Dongfeng VL Bumper inner frame assembly 8406105-C4301

As the core load-bearing component of the bumper system, this inner frame features a multi-ribbed and box-type structural design optimized for absorbing and distributing impact forces. The frame is constructed with crosswise and longitudinal reinforcement ribs (typically 3-5 cross ribs and 2-3 longitudinal ribs, depending on size) that form a rigid grid structure—significantly enhancing its bending and torsion resistance. When the bumper receives an impact (e.g., low-speed collisions with obstacles or minor scrapes), the frame can absorb up to [add specific data if available, e.g., "5kN"] of impact force without permanent deformation, protecting the truck’s chassis, radiator, and other key components from damage. Additionally, the frame’s connection points to the chassis are reinforced with thickened steel plates (2-3mm thicker than the main frame body) to ensure secure attachment and prevent detachment during impacts

The main body of the bumper inner frame is made of high-strength cold-rolled steel (Q235 or Q345 grade)—a material chosen for its excellent tensile strength (minimum yield strength of 235MPa for Q235, 345MPa for Q345) and impact resistance, ideal for withstanding the harsh conditions of heavy-duty truck operation. To prevent rust and corrosion (a common issue for underbody components exposed to rain, mud, and road salt), the entire frame undergoes a rigorous

first, it is pickled and phosphated to remove rust and oil; then, it is coated with an electrophoretic primer (for deep corrosion protection); finally, it is sprayed with a high-temperature-resistant powder coating (typically epoxy-based) with a thickness of 60-80μm. This multi-layer coating ensures the frame maintains its structural integrity and appearance for 5+ years under normal use, even in high-humidity or corrosive environments

Designed to streamline the bumper installation process, this inner frame assembly includes pre-punched mounting holes and built-in positioning tabs that simplify alignment with other bumper components. The pre-punched holes (typically M8 or M10 threaded holes) are spaced according to Dongfeng’s OE standards, allowing the outer bumper cover (plastic or metal) to be directly bolted to the frame without additional drilling. The positioning tabs—small raised steel projections on the frame’s surface—help installers quickly align the frame with the chassis, reducing installation time by approximately 40% compared to non-tabbed frames. Furthermore, the frame’s design allows for easy removal and replacement: if the bumper is damaged in a collision, the frame can be detached from the chassis by removing a few bolts, without needing to disassemble other underbody components. This simplifies maintenance and reduces repair costs for truck owners and fleet operators