What are the advantages of self-locking tuning screws in aviation field?
You pay attention to the application of self-locking tuning screws in the aviation field. This breakthrough point is very valuable, which accurately points to the dual core requirements of aviation equipment for fastener "reliability" and "functionality". Self-locking tuning screws are used in the aviation field, and their core advantages lie in giving consideration to the safety of anti-loosening and self-locking, the functionality of precise tuning, and the stability of adapting to complex aviation working conditions, which can effectively solve the problems that traditional screws are easy to loosen and have insufficient debugging accuracy in high-altitude environment.
1. Self-locking and anti-loosening: to ensure the structural safety in extreme environment at high altitude.
Aviation equipment has been in the extreme environment of high-altitude vibration, drastic temperature change (-50℃ to 150℃) and sudden air pressure change for a long time. Traditional screws are easy to loosen due to vibration, which may lead to equipment failure and even safety accidents. The anti-loosening design of self-locking tuning screws can avoid this risk from the root.
Built-in locking structure, no need for additional locking accessories: This type of screw usually integrates locking structures such as nylon ring, metal embossing, wedge thread, etc., for example, nylon ring self-locking screw, which generates lasting friction through the interference fit between nylon ring and thread, and can avoid thread loosening even in continuous vibration (such as engine running and airflow turbulence), without adding additional washers, cotter pins and other parts, thus reducing the number of parts and assembly complexity of aviation equipment.
Stable anti-loosening performance, suitable for wide temperature working conditions: its anti-loosening structure (such as metal elastic sheet) can maintain elasticity at extreme temperature, and will not cause anti-loosening failure due to softening at high temperature or brittle cracking at low temperature. For example, in the engine compartment of an aircraft, the screws have to withstand the high temperature and vibration generated by the engine operation, and the anti-loosening performance of the self-locking tuning screws has no obvious attenuation in the range of-50℃ to 200℃, which is far superior to the traditional mechanical locking methods (such as double nuts) that rely on screws, and the latter is prone to stress relaxation in temperature changes.
Second, precise tuning: to meet the requirements of high-precision parameters of aviation equipment.
Aviation equipment (such as radar antenna, navigation system, and engine control system) requires extremely high accuracy (usually controlled at 0.01mm level) for the installation position, clearance, and pre-tightening force of components. The "tuning" function of self-locking tuning screws can realize accurate adjustment and locking of parameters and reduce debugging errors.
The thread precision is high, and the adjustment process is controllable: the thread of the self-locking tuning screw is processed with high precision (usually at the accuracy level of 5H/6g), and the pitch error is ≤0.01mm, so that the precise control of tiny displacement can be realized during rotation. For example, in the phase adjustment of radar antenna, the angle of the antenna unit can be fine-tuned by rotating the screw, and the displacement of 0.05mm can be achieved every 1/4 turn. After adjustment, the position is locked by the self-locking structure to avoid parameter drift.
Integrated pre-tightening force control to avoid over-tightening: some models of self-locking tuning screws have built-in torque feedback structures (such as torque fracture grooves and elastic washers). When the tightening torque reaches the preset value, it will send out feedback signals through fracture or elastic deformation to ensure the consistent pre-tightening force of each screw (error ≤5%). This is very important for the connection of the cylinder block and the fixing of the fuselage skin of the aero-engine, and can avoid the deformation of parts or the failure of seals caused by uneven pre-tightening.
3. Lightweight and high reliability: Adapting to the requirements of aviation "weight reduction" and "long life"
In the aviation field, there are strict requirements on the weight of equipment (a large amount of fuel consumption can be reduced by losing 1kg) and the service life (usually more than 10 years without failure). The self-locking tuning screw can meet these two points in both material and structural design.
High-strength and lightweight materials are adopted to reduce the weight of equipment: titanium alloy (TC4), high-strength aluminum alloy (7075-T6) or special stainless steel (17-4PH) are mostly used for this type of screws, which are 30%-50% lighter in weight and higher in strength than traditional carbon steel screws (for example, the tensile strength of titanium alloy screws is ≥900MPa, far exceeding the 600MPa of carbon steel). For example, titanium alloy self-locking tuning screws are used in the flap adjustment mechanism of aircraft wings, which can reduce the overall weight of the wings and improve flight efficiency while ensuring structural strength.
Structural integration reduces hidden trouble: traditional debugging requires the combination of "adjusting screw+anti-loosening parts", and the fit gap between parts is easy to become a fault point (such as dust accumulation and corrosion in the gap), while the self-locking tuning screw integrates the functions of "adjusting" and "anti-loosening" without additional fit gap, which can effectively resist the humidity change in high altitude (such as condensed water in high altitude) and the corrosion of pollutants (such as oil pollution in engine exhaust gas).
Fourth, convenient assembly and maintenance: improve the efficiency of aviation manufacturing and maintenance
Aviation manufacturing and maintenance require extremely high man-hour efficiency (for example, aircraft maintenance needs to be completed in a short time). The structural design of self-locking tuning screws can simplify the assembly process and reduce maintenance costs.
Single tool operation, high assembly efficiency: the "adjustment-locking" of traditional screws requires multi-step operation (such as adjusting the position first, then installing the locking nut), while the self-locking tuning screw can complete the whole process of "adjustment-locking" with only one wrench, and the assembly time is shortened by more than 50%. For example, in the installation of aircraft interior panels, workers can quickly adjust the flatness of the panels and lock them without repeatedly disassembling the locking parts.
Convenient adjustment during maintenance, without destructive disassembly: when aviation equipment is overhauled, if it is necessary to readjust parameters (such as the calibration of navigation system), just loosen the self-locking structure (such as pressing the elastic unlocking piece) to rotate the screw again, and then re-lock it after adjustment, without replacing the screw or destroying the surrounding structure. Compared with traditional locking screws (such as screws fixed by spot welding), this greatly reduces the maintenance cost and the risk of equipment damage.
To sum up, the self-locking tuning screw perfectly adapts to the strict requirements of fasteners in the aviation field through the four advantages of "self-locking and anti-loosening", "precise tuning", "lightweight and high reliability" and "convenient maintenance". At present, it has been widely used in aircraft engines, radar systems, fuselage structures, airborne electronic equipment and other core parts, and has become one of the key components to improve the safety and performance of aviation equipment.
