supply parts, replaced it with a new domestic oil pump, bearings and gear sets, and integrated the original bearing components.

This reduces the number of components and widens the surge margin.

By this time, although there were still many modifications, they were still minor repairs to the prototype engine.

Not only the performance calibration has not changed, but the core design of the hot end component has also remained original, so the basic performance has not changed much, except that the weight has been reduced by about 75 kilograms.

But on the second prototype No. 1997A-9, which was produced at the end of 02, the changes were relatively large.

In order to test the effectiveness of the new active cooling technology, Chang Haonan specifically asked technicians from the 606 Institute to modify the engine performance calibration.

By improving combustion efficiency and upgrading aviation fuel, the temperature in front of the turbine has been increased by about 50-60°C, reaching a level close to that of the third-generation turbofan engine.

The design of aeroengine affects the whole body.

To this end, the compressor of the second prototype engine was also modified. The blade separation flow active control technology developed during the development of turbofan 9 was used on the 12-10-stage high-pressure compressor blades to reduce the total pressure of the compressor. The ratio increased to around 22-23.

However, because the research and development of the manufacturing process will take time, the electrolytic machining, electron beam welding, precision forging, precision casting and other technologies used in the production and manufacturing of this engine are still at the previous level.

Especially the processing of air film holes on the inner walls of turbines and combustion chambers.

Compared with dozens of accurate round holes, the dustpan-shaped holes with forward inclination developed by Chang Haonan are quite unfriendly to the EDM technology developed by Factory 410.

Not only does the processing of each hole require several more processes than the turbojet 14, but the subsequent grinding and quality inspection also require additional steps.

The yield rate is still much lower.

In short, although Chang Haonan could not wait to start testing this engine that uses a lot of turbofan 10 technology the day after posting the picture, even if the 410 factory specially set aside a production line and carried out production in three shifts 24 hours a day, it would still be It took more than two months to produce the 9A-02 machine.

……

At the entrance of the engine assembly workshop of the 410 Factory, Chang Haonan, Zhong Shihong, and Zhang Zhenhua stood side by side, watching the engine that had finally completed the factory's complete machine inspection be slowly installed on the specially designed engine bracket.

Zhang Zhenhua deliberately took two steps forward, reached out and patted the tail nozzle of the engine twice in mid-air.

Shengjing, mid-January morning.

The temperature is about minus 20c.

The metal tail nozzle was bone-chilling, freezing Zhang Zhenhua, who was not mentally prepared.

However, he still couldn't help it and gently stroked the exposed fuel oil pipeline on the outside of the engine casing.

Shen Zui's expression is slightly abnormal.

It wasn't until the engine was fixed by the hoisting team and started to be packed in cargo boxes that he reluctantly returned.

"Sibei, after more than 100 years of domestic production, we have finally created an engine that is % domestically produced..."

With bursts of white mist rising in front of him, Zhang Zhenhua said with emotion.

In order to speed up production, about a quarter of the components of the previous 9A-01 machine were directly assembled using parts imported from the UK.

But for this second prototype, due to the huge improvements in all aspects, the original British parts could no longer adapt to its working condition.

Therefore, all components are newly produced in the country.

During this process, Factory 410 also verified the application of several key new manufacturing technologies such as metal spraying, vacuum heat treatment, trajectory welding, vacuum brazing, and CNC pipe bending, laying the foundation for the next step of manufacturing the turbofan 10.

"Yeah, but it's a pity that it's a little too late..."

Zhong Shihong took out his ballpoint pen and signed his name on the factory order while responding:

"After the introduction of SPEI, there was a period of vacillation for more than ten years. Now that we have made domestic models, even if the performance is better than the original products, the prospects are relatively limited..."

The introduction of Sibei also hides a love-hate relationship between the 410 factory and the 430 factory.

The former insisted on continuing to develop turbofan 6, while the latter believed that it should start with Spey.

If anything, it was a lose-lose situation in the end.

As of now, it is no longer clear who is who.

Fortunately, for people of Zhong Shihong and Zhang Zhenhua's generation, they don't have many related memories.

