Micro‑precision screws usually refer to machine screws from M0.8 to M3. They are widely used in laptops, surveillance cameras, smart wearables, instruments and eyeglass accessories. Due to small thread diameter and shallow thread profile, these screws are prone to loosening under long‑term vibration and temperature cycling, leading to component displacement, falling‑off and equipment failure.

Four mainstream anti‑loosening processes for micro screws are widely adopted: nylon patch locking, nylon insert ring, thread stamping locking and structural pair locking.

Nylon patch screws have blue nylon adhesive pre‑coated on threads. After tightening, nylon fills thread gaps and provides friction‑based locking. It can be reassembled 2‑5 times and is popular for mass‑volume electronic assembly. Note that high temperature above 120℃ will damage the adhesive layer.

Nylon insert ring screws are fitted with nylon rings. Nylon deforms and fills thread gaps after tightening for stable re‑usable locking. Its outer dimension increases, so it is not fit for ultra‑narrow installation space.

Thread stamping locking deforms thread end by pressing mould for self‑locking. It has low cost yet works only for one‑time assembly. Anti‑loosening performance disappears after disassembly, not suitable for repair‑required products.

Selection tips: Pre‑coated nylon patch screws are preferred for repeated repair. Avoid nylon‑ring type for ultra‑thin compact devices. For high‑temperature environment, adhesive‑based locking shall be avoided; choose stamping locking or spring washer instead. Require anti‑loosening test reports and vibration verification during procurement.

Micro screws have limited mechanical strength. Tightening torque must be strictly controlled. Excessive torque causes thread stripping or screw breakage. Precision electric screwdrivers with torque limit are commonly used in electronic assembly lines to guarantee yield rate.