As the name suggests, anti-theft screws differ from ordinary screws in their core design purpose. They are engineered to prevent unauthorized disassembly and removal. Wrenches for standard external and internal hexagon screws are widely available, making such screws easy to take apart with the right tool-anti-theft screws are specially designed to address this issue.
There are various types of anti-theft screws, and the commonly seen carriage bolts actually have anti-theft properties. A carriage bolt features a round head with a neck, and is fastened with a nut on the reverse side. No tools can be used to remove it from the head side; the only way to disassemble it is to take off the nut from the reverse, which is usually sealed on the mounting base. This gives carriage bolts a certain anti-theft effect. Another type is the hexagon socket head cap screw, whose head has to be exposed due to installation design requirements-so how does it achieve anti-theft? A standard hexagon socket head cap screw has a recessed hexagonal hole, which can be easily unscrewed with a hexagonal wrench. However, this anti-theft version has a vertical cylindrical pin in the center of the hexagonal hole. In other words, a regular hexagonal wrench cannot fit into the hole at all, and the dedicated matching wrench is not available on the market, thus achieving the anti-theft effect.
This type of anti-theft screw with a central pin is low-cost and easy to manufacture. It can be produced simply by modifying the molds of standard hexagon socket head screws or pan head screws, with no difference in material cost or production time compared to ordinary screws. For this reason, many telecom base stations use such anti-theft screws for installation to prevent equipment damage.
The anti-theft principle of these screws is clear from the above drawing-simply put, it is to make it impossible for anyone to find a suitable tool for disassembly and assembly. Therefore, the key to designing anti-theft screws lies in the special shape of the head, and has nothing to do with the threads themselves. We can also design the head into a special-shaped structure, omit the tool hole for installation entirely, or even use a simple round head to achieve anti-theft. As the saying goes, mastery of one thing leads to understanding of all.
In many small household appliances used in daily life, manufacturers design many fixing screws to be unopenable with regular tools to prevent accidental operation by children-this design is also adopted for some fixing screws on automobile tires. Hence, such screws are also called tamper-proof screws. There are two types of molds for producing tamper-proof fasteners, one for tamper-proof screws and the other for tamper-proof nuts. Tamper-proof screws are mainly designed by changing the standard hexagonal socket to a pentagonal socket, octagonal socket, Torx socket, or Y-shaped socket, among other styles.
