An anchor portal or H-frame tower is a gantry structure supporting overhead power lines in a switchyard. Their static function is similar to a dead-end tower. Anchor portals are almost always steel-tube or steel-framework constructions.
Gallery
A simple H-frame anchor tower consisting of two poles and one horizontal crossarm, bearing similarity to the letter H
anchor pylon and anchor portal, 380kV
anchor gantry, 110kV
diagonal frame
Multi-level gantry tower
Gantry tower with road underneath
References
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