We all know that bolts are called the rice of industry. Do you know the classification of commonly used transmission tower bolts? Generally speaking, transmission tower bolts are mainly classified according to their shape, strength level, surface treatment, connection purpose, material, etc.

Head shape:

According to the shape of the bolt head, the commonly used transmission tower bolts are mainly hexagonal head bolts.

Surface treatment method:

Since common transmission tower bolts such as steel pipe towers and angle steel towers are hot-dip galvanized to meet performance requirements such as impact resistance and corrosion resistance, they are classified as hot-dip galvanized transmission tower bolts.

Among them, anchor bolts are important connecting components to ensure the safety of electricity pylons. Their surface treatment methods include partial hot-dip galvanizing and comprehensive hot-dip galvanizing for the threaded part.

Level strength:

Transmission tower bolts are divided into four grades: 4.8J, 6.8J, 8.8J and 10.9J, among which 6.8J and 8.8J bolts are the most commonly used.

Connection purpose:

Divided into ordinary connections and embedded connections. Anchor bolts are embedded parts of electric power transmission tower， and are usually used to fix the tower base to ensure stable support for the tower base’s own weight and external loads.

Since they need to be firmly connected to the concrete and prevent them from being pulled out, the types of embedded anchor bolts for transmission towers include L-type, J-type, T-type, I-type, etc.

Different types of embedded anchor bolts have different thread specifications, sizes and performance levels, and should comply with the DL/T1236-2021 standard.

Material:

Materials include Q235B, 45#, 35K, 40Cr, etc. For example, the 6.8J power transmission bolts of M12-M22 specifications are commonly made of 35K materials and do not require modulation, while the commonly used materials of M24-M68 specifications are made of 45# materials and do not require modulation.

The 8.8J power transmission bolts of M12-M22 specifications are commonly made of 35K, 45#, and 40Cr materials and need to be modulated. The commonly used 45# and 40Cr materials of M24-M68 specifications need to be modulated. The specific material requirements for transmission tower bolts and nuts should comply with the DL/T 248-2021 standard.