What do you know about the bolts in your car?

Bolts used in automobiles are very important fasteners used to connect, fix and support various parts of the automobile. Bolts are usually used in conjunction with nuts to provide strong fixing force by rotating and tightening. Different types of bolts have different specifications according to their uses, materials and performance requirements. Here are some common applications and bolt types:

1. Common bolt applications in automobiles

Engine: Bolts are used to fix various parts of the engine, such as cylinder heads, engine bases, pistons, etc.

Suspension system: Used to fix vehicle suspension components, including springs, shock absorbers, wheels, etc.

Brake system: Components such as brake discs and brake calipers usually require bolts to fix.

Wheels: Bolts (or nuts) are used to firmly fix wheels to wheel hubs.

Body and chassis: Various parts of the body (such as doors, windows, hoods, etc.) and chassis frames are also connected using bolts.

2. Common types of bolts

Standard bolts: This type of bolt usually has a round head and is often used for ordinary connections.

High-strength bolts: Used for connections that withstand greater loads and pressures, usually used for important components such as suspension systems, engine brackets, etc.

Wheel bolts (wheel bolts): Bolts specially designed to fix wheels. The specifications and sizes of wheel bolts usually vary according to the vehicle type and manufacturer’s requirements.

Self-tapping bolts: Suitable for situations where pre-drilling is not required, the bolt thread can directly cut its own thread in the material.

3. Material of automobile bolts

Steel: Most automobile bolts are made of steel, and steel bolts generally need to be heat treated to increase strength.

Stainless steel: Some applications that require higher corrosion resistance use stainless steel bolts, especially those involving the exterior of the car body.

Alloy steel: For parts with high strength and high temperature resistance requirements (such as engine components, exhaust systems), alloy steel bolts may be the first choice.

4. Specifications and markings of bolts

Bolts usually have different specifications, such as diameter, length, thread type, etc. Common markings include:

M mark: Indicates the nominal diameter of the bolt (for example, M8 indicates a bolt with a diameter of 8 mm).

Strength grade marking: For example, 8.8, 10.9, 12.9, etc., indicate the strength grade of the bolt. The larger the number, the higher the strength.

5. Bolt installation and tightening

Torque control: When installing bolts, it is usually necessary to use a torque wrench to apply a specific torque force according to the manufacturer’s regulations to ensure the firmness of the connection. Overtightened or loosened bolts will affect the strength and safety of the connection.

Anti-loosening device: In some high-vibration environments, auxiliary components such as anti-loosening nuts or lock washers may be used to prevent bolts from loosening due to vibration.

6. Maintenance and inspection

It is very important to regularly check the looseness and corrosion of bolts, especially in high-load areas. If the bolts are found to be damaged or loose, they should be replaced or re-tightened in time.

Summary:

Bolts play a vital role in automobiles. They ensure the firm connection of various parts of the car and ensure the safety and stability of the vehicle. Different bolts have different materials, specifications and strength grades according to their application parts and requirements. Understanding and using bolts correctly is one of the keys to ensuring the performance and safety of the car.