Manufacturing Process of Bulletproof Helmets

I. Raw Material Selection: Laying a Solid Foundation for Safety

The protective performance of a bulletproof helmet begins with raw material selection at the source, where each type of raw material undergoes rigorous multi-dimensional screening. The core protective layer is made of ultra-high molecular weight polyethylene (UHMWPE) fibers or aramid fibers—materials that combine high strength and lightweight properties. Their tensile strength can reach 15 times that of ordinary steel, while their density is only 1/8 of steel, which minimizes the helmet’s weight while blocking projectile impacts.

Auxiliary materials are also carefully selected: the cushioning liner is made of high-density open-cell foam, which provides both energy absorption and breathability; the outer shell coating uses wear-resistant and corrosion-resistant polyurethane material, which has passed ultraviolet aging tests to ensure it does not peel off during long-term use. All raw materials have been certified by third-party testing institutions, and their physical performance indicators meet the national standard GB 2811-2019 and the international NIJ Level IIIA protection requirements.

Core Manufacturing Process: The Transformation from Fiber to Armor

1. Fiber Pretreatment and Weaving

First, the raw material fibers undergo low-temperature dehumidification and shaping treatment to remove moisture and improve fiber regularity, preventing stress concentration in subsequent processing. They then enter computer-controlled 3D weaving equipment, where a five-axial weaving process is adopted—warp yarns, weft yarns, and diagonal yarns interweave to form a three-dimensional network structure. Compared with traditional 2D weaving, this structure increases the impact resistance of the protective layer by 30%, effectively disperses projectile impact force, and prevents local cracking. During the weaving process, the equipment monitors yarn tension in real time, with the error controlled within ±0.5N to ensure uniform density of every inch of the fabric.

2. Molding: Precisely Shaping the Protective Form

After weaving, the fiber cloth is cut and stacked according to the preset number of layers (usually 16-24 layers, depending on the protection level), then placed into a custom mold for autoclave molding. The process parameters have been optimized through thousands of tests: the heating rate is controlled at 5℃/min, the pressure is maintained at 1.2-1.5MPa, and the constant temperature stage (120-140℃) lasts for 90 minutes to ensure the resin fully impregnates the fibers and cures. The mold is made of aviation-grade aluminum alloy, with a precision of ±0.1mm, which can accurately replicate the helmet’s streamlined design—ensuring a snug fit when worn, reducing air resistance, and avoiding stress concentration risks caused by sharp edges. After molding, a liquid nitrogen cooling process is used for rapid cooling to increase material crystallinity and further enhance protective performance.

3. Precision Processing and Component Integration

The molded helmet blank enters the precision processing stage: first, CNC machine tools are used for edge grinding to remove burrs and ensure smooth edges without sharp points; then surface treatment is carried out, including sandblasting for rust removal and electrostatic spraying, with the coating thickness controlled at 0.8-1.2mm to provide anti-slip, wear-resistant, and concealment properties. The cushioning liner adopts a 3D cutting process, designed to fit the contour of the head based on ergonomics, with multiple built-in energy absorption modules that can quickly absorb energy during an impact and reduce head acceleration. Finally, component integration is performed: impact-resistant polycarbonate visors (with light transmittance ≥95%, capable of withstanding high-speed flying debris), adjustable headbands, and buckles are installed. All components have passed tension tests and fatigue tests to ensure firm connection and reliable use.