The smell of gunpowder between the two units has gradually disappeared with the advancement of the turbofan 10 project and the deepening of R&D collaboration.

Contradictions fundamentally come from competition in resource allocation.

Now that Chang Haonan has almost increased the scale of China's aerospace industry by an order of magnitude, the difficulty of dividing the cake has naturally been reduced a lot.

Despite this, after noticing that the topic between the two people was gradually moving towards the past, he quickly changed the subject:

"It's useless to talk about the past."

While Chang Haonan was speaking, he also took the pen from Zhong Shihong and signed his name.

The production of the Turbofan 9A prototype is nominally as a technical verification machine for the Turbofan 10, so naturally the signature of his chief designer is indispensable.

"No matter what, there must be a demand for dozens or hundreds of improved JH-7s, and the turbofan 9A can still make a difference in this regard."

"It's just a pity that Spey Air changed to combustion. Now the QC14, which has been converted from turbojet 130 to combustion, has entered the design finalization stage. The Navy will probably not accept another gas turbine with similar power..."

After the factory procedures were signed, the staff quickly loaded the neatly packed engine packaging box onto a special Mercedes-Benz semi-trailer.

This car may be the only 10% original imported product in the entire Turbofan 100 project.

The main reason is that everyone is really busy and has no time to build a special engine transport vehicle.

The finished engine will be transported by this vehicle to Beiling Airport, and then transported by an IL-76 transport aircraft to 624 for necessary ground testing.

"Mr. Chang, what do you think the actual performance of this engine can be?"

As the director of the production department, Zhang Zhenhua has little experience in the field of engine design, so he does not know the specific effects of these upgrades on the Turbofan 9A.

"Don't have too high expectations..."

Chang Haonan shook his head, returned the pen in his hand to Zhong Shihong, and continued to explain:

"The design level of the Spey engine itself is not good. I spent a lot of time adjusting the data of the compressor and combustion chamber, but the matching degree is always average."

"After all, it is an improved model. It is impossible to go to great lengths to redesign a core machine. We can only make do with it this way."

There was some dissatisfaction with the British in his words.

Of course, the two people next to him wouldn't have any objections.

After all, Mr. Chang's ability is obvious to all, and he is indeed qualified to comment like this.

“In addition, because at the time of blade production, the multi-arc ion plating equipment in the factory was not yet in place, so the hot-end components had not yet used new coating technology, and the increase in temperature in front of the turbine was relatively limited.”

"Of course, on the other hand, the turbine front temperature of the Spey MK202 itself is already quite high. It is indeed true that the British can use such a high turbine front temperature to design such an engine with mediocre performance... tsk tsk tsk."

At this time, it would be difficult for Zhang Zhenhua and Zhong Shihong to answer the phone.

"Then... how much can some typical paper performance be improved?"

"To be more specific, we will know after bench testing."

At this time, a Jetta King stopped in front of the three people.

Naturally, Zhu Yadan was the one driving.

Chang Haonan opened the right rear door, turned back to the two people and continued:

"However, according to the performance calibration I did, the thrust at sea level can be increased to about 10000kg. The total weight of the engine, according to the national standard, should not be higher than 1750kg."

After saying that, he got into the car and signaled that the team could set off.

Only two people were left messy in the wind.

"This is called 'Don't have high expectations'?"

Zhang Zhenhua looked at Zhong Shihong next to him with a somewhat stiff movement.

You know, the sea level afterburning thrust of the Spey MK202 is 9300kg, the national standard dead weight is as high as 1842kg, and the thrust-to-weight ratio is only 5.05.

The turbofan 9A directly increases the engine's thrust-to-weight ratio by nearly 15%!

"As you know, Mr. Chang has always been very demanding on projects."

Zhong Shihong held up the cotton hat on his head.

He actually felt it was a bit outrageous, but in front of Zhang Zhenhua, he still maintained his demeanor and did not show any obvious surprise:

"In short, I have begun to look forward to the performance of the Turbofan 10..."