The titanium alloy screw itself has high hardness and good strength, but to achieve true “anti-theft”, it is necessary to start from the two aspects of “anti-theft of the screw's own structure” and “anti-theft of supporting tools” to form a system.
Screw head type anti-theft
This is through the design of a special, unconventional screw head type, so that ordinary screwdrivers and wrenches cannot be twisted.
One-way screw (one-way rivet screw)：
Principle: The screw head is designed to be similar to a “barbed” or slope shape. It can only be screwed in clockwise with a screwdriver. When it is counterclockwise, the screwdriver will slip and cannot be screwed out.Commonly used in the protection of public facilities.
Advantages: Simple installation, intuitive anti-theft effect, and low cost.
Disadvantages: It is a one-time or destructive disassembly design, and it needs to be violently dismantled for later maintenance.
Special-shaped screw head：
Principle: A head type that can only be driven by market-specific tools.For example：
Plum blossom hole with column/flange ear: such as plum blossom T-type, plum blossom safety type.
Three-winged/four-winged/serpentine head: there is a bulge in the center, and ordinary one-word and cross-shaped heads are useless.
Hexagon socket with column/one-way hexagon socket.
Triangular head, square head and other non-standard head types.
Advantages: Special batch heads are required, good anti-theft, and can be disassembled repeatedly (with tools).
Disadvantages: If the dedicated batch head is improperly managed and flows into the outside world, the anti-theft will decrease.
Headless screw (anti-theft bolt)：
Principle: After installation, the screw head is broken or there is no exposed head at all.For example：
Broken tail anti-theft bolt: When tightened to the set torque, the tail guide column breaks, leaving only a smooth cylinder.
Inner pentagonal/inner plum countersunk bolt: after installation, it is flush with the surface and cannot be clamped with pliers.
Advantages: It is physically impossible to apply torque from the outside, which is one of the high-level anti-theft.
Disadvantages: Installation and disassembly are complicated, special tools and processes are required, and they are mostly used for permanent or semi-permanent fixation.
Auxiliary mechanical structure anti-theft
Additional protective cover/cap：
On the head of ordinary or special-shaped screws, screw a protective cap with a special thread.You need to open the protective cap before you can touch the internal screws.The protective cap itself can also use a special-shaped head.
Welding/point riveting：
After the screw is installed, tiny welding or point riveting is performed on its head to fuse it with the connecting piece.This is a thorough anti-disassembly method, but it is permanently fixed.
Nesting/string connection structure：
Use multiple screws to nest and lock each other, or string all parts with a main bolt, and finally use anti-theft measures on the head of the main bolt.
If you want titanium alloy screws to be anti-theft, it is important to choose or customize an unconventional screw head type that requires special tools to drive.
