Structural Design And Electric Field Uniformity Analysis Of Wedge-shaped Tension Clamps
In the actual operation of transmission lines, the electrical performance of the fittings directly affects the safety and stability of the line. Regarding the performance of dead end clamp overhead line at high voltage levels, industry attention often focuses on the boundary between mechanical grip strength and corona discharge. Its internal electric field distribution is a key indicator for evaluating product performance.
The wedge-shaped tension clamp's structure eliminates the possibility of potential concentration.
The product's geometry determines its electric field characteristics. The dead end clamp with eye hook uses an integral or modular cavity design, and after the internal wedge contacts the conductor, the entire clamp surface transitions smoothly. This structure avoids the sharp edges caused by the protruding screws in bolt-type clamps. The smooth transition results in a more uniform distribution of electric field lines, preventing charge accumulation at any point and thus suppressing the initiation of corona discharge. Furthermore, in terms of material selection, the aluminum alloy clamp, after T6 heat treatment, not only improves tensile strength, but its dense oxide layer also helps improve the electric field distribution.
Impact of Key Design Parameters on Electrical Performance
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Wedge Angle and Cavity Dimensions: The wedge angle tolerance of the wire clamp must be controlled within a very small range (e.g., 0.5°) to ensure a tight fit with the inner wall of the aluminum tube. This tight fit eliminates air gaps, which are weak points prone to partial discharge.
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Surface Treatment: The wire clamp, formed by solid die forging, has low surface roughness and is burr-free. Strict testing standards stipulate that the surface crack depth must be ≤0.1mm, directly eliminating the potential for point discharge caused by processing defects.
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Contact Between the Inner Cavity and the Wire: After installation, the wedge-shaped wire clamp forms a large-area contact between the wire and the inner wall of the clamp. Its gripping force can reach over 95% of the calculated breaking force of the wire. This stable mechanical connection also means reliable electrical connection; the reduced contact resistance avoids micro-discharge caused by potential fluctuations.
In summary, the dead end loop clamp maintains the uniformity of the electric field distribution and avoids the formation of sharp electrodes precisely because of its precise cavity design and smooth surface transition.
