Trim Head Screws

The material selection of Trim Head Screws directly affects its corrosion resistance and applicable environment. Commonly used materials include mild steel, stainless steel and copper alloy. Taking stainless steel SUS304 as an example, according to the ASTM B117 salt spray accelerated corrosion test standard, after surface passivation treatment, the screw can maintain no matrix red rust for 500 hours in a neutral salt spray environment with a concentration of 5% sodium chloride, while ordinary galvanized carbon steel screws can only withstand 200 hours under the same conditions, a gap of 2.5 times. At the same time, according to ISO 3506-1 regulations on fastener hardness, after cold work hardening, the surface Vickers hardness of SUS304 can reach 280 to 320 HV. This hardness not only improves the scratch resistance, but also allows the thread to maintain its shape integrity during repeated screwing. It is especially suitable for humid or weakly corrosive working conditions such as outdoor furniture, ship outfitting and chemical equipment, effectively extending the maintenance cycle and reducing the frequency of replacement.

In terms of installation characteristics and anti-loosening reliability, the head geometry and thread parameters of decorative head screws jointly determine their torsional and vibration resistance. According to the recommended limits for the screwing-in torque of self-tapping screws in Part 15 of DIN 267, for decorative head self-tapping screws of ST4.2 specification, it is recommended that the maximum screwing-in torque should not exceed 2.5 Nm, and the breaking torque should not be less than 4.5 Nm. The ratio between the two is approximately 0.56. This safety margin ensures that no head breakage or notch damage will occur during normal tightening. In addition, according to SAE J933's cyclic test on screw locking performance, after this type of screw is subjected to 200 axial vibration loads, the residual pretightening force can still maintain more than 85% of the initial value. This is due to the special serrated tooth design on the lower end surface of its head, which can be embedded in the surface of the workpiece to generate micro-occlusion, thus effectively resisting loosening. It is widely used in assembly scenarios such as power tool casings, automotive interior parts, and household appliances that are subject to continuous dynamic loads.

Obtain drawings from customers or create drawings based on their specifications or samples.

The drawings, product raw materials, surface treatment, and other details are attested to by both parties.

Provide a quote, confirm the order quantity, and include all relevant information.

Like the terms of payment, the terms of trade, the kind of packaging, etc.

When manufacturing the goods, adhere precisely to the original drawings and samples.

After a final inspection, it was meticulously packaged and delivered to the customers.

Hot Tags: trim head screws, China trim head screws manufacturers, suppliers, factory