Detailed Explanation Of The Influencing Factors On The Frictional Self-locking Performance And Structure Of Pre-twisted Wires

In the construction of power transmission lines, armour rod exhibits stability in the friction self-locking process due to its unique structure. There is a microscopic contact surface between the surface of armour rod in transmission line and the wire core, which achieves a self-locking state through friction, so that the structure remains fixed under the action of external force. The formation of friction self-locking depends on the spiral winding method of armor rods conductor and the material properties. The frictional force is distributed between different layers, which has a direct impact on the overall stability.

Structural Characteristics of Frictional Self-Locking

The multi-strand structure of the pre-twisted wire forms multiple contact points, and the close arrangement of each strand contributes to frictional self-locking. Structural characteristics can be divided into three aspects:

• Helix Angle: Affects the pressure distribution on the contact surface; changes in the helix angle alter the magnitude of the frictional force.

• Wire Diameter Uniformity: A uniform wire diameter maintains the continuity of frictional self-locking; irregular diameters may lead to localized stress concentration.

• Surface Roughness: Surface roughness directly relates to the coefficient of friction; microscopic irregularities have a significant effect on the self-locking effect.

These details reveal the complexity of pre-twisted wire frictional self-locking; each factor has its physical role and path of action within the overall structure.

Analysis of Frictional Self-Locking Performance

Under current conditions, the frictional self-locking characteristics of pre-twisted wires can be quantified through tensile and creep tests. By measuring the relative slippage under different loads, the variation of frictional force with load can be observed.

The frictional force between the helical layers increases linearly, and when a certain load threshold is exceeded, frictional self-locking can still maintain structural stability. This performance is closely related to the material selection and stranding process of the pre-twisted wire, providing a quantifiable reference for the frictional self-locking mechanism.