Due to the high loads automotive wheel must be firmly fixed on the axle, but free to rotate and to transmit movement of the suspension. Answer for this wheel. Let us look at the device, the purpose, structural characteristics and maintenance of this functional element.
What is a hub?
Detail is one of the main structural components of automobile suspension. It provides connection of all the parts of the wheel together.
The wheel hubs give the opportunity to repair and maintenance of suspension with only partial replacement of some elements. In the absence of the hubs of the wheel would be molded, solid construction. As a result of the failure of a disk, drum or the bearing would require replacement of the entire structure. Wheel allow you to quickly eliminate the defects of the parts, to remove and quick to install the new one.
The presence of the hub is reflected in the steering, suspension, brake system. The part is subject to significant mechanical loads.
This element of the vehicle chassis performs the following tasks:
- Is a means to hold the rim.
- Serves as the basis for fixing brake disc and drum.
- Allows the wheel to rotate freely.
- Keeps the structural part of the ABS, the nodes of the axle shaft.
The device of the wheel depends largely on the type of vehicle. Since the hub are a significant load, make it of cast steel billet, and then shape the technique of turning and milling. The appearance of a part is known to every motorist. The design includes a rounded rim with an inner bore of a complex configuration under the axle and rim of the openings for fasteners.
The standard hub is a hollow short cylinder, the outer surface of which contains a flange that serves as a basis for fixing the wheel and brake discs. In the hubs of the wheels have slots and the undercut under the bearing, which facilitates smooth installation into the knuckle of the chassis. In vehicles with a rear drive type, the element is usually connected to the axle shaft where the bearings zapressovyvajutsja.
With regard to freight transport hubs, they are often combined with the brake drums. Such a solution allows to significantly facilitate the maintenance and repair of the locking mechanism part.
The wheel hub bearing
The functional element is mounted on angular contact ball or tapered roller bearings. The latter are characterized by a greater carrying capacity. This is due to the formation of linear contact area with treadmills, whereas the ball bearings create less area of contact with the surfaces.
The widest spread on cars purchased angular contact ball design. During Assembly, the bearings of this plan are covered by long-lasting lubricant is firmly mounted in the hub, and therefore do not require regular maintenance.
Replacement wheel hub
When operating in normal conditions, the hub needs to be replaced only if the relief the landing of the bearing or deterioration of ability of the outer race to a strong hold of the wheel. Also, the hub of the rear wheel may require removal in case of wear of the threaded connections studs and bolts.
The work is done in stages:
- Car jacked up, removed wheels.
- Vivenciada fasteners that hold the brake caliper.
- Removed the Central nut, the brake rotor removed from hub.
- The end of the drive shaft is weakened, after which it is knocked out by about 10-15 mm with a copper or rubber mallet.
- Removed the screw spindle of the wheel.
- Steering knuckle, Unscrew the fastener from the a-pillar.
- Removed the steering lever, then the drive shaft.
- Install the new hub of the rear wheel or the front and is fastened with new bolts, which are included in the repair kit.
- The screws are tightened diagonally, mounting of all components in the reverse order.
Operation as the chassis of the car is mainly exposed to wear bearings. Often there are various faults and defects in the cast part of the hub. So the bearings, seals, and in some cases the hubs need servicing and replacement. If needed, prompt the emergence of increased backlash wheels and all sorts of knocks during the movement of the vehicle.
In general, the hubs are extremely reliable and durable element of the chassis of the car. With careful operation and timely service, this item does not cause problems for the motorist for many years.