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Do you still remember the first time you took a plane and saw the flickering wings and flaps? China Cheap Price bronze pipe fittings
Some netizens suspect that the quality of the aircraft is not good enough.
In fact, the wings are far tougher than we thought. And to ensure that it jumps up and down but is still safe, it is the unremarkable rivet.
It is said that a C919 aircraft uses millions of rivets; an airliner A380 uses more than 5 million rivets.
So why do airplanes usually knock millions of nails over welding or gluing? China Cheap Price bronze pipe fittings
▌Aircraft also loves to lose weight
“Strive for every gram of weight.” is the motto of every aircraft. learned from humans
Therefore, thin and light models are also popular as the skin of aircraft clothes. For example, the C919 uses a larger proportion of composite materials to reduce the structural weight of the aircraft.
The skin that is too thin will increase the difficulty of welding, and the composite material of the skin will be more easily damaged by welding, so different materials have to be connected by rivets.
Nails on airplanes have special functions
The specific strength of rivets on the plane is required to be as high as 1100 MPa, which is equivalent to the weight of 10 cars on an area of 1 square centimeter.
The machining accuracy of rivets is controlled at the micron level. The first one was almost identical to the tens of millions that followed. China Cheap Price bronze pipe fittings
One micron is about one-eighth the diameter of an adult hair
Other than that, millions of rivets don’t stop the plane from flying. World War II data show that solid countersunk rivets can reduce aircraft drag by 3%.
Therefore, the parameters of the rivets produced by the iron-clad assembly line have very small errors, which are trustworthy in terms of quantitative production and quality control.
If welding technology is used to join aircraft skins, the quality of production depends on the skill of the welder. If the welding is too thin or too thick, the aircraft will have more safety hazards.
Adhesives are currently not resistant to high temperatures, so even if the whole body of the aircraft is glued, key parts such as the engine can only be fixed and sealed with “reliable” rivets. China Cheap Price bronze pipe fittings
Rivets make planes live longer
An aircraft needs overhaul at the end of every flight. The substitutability, stability and many other advantages of rivets can make the aircraft “service” longer.
How to replace a broken rivet?
Generally use “frozen rivets” to replace. That is, the rivets are quickly frozen after quenching, and must be riveted within fifteen minutes when used.
The strength of this “frozen rivet” increases at room temperature, thereby enhancing the stability of the riveted structure.
The internal frame of the fuselage requires a lot of rivet connections
What happens if the rivet is loose? China Cheap Price bronze pipe fittings
A loose nail could cause the aircraft to display a malfunction message, requiring the maintenance staff to work overtime day and night to find the wrong nail.
In 2016, in order to eliminate the fault of an A320 aircraft, the maintenance staff continued to work hard for three days and three nights. After checking all possible faults one by one, they finally found a loose one among hundreds of data pins with a diameter of less than 1 mm. .
Aircraft riveter.
Although it is a lot of work to troubleshoot nails, there is no need to worry. Aviation screws are self-locking and the chance of loosening is minimal.
Therefore, due to various restrictions, most of the planes seen at present are made of nails.
The scattered aircraft skin is threaded through rivets, and finally becomes an air shirt, allowing the flaps to dance flexibly. China Cheap Price bronze pipe fittings
Press riveting is a riveting method, which refers to the use of external pressure to change the plasticity of the material in the riveting process, so as to enter the special prefabricated groove in the riveting screw and nut structure, so as to achieve reliable connection between parts.
Ordinary low carbon steel, aluminum alloy plate, copper plate and other materials are usually used for crimping rivet standoffs. Some materials with excellent materials, such as stainless steel and high carbon steel plates, generally use special and high hardness rivet nuts, so in general pressure riveting studs and pressure riveting nut sheet metal parts, stainless steel is rarely used. . The pressure riveting screws and nuts are the same as the pressure riveting studs, and stainless steel is less used.
Through the analysis of the pressure riveting process and the introduction of common pressure riveting parts and their processes, combined with the quality control method of the pressure riveting process, the pressure riveting process is discussed. China Cheap Price bronze pipe fittings
