A car steel wheel is a barrel-shaped, center-mounted metal part of a tire that supports the tire inside profile. Also known as rims, rims, wheels, tire bells. Hub according to the diameter, width, molding methods, different types of materials. Hub size is actually the diameter of the hub, we often hear people say that the 15-inch hub, 16-inch hub such a statement, of which 15,16 inches refers to the size of the hub. Generally in a car, if the wheel hub size is large and the flat ratio of the tire is high, it can play a very good tension effect on the vision, and the stability of the vehicle control will also be increased, but then there are the added problems of increased fuel consumption. There are many main parameters in wheel machining, in the processing must pay attention to control the parameters in a reasonable range, otherwise it will affect the structure and performance of the Steel Rim Wheel.