The bumper is a safety device that absorbs and mitigates the external impact and protects the front and back of the car body. Twenty years ago, the front and rear bumpers of cars were mainly made of metal materials. They were stamped into U-shaped channel steel with a thickness of more than 3 mm, and the surface was treated with chromium. They were riveted or welded together with the longitudinal beam of the frame, and there was a large gap with the body, as if it were an attached part. With the development of automobile industry, automobile bumper as an important safety device is also on the road of innovation. Today's car front and rear bumpers in addition to maintaining the original protection function, but also the pursuit of harmony and unity with the body shape, the pursuit of its own lightweight. To achieve this purpose, the front and rear bumpers of cars are made of plastic, known as plastic bumpers. The plastic bumper is composed of three parts: the outer plate, the cushioning material and the beam. The outer plate and the buffer material are made of plastic, and the beam is made of cold-rolled sheet with a thickness of about 1.5 mm and formed into a U-shaped groove; The outer plate and cushioning material are attached to the beam, which is attached to the frame rail screws and can be removed at any time. This plastic bumper uses plastic, basically using two kinds of materials, polyester and polypropylene, using injection molding method. There is also a kind of plastic called polycarbon ester series abroad, infiltration into the alloy composition, the alloy injection molding method, processing out of the bumper not only has high strength rigidity, but also has the advantage of welding, and the coating performance is good, the amount of more and more in the car. Plastic bumper has strength, rigidity and decoration, from the safety point of view, the car collision accident can play a buffer role, protect the front and rear car body, from the appearance of the point of view, can be naturally combined with the body in a piece, a whole, has a good decoration, become an important part of the decoration car appearance.
