Pylons of Cádiz
|This article does not cite any references or sources. (November 2010)|
The Pylons of Cádiz, also known as the Towers of Cádiz, are two tall pylons supporting a double-circuit 132 kV three-phase AC powerline over the bay of Cádiz, Spain starting at Puerto Real Substation at to the substation of the former Cadiz Thermal Power Station situated on the peninsula upon which the city of Cádiz stands at .
The crossing consists of 16 pylons: two 158 metres tall suspension pylons carrying the line over the Bay of Cadiz, two strainer portals built of concrete and at each strainer portal a group of 6 monopolar strainers, which are used to carry the conductors from the strainer portal to the first standard line tower ( at the northern end of the span) respectively to the switchyard of Cadiz Substation ( at the southern end of the span).
The strainer portal at the southern end is situated close to Cadiz Substation at, that of the northern end at Matagorda at . Bot strainer portals are including their upper mentioned monopolar strainers fenced-in.
The rest of the line consists of pylons with 3 crossbars carrying 6 conductors. An interesting feature is, that the powerline crossing does not use despite its great height a ground conductor in the span section.
The huge suspension towers, which are of very unconventional design, were conceived and designed by the Italian engineer, Alberto Toscano.
Each is a hollow mast resembling a truncated cone (or frustum). The diametre of the frustum decreases from 20.7 metres at the base to six metres at the top. The towers, which rest on reinforced concrete plinths carry on their pinnacle a single crossbar with rhomboid profile, on which the insulators carrying the conductors are fixed. The towers consist of galvanized steel parts, which are hold together by a network of diagonal girders. Inside the steel framework, a helical staircase ascends to the top crosspiece.
This unconventional mode of construction was chosen because Spanish steel mills were unable to produce massive steel carriers at the time, and importing such carriers was impossible because of the Francisco Franco regime.
The construction was carried out under the supervision and direction of Remo Scalla, a close friend of Alberto Toscana. The same team of Toscana, the designer, and Scalla, the builder, also joined forces in building the structures supporting the lines that span the Strait of Messina, between Calabria, on the mainland of Italy, and the island of Sicily. The Cádiz project started during the latter part of 1957 and concluded in 1960. Upon completion, the towers were acquired by the Spanish National Institute of Industry.
See also 
|Wikimedia Commons has media related to: Pylons of Cádiz|
- High Voltage Masts to Cadiz Island at Structurae
- Google Maps: Matagorda Pylon (Pylon on Mainland)
- Google Maps: Puntales Pylon (Pylon at Cadiz)
- Panoramio: picture.
- A set on Flickr.