The Military-industrial Scientific Research System of the Academic Master Chapter 319

Chapter 319 Foreign objects in the air intake, hidden dangers solved! (Additional update 45 for the leader [the free agent])

 Actually, Chang Haonan doesn't have much to say.

 Now that the problem has been identified, the natural next step is to solve the problem.

Aircraft manufacturing is an extremely complex industrial process. Even more than 20 years later, many steps are still highly dependent on manual operations. In this process, it is almost impossible to produce metal remnants such as broken rivets and metal shavings. situations to avoid.

But under normal circumstances, firstly, according to regulations, parts should be inspected and cleaned before the end of each step in the final assembly process. This step should be able to remove most foreign objects on the surface of the workpiece. Secondly, even in some difficult cases, There are still some fish that have slipped through the deep holes that were inspected and cleaned, and they cannot easily get into the air intake.

As for the fact that prototype No. 1001 was not inspected and cleaned inside the air intake before delivery...

Chang Haonan glanced at the 132 factory representative who lowered his head and did not even dare to express his anger, and felt that the possibility was probably relatively low.

Given the importance of Project No. 10, all inspection processes must be repeated many times during the final assembly process.

Furthermore, even if we only judge from logic, if the quality management of Factory 132 can be so outrageous, then similar accidents should have happened long ago.

 Thinking of this, Chang Haonan quickly ran through the aircraft manufacturing process he had learned from Factory 112 in his mind, and then stood up.

 Before he could speak, and no one knew who started it, there was a burst of applause in the conference room.

 It was sparse at first, but almost instantly it became like a flood.

Chang Haonan raised his hand and pressed down, but it had no effect.

He noticed that the eyes of the participants, especially those from the test flight station and assembly workshop, had changed significantly compared to the previous days, and even compared to this morning.

That's the difference between "hearing that someone is awesome" and "realizing that someone is really awesome."

 It wasn't until about a minute later that the applause finally subsided.

“First of all, judging from the content of the inspection report, the metal debris attached to the end of the inlet and the engine blades can basically be determined to come from the drilling and nailing process during the riveting process.”

 Although this is a problem that everyone is already aware of, when it was formally summarized at the meeting, many people still felt a little bit in their hearts.

 Especially Xue Chishou.

As the chief engineer, he will inevitably be held responsible if such a large quality defect occurs during the production and manufacturing of the prototype.

Of course, he has also been mentally prepared for this.

However, just when Xue Chishou was about to make some self-criticism, Chang Haonan immediately changed the subject:

“But I think this is not a problem caused by the lack of implementation of production responsibilities or quality inspection rules. The main reason should be at the technical level.”

This sentence made many people feel a little calmer in their uneasy hearts.

"Compared with the various types of J-7 aircraft produced by Factory 132 in the past, Project 10 has unprecedented complexity in process and design, and the standards for production and testing cannot be improved overnight. In other words, many aircraft that were not available before The problematic operating procedures and production regulations may cause problems now.”

"So, in view of the current situation, I think there are two tasks that should be carried out immediately. One is to conduct a thorough inspection of the aircraft and conduct a thorough inspection of the excess objects that accidentally fell into the body cavity during the skin riveting process. To fix the leak, the second is to comprehensively check the design of the aircraft and find out where the foreign matter in the aircraft cavity enters the air intake.”

 After the brief speech, Chang Haonan returned to his seat.

Although he was invited to serve as a consultant for Project No. 10 and has considerable authority and say in the project, he is not an internal staff member of the 611 Institute and the 132 Factory after all, and he certainly cannot say too much about more specific responsibilities.

 That is a matter for their organizational department.

 “I would like to add two more points.”

Xue Chishou slightly brought the microphone in front of him,

"No matter what the cause of the problem is ultimately investigated, the main responsibility lies with me, so everyone should not have too much psychological burden at work. In addition, after the investigation is completed, corresponding production plans must be formulated based on the characteristics of the J-10 Rules and regulations ensure that no excess material is allowed to enter the body cavity in any process of production in the future.”

 “The meeting is dismissed!”

 After clarifying the next tasks and taking the reassurance given by Xue Chishou, the haze of the failure of the first test run was finally cleared away, and everyone quickly started follow-up work according to the arrangements at the meeting. Not to mention that Factory 132 turned around and directly launched a "Quality Culture Month" construction activity. On the side of Factory 611, the inspection speed of the air inlet design was faster than Chang Haonan thought.

Early on the morning of the third day, he had just finished breakfast and came to the office when he received a call from Yang Wei:

“The connection between the air inlet and the body cavity has been found.”

 “So fast? I'll be there soon.”

A few minutes later, Chang Haonan found Yang Wei buried in a pile of drawings in a design room—

Since the design of Project No. 10 began in the early 1990s, and the basic design was completed before Chang Haonan was reborn, there was no opportunity to use digital design technology.

 At present, Institute 611 has begun to organize some manpower to absorb relevant experience from Institutes 601 and 603, but this work is destined to be impossible to complete in a short time.

 So I still have to turn over the paper drawings slowly.

"Chang Gong, I confirmed several times yesterday that the J-10's air inlet has no physical connection with cavities such as the wings and the fuselage frame. Even if foreign matter remains in these parts, it is absolutely impossible to be sucked into the air inlet. , so I changed my mind this morning, look here.”

Yang Wei said and pointed to several places near the entrance of the air intake.

"In order to ensure effectiveness and reliability under various working conditions, the binary three-wave system adjustable air inlet contains several spherical one-way valves. The manufacturing process of this component is to install the spring, bracket and valve inside the shell Then it is closed directly, which is a part that cannot be decomposed after it is offline. "

“I asked the manufacturer responsible for manufacturing this valve and learned that they used to use a simple kerosene flushing method to clean it. However, after analysis, this method is not good at removing foreign matter that may remain inside the housing.”

"Under normal circumstances, this valve should be closed during engine operation, but if something is stuck in the bearing part, it will cause poor reset. In this case, the strong negative pressure inside the intake duct is likely to cause the inside to Suck out the metal foreign objects!”

Chang Haonan took several design drawings of the air inlet and the spherical one-way valve, spread them out on the table and observed them carefully for a few seconds.

Then he remembered that he had seen a similar structure before.

“Wait a minute...shouldn't this thing have a dedicated cleaning spindle?”

“Special mandrel?”

Yang Wei was stunned:

“They didn't mention it. They said it was a direct high-pressure fluid flushing method.”

"Well…"

Chang Haonan realized that the cleaning tool he had seen in his previous life should have been produced during the process of solving the problem after the J-10 failed two consecutive test runs.

 Fortunately, the structure is not complicated, and he can easily come up with the design drawings by working backwards on site.

 “Do you have a computer? It has drawing tools.”

 “There's one next door, I'll take you there.”

At noon that day, Chang Haonan handed a printed drawing to Yang Wei.

“The principle of this equipment is as shown in Figure 2. Before cleaning, use the mandrel shown in Figure 3 to push in, push open the valve 10, and then use reverse pressure to flush..."

Yang Wei was stunned as he listened to Chang Haonan's introduction.

 After a long time, he took the drawing from the latter and said with emotion:

“I used to think that I was somewhat competent in engineering.”

“Now it seems that we still have to continue to pursue progress...”

 (End of this chapter)

Chapter end