Understanding Bolts and Clamps for Lattice Steel Tower

The safety and dependability of lattice transmission towers (LTTs) and line systems are crucial in modern cultures. Failure of the LTT system might have significant economic and societal ramifications. 

Aside from the direct costs of asset damage, post-disaster interruptions could result in significant indirect losses and serious consequences. Due to rising corporate and domestic power demand, understanding its parts would be crucial. 

If you want to learn more about its parts, specifically its bolts and clamps, and how angular steel towers manufacturer can help you then read on through this article.


Bolted-together clamps must have breakaway heads or covers and good washers. The fasteners must be lubricated with an appropriate lubricant. The clamps must be designed to fit securely and effortlessly on the conductor while applying sufficient pressure to account for creep, cold flow, and/or nesting. 

Arm Clamp

The arm attachment must be fabricated from an aluminum alloy that satisfies the design specifications. The clamp cover must also be composed of aluminum alloy.

The arm clamp and clamp cap must have a bearing length of at least 70 mm on the conductor for clamps for metal surfaces. To meet this criterion, evacuation radii must be eliminated.

Bolted Type

When mounted on the conductor, bolted-type spacer assembly clamps must sustain a torque equal to double the nominal design installation torque without part failure. To acquire this figure, apply the torque to the lower head of the breakaway bolt or cap screw.

With a breakaway shear head bolt or breakaway cap screw for galvanized steel bolts, clamping bolts must be at least M12 stainless steel or M16 aluminum alloy. They must also have a wrenching stop to prevent the socket from engaging the lower head during installation.

The torque required to separate the upper head from the lower head must fall within a 10% tolerance of the Supplier-provided design value.

The steel Belleville-type spring washers on clamping bolts or cap screws must have a recoverable deflection of at least 0.9 mm, as measured by the difference between the loaded and unloaded heights. These washers are meant to compensate for potential fastener tension relaxation. The Supplier may use two Belleville washers to regulate clamp fastener loosening.


Bolts must only be made to withstand shear and bearing pressures, and all bolts—aside from U-bolts—must have shanks that extend entirely through all connected members. When installed, bolts must extend no less than two thread lengths and no more than ten millimeters through the matching fasteners. 

Members are not allowed to comment on threads. There must be washers under every fastener. The heads of the bolts must be concentric with the shank and free from fins, rust, and other flaws. The bolt shank’s diameter must match its specified size exactly. The extremities ought to be tidy and have the right shape.

All U-bolts must have threads long enough to fit two standard nuts and the member and gasket thicknesses.


The nuts must be tall enough to provide the full strength of the bolt. Threads must be in good condition and not torn or ragged. The nuts must fit the galvanized bolts such that the entire length of the bolt thread can be started and threaded by hand. There must be no swaying of the nut due to the manner the nut is fitted to the bolt.

Bolts and nuts of the same size must be interchangeable. For manufacturing purposes, bolt dimensions are found in DIN 7990, and nut dimensions are available in DIN 555/ISO4034. One spring washer’s thickness must be considered when estimating bolt lengths.


Understanding the importance of bolts and clamps in lattice steel tower systems is crucial for ensuring the safety and reliability of transmission and line systems. Adhering to these guidelines and specifications ensures the reliability and stability of lattice steel tower systems, reducing the risk of failure and the potential for significant disruptions. By understanding the importance of bolts and clamps and their proper installation, we can contribute to these critical infrastructure elements’ overall safety and dependability.

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