What should I pay attention to when installing and using the self-locking tuning screw?

The installation and use of self-locking tuning screws need to focus on three cores: "protecting locking structure, ensuring tuning accuracy and adapting to working conditions". The key points for attention focus on four stages: preparation before installation, installation operation, working conditions adaptation and later maintenance, which directly affect its functional stability and service life.

First, preparation before installation: avoid basic risks

Inspection and preparation before installation is the premise to avoid subsequent failures, and attention should be paid to the screw state, tool matching and installation environment.

Check the integrity of screws, and it is forbidden to use damaged parts: after unpacking, it is necessary to check whether the locking structure of screws (such as nylon ring and metal elastic sheet) is intact one by one. If there are problems such as nylon ring falling off, elastic sheet deformation and thread bump, it is necessary to replace them immediately. For example, the nylon ring self-locking screw, if the nylon ring is cracked or displaced, will directly lead to locking failure, and shall not be used any more.

Match special tools to avoid loss of accuracy: tools that completely match the specifications of the screw head (for example, Allen wrenches should correspond to H3, H4 and other models, and torque wrenches should be calibrated to preset accuracy) should be used. It is forbidden to operate with adjustable wrench or tools that do not match the size. Inappropriate tools will cause the screw head to slip, and at the same time, the tightening torque cannot be accurately controlled, which will destroy the tuning accuracy.

Clean the installation site to remove impurity interference: before installation, it is necessary to clean the threaded hole and contact surface of the connected piece to remove impurities such as oil, iron filings and dust. Impurities will cause the screw thread to be stuck, which will affect the smoothness of tuning, and may also generate additional stress after tightening, leading to premature aging of the locking structure.

Second, the installation operation: control accuracy and strength

During the installation process, the operation methods should be strictly controlled to avoid damaging the screw function due to improper operation. The core precautions include torque control, tuning process and locking structure protection.

Strictly follow the torque requirements, and do not over-tighten: according to the specifications of screws (such as M3 and M5) and materials (such as titanium alloy and stainless steel), set the torque value according to the design requirements (usually marked in the product manual, such as the torque of M4 titanium alloy screws is 2.5-3 nm), and tighten with a torque wrench at a uniform speed. Excessive torque will lead to permanent deformation of locking structure (such as metal embossing) or thread slipping; If the torque is insufficient, the locking function cannot be activated, and the position locking after tuning will be affected.

Follow the "tuning-locking" process to avoid the reverse order: it is necessary to finish the precise tuning (such as fine-tuning the gap and angle of components) first, and then activate the locking structure by tightening after the parameters are confirmed. It is forbidden to lock the locking structure first and then try to tune it. For example, some screws need to be pre-screwed to a semi-tight state, and then fully tightened and locked after tuning. Reversing the process will lead to tuning jam and even damage the thread.

Protect the locking structure to avoid additional damage: when installing, it is necessary to avoid the screw from radial impact (such as hitting the head with a hammer), especially the fragile locking structure such as nylon ring and elastic sheet, which will be broken or displaced by the impact. For example, if the screw is stuck in the installation process, it is necessary to check whether there is impurity blockage first, rather than forcibly screwing it to prevent the locking structure from being damaged synchronously with the thread.

Third, the working condition adaptation: matching the requirements of the use environment

The function of self-locking tuning screw is greatly affected by temperature, humidity, corrosiveness and other working conditions, so it is necessary to choose the appropriate model according to the actual use scene and take protective measures.

Select the corresponding material and locking type according to the working conditions: in high-temperature environment (such as engine room, temperature > 150℃), it is necessary to choose high-temperature resistant metal elastic sheet self-locking screws to avoid using nylon ring screws (nylon rings are easy to soften and fail at high temperature); In humid or corrosive environment (such as the bottom of airplane wing, which is easy to contact with rain and salt), stainless steel or cadmium-plated and zinc-plated screws should be selected, and antirust grease should be applied after installation to enhance corrosion resistance.

Avoid direct use in an environment with excessive vibration: if there is high-frequency vibration at the installation site (such as parts close to the engine, the vibration frequency is more than ＞50Hz), a buffer gasket (such as silicone gasket) should be installed between the screw and the connected part to reduce the direct impact of vibration on the locking structure. Long-term high-frequency vibration will accelerate the wear of the locking structure and shorten the service life only by relying on the locking function of the screw itself.

Fourth, post-maintenance: extend the functional life.

Regular maintenance can find potential problems in time and avoid fault expansion, so it is necessary to focus on condition inspection and maintenance methods.

Regularly check the functional status and replace the aging parts in time: set the maintenance cycle according to the usage scenario (for example, the aerial equipment is inspected once every six months), and the inspection contents include whether the locking structure is aging (for example, the nylon ring is hardened and the elastic piece loses elasticity) and whether the screws are corroded or loosened. If the anti-loosening function is found to be decreased (if the screw can be slightly turned by hand), it is necessary to immediately replace the new screw and not to continue to use it.

Avoid destructive disassembly during maintenance: If it is necessary to disassemble the screws for maintenance, it is necessary to confirm the unlocking method of the locking structure first (for example, some screws need to press the unlocking plate, and some screws need to be unscrewed at a specific angle in the opposite direction), and forced prying or cutting is prohibited. For example, the metal elastic plate screw, which is forcibly disassembled, will cause the elastic plate to break and cannot be reused. The correct way is to operate according to the unlocking process to ensure that the screw can be completely disassembled and reused after inspection (if it is in good condition).

On the whole, the installation and use of self-locking tuning screws need "light operation, strict control and adaptation to the environment", and any negligence in any link may lead to the failure of its anti-loosening or tuning function, especially in the scenes with high reliability requirements (such as aviation and precision equipment), it is necessary to implement the precautions in every step of operation in order to give full play to its performance advantages.