Following its turnkey contract awardance by PPC S.A., Fulgor S.A. subcontracted Assodivers Ltd. for the installation and protection part of the electrical interconnection between the Greek islands of Kalymnos and Kos.
Two new submarine cables, with approximate length of 15,800m and 15,900m, were installed in order to support the existing electrification link. Each cable represented one campaign and both were executed on 2008. The first campaign involved the laying of the first cable, while the second campaign not only involved the laying of the second cable, but also, the protection of both.
'Argo I' DP multi purpose support vessel was used for the installation of the cables on the first campaign, while 'Astrea' was used on the second. A portable cable tank and linear machines were fixed on each vessel's deck as part of the loading, storing and laying operations.
The protection operations were executed using the DP-capable FB 'Assodiver VII', towed to/from worksites by TB 'Hydna', as a working platform to execute the landfall and nearshore protection of each cable. Due to mixed and hard soil composition, the 'AssoTrencher V' trenching vehicle equipped with a trenching wheel, along with the initial edition of 'AssoMultiTrencher' equipped with a chain cutter were used and were able to reach the required trench depth.
According to the requirements, the cables were protected at the target covered depths as described in the following table:
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Kalymnos side
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From BJ to -2m
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1,5m
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From -2m up to -15m w.d.
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1m
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From -15m up to -45m w.d.
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2m
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Kos side
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From BJ to -2m
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1,5m
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From -2m up to -10m w.d.
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1m
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From -10m up to -20m w.d.
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0.5m
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