As everyone knows, the US military's F-14 "Tomcat" carrier-based fighter is a classic combat aircraft, and its biggest feature is the design of the variable swept wing.

It can be called a miracle in the seventies, because the variable swept wing is not only complex, but also has very high requirements for the structural strength of the whole fuselage, and if there is a slight difference, the wing will easily cause the fuselage structure fatigue and the overall fuselage life will be reduced under the non-aerodynamic drag and load in the process of change; serious will easily lead to the disintegration of the fuselage and cause accidents.

Because of this, despite all the rage of variable-swept wing fighters, there are only two and a half in the world that can really produce them and use them on a large scale, two of which are the United States and the Soviet Union, and the other half are Europe.

Needless to say, the United States and the Soviet Union, from fighters to bombers, used variable-swept wings for a whole generation of models, and the reason why Europe said that it was half is because, except for the "Tornado" fighters, there was no series of variable-swept wing fleets.

The reason for this is so simple is that Europe lacks large electron beam welding machines to make larger central wing boxes that can withstand the aerodynamic structure of variable swept wings.

Yes, the key to solving the structure of the variable-swept wing fuselage is the central wing box, which has a very strong overall structure.

In general, in order to maintain the integrity of the overall structure, the application of the overall casting process is the safest, but in the field of aircraft manufacturing, especially in the manufacture of advanced aircraft, every inch of space is a valuable asset for designers, perhaps a joint, or need to install a certain equipment, or a controller connected to a certain part, in short, the huge central wing box, designers are impossible to ignore it as a blank.

This raises the question of how to maximize the retention of the structure and complex cabin required for the interior during casting.

In addition, all parts of the aircraft must be light and thin, take the central wing box skin of F-14 as an example, the thinnest titanium alloy skin is only 0025, which is only equivalent to the thickness of an A4 paper.

The overall casting is worry-free, but it can't do such an extreme degree, which is bound to require complex machining in the later stage, but the overall casting has been formed, and then it is difficult to use machining, and the impact on the overall structure can not be ignored.

Therefore, the best way is to manufacture them in sections, and then use welding to splice them into a whole to form an integrated overall structure.

Electronic welding plays a key role in this.

Due to the good stability of the electronic welding process, easy to control, energy concentration, fast speed, small welding deformation, good weld quality, all of the above, with the vacuum environment, can improve the utilization rate of materials, indirectly reduce the weight of the overall structure, increase the integrity of the components, improve the strength, is a rare precision welding process in the aerospace field.

Take F-14 as an example, its central wing box is 7 meters long and 09 meters wide, and the whole structure is composed of 53 titanium alloy parts, combined together for a total of 70 welds, which are manufactured by electron beam welding process, with a welding thickness of 12 to 572 mm and a total length of 55 meters.

As for the effect, not only compared with the traditional welding process, the overall structure of the F-14 central wing box using the electron beam welding process is reduced by 273 kg, and the overall strength is also very good, which can be seen from the subsequent F-14 accident, as long as it is not a particularly major air accident, the central wing box of the F-14 rarely breaks as a whole.

Even in some seemingly serious accidents, the central wing box is still intact, and it can be used as a spare part after a little processing after recycling, which shows how excellent the overall central wing box of the F-14 is.

Now the production of F-14 central wing box EJ9 electron beam welding machine in front of Zhuang Jianye and others, to say not excited is absolutely nonsense, because what does this mean to trouble the advanced light transport platform of 5 meters long, 23 meters wide, 08 meters high overall central wing box is a fall.

It is important to know that the EJ9 electron beam welder, which can produce the F-14 7-meter-long and 09-meter-wide central wing box components, has a length of 75 meters, a width of 28 meters, a height of 25 meters, and a space area of 532 square meters.

Equipped with 45kw and 110kw two electron beam welding guns, the welding mechanism is mobile automatic welding, the electron beam welding gun is set on the gantry hanger in the vacuum chamber, and can move along the length, width and height three directions.

It belongs to the advanced level of the mid-seventies.

Yes, even if it is the same F-14, it is still not the most cutting-edge production equipment in advanced developed countries, after all, it is now the end of the eighties, the electron beam welding vacuum chamber in Western developed countries has been hundreds of square meters, and the electron beam welding gun has been replaced by a flexible robotic arm, with the numerical control program written by high-precision industrial control software, it has already broken through the simple movement of three directions of length, width and height.

Similar to complex circular motion, multi-fold angle movement, and rotary motion can be easily realized.

Among them, the new vacuum welding equipment built by the United States for YF-22 is more ~~, not only the electron beam welding gun can achieve multi-angle movement, but also can be accurately adjusted according to the numerical control program according to different parts and different thicknesses of components, with a higher degree of automation and a stronger degree of integration, far ahead of the world.

In order to produce the Tu-160 strategic bomber and the "Buran" space shuttle, the Soviet Union manufactured a super-large electron beam welding machine with a vacuum chamber volume of 673 square meters in the Ural Mountains at any cost; later, it felt that it was not enjoyable to build a 1,300-square-meter extra-large electron beam welding machine, known as the world's largest extra-large electron beam welding machine.

As a result, it was made, but when it was used, it was found that these two big babies were super power consumers, especially the 1300-square-meter extra-large electron beam welding machine in the back, as long as it was used, the power of the entire Ural military production base 80 was like vacuum, and it was taken away by this product.

Therefore, the Soviets had to coordinate with other departments every time they used it, and they could only use it during the peak period of electricity consumption from 2 to 4 o'clock in the morning, otherwise as soon as the goods were turned on, the Urals would have to lose power.

Of course, Tengfei Group will not engage in such a big thing, because it is equivalent to the electricity of the entire southwest to supply such a thing, which is too cost-effective.

Of course, the current EJ9 electron beam welding machine is indeed a bit small, and the welding range is still somewhat limited, but Zhuang Jianye is not very worried, because Peng Chuan and Wei Guangping have taken their respective teams to seriously study this key equipment, with their attainments in automatic assembly, flexible tooling, electrochemical punching, and pulsating production lines, the so-called key equipment such as EJ9 electron beam welding machine is in some respects a layer of window paper.

This Peng Chuan didn't even bother to knock on the door, asked Xiao Zheng next door, and pushed the door in directly, and then slapped the drawings in his hand on the desk, Zhuang Jianye unfolded it, and sure enough, the EJ9 electron beam welding machine for aero engines designed with double gun heads using mechanical arms came out.

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