Mid-October.

Yang Jie, along with Natasha and Adam Cohen, appeared in the rocket engine and rocket factory in Wenchang City, Qiongzhou Province.

Inside the rocket engine factory, Adam Cohen also looked at the rocket engine valve in the cryogenic test cabinet with interest.

The temperature inside the cryogenic cabinet is kept at minus 55 degrees Celsius, and the ratio of liquid nitrogen to alcohol is strictly controlled in order to achieve the required test temperature.

Ban Zhinon was also introducing technical things to Natasha and Adam Cohen at this time.

When he came to the tail nozzle welding section, Adam Cohen saw a huge conical nozzle fixed to a bench next to it, and next to it was a robotic arm welding, shining brightly between the welder and the tail nozzle.

Next to this set of equipment, several technicians are looking intently at the screen, which is an infrared image, which clearly shows the working status of the welding robot at this time.

"Ah, you even use robots for rocket engines?"

Adam Cohen said in surprise.

"Welding work like this is quite demanding for manual labor because the welded wall pipe is often less than 1 millimeter and the deformation caused by welding is overcome. In order to train such welders, it takes a lot of time, and the number of qualified welders trained is very small, and it takes a month for two skilled welding technicians to weld a nozzle at the same time. ”

Ban Zhinong said: "More importantly, but the structure of the nozzle is complex, and because of the huge shape, the welding deformation control requirements are high, a little crack or bubble can cause the rocket to be damaged during the flight of the nozzle, resulting in significant losses, this welding work has very high requirements for welding quality, and the labor cost is too high." ”

When the rocket is launched and flying, the temperature of the gas passing through the nozzle is between 1,000 and 3,000 degrees Celsius, and the technical team led by Ban Zhinong has increased the temperature of the combustion chamber by more than 3,000 degrees Celsius in order to obtain more thrust.

Although Yonghan Aviation Technology Co., Ltd. has developed a thermal barrier coating that can withstand more than 4,000 degrees, the life of the material is naturally not long at such high temperatures, and the material can maintain a temperature of about 4,000 degrees without creep and ablation for a long time.

Because of the small output of this coating material, it can only be evaporated on the inner wall of the combustion chamber and the nozzle, and after the coating, the temperature has dropped to 1200 degrees when it is transferred to the nozzle alloy body, so that the rocket engine can work for a long time, the outside of the nozzle still needs to use propellant to cool the nozzle. By making the structure of the nozzle into a sandwich, the propellant is rotated in the sandwich before entering the combustion chamber to take away the heat, ensuring that the nozzle will not overheat and can work for a long time.

"This welding robot was developed by your own company?"

Natasha asked Yang Jie at this time.

"Well, this is the laser welding equipment independently designed and manufactured by our group company, and our engineers have continuously experimented to achieve independent innovation and built a nozzle robot laser automatic welding equipment. ”

Yang Jie knew that the top welders like this before were all national treasures, because this kind of experience-based technology can only rely on talent and a lot of time training, and these welders have to hang sandbags on their hands during training.

As a reborn and scientist, Yang Jie has always held a concept of "equipment is more reliable than people", and the production process that can be replaced by machinery and equipment is definitely made with intelligent and automated equipment.

All the production plants under Huaxing Group have the highest degree of automation in China, and they are constantly upgrading equipment and processes, and those replaced equipment are given to these foundries of Fuyao Group.

This set of laser welding equipment does not need to use the X-ray online positioning system of inner wall ribs as before, which greatly reduces the complexity and cost of the equipment, and the deformation is controllable and can be directly formed during welding.

There is no such equipment in the world, but Huaxing Group now wants to develop what equipment and instruments can use the mature technology of some domestic research institutes and foreign technical products, so the research and development speed is extremely fast.

"It used to take us a month to weld such a nozzle, but with this equipment, it only takes us two days, and now we are still developing a new process, which makes it possible to reduce the processing time to less than 10 hours. ”

Ban Zhinong said with a smile.

Adam Cohen was surprised and said, "You guys are going to carry out large-scale production of rocket engines!"

"Yes, our purpose is to greatly reduce the manufacturing cost, shorten the manufacturing cycle, improve product quality, realize the mass manufacturing of products, completely reduce the cost of rocket launches, and strive to develop the aerospace market. ”

Yang Jie said with a smile: "The manufacturing cycle of rocket engines is generally 10 months, and I hope that this manufacturing cycle will be compressed to one month, so as to meet the more and more frequent launch tasks of our company in the future." ”

The rocket engine factory also built a huge indoor test bench next to the factory, surrounded by poured concrete, and the loud sound of the test was basically cut off.

Yang Jie and others also appeared at the test console at this time, the distance from the test bench was still very far, and it was also poured with concrete, which was also to prevent the rocket engine from being affected during the test.

The only way to confirm engine reliability is to test it directly with the finished product.

Inside the huge screen inside the test console, the engine is fixed to a special tilting bench, and the cooling system begins to spray water, creating a curtain of water to reduce the temperature and noise of the tail flame.

As the timekeepers counted to zero, the engine on the bench ignited, and the brightness of the tail flame sprayed out of the nozzle made the surroundings dim, and the tail flame directly washed the ground below, emitting a high-temperature steam, and the water curtain mixed into the tail flame, which was a real fusion of water and fire.

At this time, the infrared temperature detection device on the screen is displaying the infrared image and temperature of various parts of the rocket engine.

Even through the thick concrete, Yang Jie can feel the vibration of the rocket engine when it is working.

The thrust of the pump-back swing rocket engines with these four engines in parallel added up to 600 tons of thrust!

Because Ban Zhinong originally designed the engine thrust of 100 tons, but the actual thrust of the engine after production far exceeded the design target, reaching 150 tons of thrust!

In the original rocket design, the first stage of the rocket engine will be connected to four engines in parallel, and then two liquid rocket engines will be bundled, and the thrust will reach 600 tons, but after the rocket engine is produced, there is no need to bundle two engines at all, so the bundled rocket engine is canceled.

Testing an engine requires monitoring around 250 parameters to assess its quality, so many ignition tests are performed.

As a result of this test, about 12 tons of hydrogen fuel and 30 tons of liquid oxygen were burned.

Once the test is complete, the engine is sent back to the assembly shop for disassembly, where it is adjusted according to the test results, and then assembled before passing the final quality inspection before being sent to a nearby rocket production line for final assembly.