Does the car collision beam really prevent collision

　　The car collision beam is indeed "collision resistant", but its core function is not to ensure that the vehicle remains intact in high-speed collisions, but to protect the core structure of the vehicle and reduce maintenance costs at a relatively low cost in medium and low-speed collisions. You can follow us to understand its true function from the following aspects:

　　1. Main function: "Economic protection shield" for medium and low-speed collisions

　　Protecting the longitudinal beam and core structure of the vehicle: The collision beam (especially the front collision beam) is connected to the longitudinal beam of the vehicle body through an energy absorbing box. In low-speed collisions (such as daily urban rear end collisions, usually referring to speeds below 15 kilometers per hour), the collision beam is a contact point. Its function is to transmit the impact force, allowing the connected energy absorbing box to absorb most of the impact energy through its own deformation, thereby preventing the impact force from being directly transmitted to the more expensive and core body longitudinal beams and passenger cabin structures. Once the longitudinal beam deforms, the vehicle is considered to be "damaged", with extremely high repair costs, and may affect the safety structure and driving stability of the vehicle.

　　Reduce maintenance costs: In low-speed collisions, the ideal situation is to only damage the replaceable crash beam and energy absorbing box, while the main body structure of the vehicle remains intact. This way, maintenance is faster and cheaper. This is the main economic consideration in the design of anti-collision beams.

　　2. Secondary but crucial role: optimizing the transmission path of high-speed collision forces

　　Participate in collision force transmission: In high-speed frontal collisions, the strength of the collision beam itself (especially steel or aluminum alloy) helps to distribute the collision force more evenly to the longitudinal beams on the left and right sides, guiding the impact force to propagate backward along a predetermined path, and buffering it through the layers of energy absorbing zones in the engine compartment (such as longitudinal beam crushing and engine sinking), avoiding serious deformation of the passenger compartment.

　　Dealing with small area offset collisions: Good anti-collision beam design (such as using high-strength materials and wider coverage) can more effectively transmit the impact force to the side longitudinal beams and body structure in 25% small offset collision tests, preventing wheels from entering the passenger compartment and improving safety.

　　3. Clarification of Common Disputes and Misconceptions

　　Is it "iron sheet" or "steel beam"? Materials are key.

　　Early or low-end models may use single-layer stamped steel plates or even engineering plastics with limited strength.

　　Mainstream car models often use multi-layer rolling or extrusion structures made of high-strength steel, ultra high strength steel, or aluminum alloy, which have much better strength, lightweight, and energy absorption effects.

　　The rear anti-collision beam was once simplified by some manufacturers and has now become a standard configuration, but its material and strength are usually not as good as the front anti-collision beam.

　　It is not a "diamond unbreakable" bumper: the crash beam is installed inside the bumper skin. In high-speed collisions, it cannot make the vehicle "undamaged", and it will also undergo severe deformation or even fracture, which is a normal energy absorption process.

　　Consideration for pedestrian protection: The design of modern car front crash beams also needs to take into account pedestrian protection. Usually, soft foam or plastic structure will be added in front of the anti-collision beam as a buffer, which can reduce the injury to the legs of pedestrians in case of collision between vehicles and pedestrians.

　　Conclusion: Value judgment of anti-collision beams

　　It is necessary: a modern car with standardized design must be equipped with front and rear collision beams (and their energy absorbing boxes). Without it, any minor collision would directly damage the body frame, making safety and economy impossible to discuss.

　　It is a part of the safety system: the collision beam is the starting point and important link of the collision force transmission path in the passive safety system of the vehicle, but it is not the whole. The overall safety performance of a vehicle depends on the overall design of the body structure, material strength, energy absorption zone settings, seat belts, airbags, and other systems working together.

　　The true meaning of "collision avoidance": Its "collision avoidance" is more accurately described as "responding to collisions with guidance and buffering", with the core goal of "preserving the larger (body structure) and minimizing the smaller (self components)", while protecting the safety of passengers and minimizing maintenance losses to the greatest extent possible.

　　So, the answer is yes, car crash beams really prevent collisions. But please understand its mission correctly - it is a shrewd "one line of defense commander" whose strategic value lies in using controllable sacrifices to protect more important core positions, rather than a "war god" who can withstand all attacks.