There are two common forms of rims: deep groove rims and flat bottom rims, in addition to split rims, semi-deep groove rims, etc. Deep groove rims are used for cars and light off-road vehicles; flat-bottomed rims are used for medium-duty trucks; split rims are used for medium and heavy-duty off-road vehicles.
There are two common forms of rims: deep groove rims and flat bottom rims, in addition to split rims, semi-deep groove rims, etc. Deep groove rims are used for cars and light off-road vehicles; flat-bottomed rims are used for medium-duty trucks; split rims are used for medium and heavy-duty off-road vehicles.
A wheel rim, commonly known as a rim, is a component that mounts and supports the tire on the periphery of the wheel, and forms the wheel with the spokes. The rim and spokes can be integral, permanently attached or detachable.
Deep groove rim
This kind of rim is integral with a deep groove in the middle of its section, and is mainly used for passenger cars and light off-road vehicles. It has a shouldered flange for placing the bead of the outer tire, and its shoulder is usually slightly inclined to the middle, and its inclination angle is generally 5 degrees ± 1 degrees. The maximum diameter of the inclined portion is called the joint diameter of the tire bead and the rim. A deep groove is made in the middle of the section to facilitate the disassembly and assembly of the tire. The deep groove rim has a simple structure, high rigidity and low mass, and is most suitable for small-sized tires with high elasticity. However, larger and stiffer tires are difficult to fit into such an integral rim.
flat rim
There are many structural forms of this rim, as shown in Figure 3 is a form commonly used in trucks in my country. The retaining ring 1 is integral, and an open elastic locking ring 2 is used to prevent the retaining ring from coming out. When installing the tire, first put the tire on the rim, then put the retaining ring, and push it inward until it crosses the annular groove on the rim, and then insert the open elastic lock ring into the annular groove.
split rim
This kind of rim is composed of inner and outer parts. As shown in Figure 4, the width of the inner and outer wheels can be equal or unequal, and the two are connected together by bolts. When dismounting the tire, just remove the nut. The retaining ring 3 shown in FIG. 4 is detachable. Some have no retaining ring, and the rim is made into one piece with the inner rim instead of the retaining ring, and the inner rim and the spoke are welded together. Dongfeng EQ2080 and Yan'an SXZ15O car wheels are rims that use this form.
Since the rim is the basis for the assembly and fixing of the tire, when the tire is mounted on a different rim, its deformation position and size also change. Therefore, it is best to use the specified standard rims for each type of tire, and if necessary, rims with similar specifications to the standard tires (allowable rims) can also be used. If the rim is not properly selected, it will cause early damage to the tire, especially when used on a rim that is too narrow.
Representation of rim specifications
The rim specification code, its nominal width and nominal diameter are expressed in inches. The connecting symbol (* or -) in the middle indicates whether the rim is a whole.
For example: 4.50E*16 means an integral rim with a nominal width of 4.5 inches and a rim code E.
6.5-20 means a multi-piece flat-bottom wide rim with a nominal width of 6.5 inches and a nominal diameter of 20 inches.
When in use, the rim size of the car is very important. It determines which tires the car can fit on.
Tire/rim specification: international standard tire code, expressed in millimeters as a percentage of section height and aspect ratio, followed by: tire type code, rim diameter (inch), load index (allowable bearing quality code), allowable Speed code. For example: 175/70R 14 77H in 175 means the tire width is 175MM, 70 means the aspect ratio of the tire section is 70%, that is, the section height is 70% of the width, the rim diameter is 14 inches, the load index is 77, and the allowable speed is H class.