Armouring and protections for FO

They can be either metallic or dielectric and are used to guarantee the following characteristics:

• Protection against accidental damages
• Protection against rodents
• Ballistic protection
• Moisture protection
• Protection against laying operations

In the following table are indicated the main protection types and the choice criteria.

				Tensile performance	Crush performance	Rodent protection
			Main characteristics
A1	Galvanized Steel Wire Braid Zinc plated braid. It can be used for highly flexible and mechanical resistant cables.		Rodent protection Fexibility General application
A2	Aramide Yarn Armour It consists in a layer made of aramidic yarns helically or longitudinally applied around the cable cord. This solution is adopted for totally dielectric cables, such as the aerial cables, that, besides the light weight, are characterized by high traction resistance and ballistic protection (when combined with aramidic tape).		Flexibility Dielectric Traction strength Lightweight
A3	Corrugated Steel Tape Laminated corrugated steel tape applied in a longitudinal way, close on its own and bonded to the sheath. It is applied as anti-rodent protection and as protection against cable deflection for cables that can be directly buried.		Moisture resistance Burial laying
A4	Polyamide protection This protection assures an anti-rodent and anti-termite function in dielectric cables.		Dielectric Lightweight
A5	Glass Yarn Armour Dielectric armouring in glass yarns with high traction resistance and with anti-rodent protecting function.		Flexibility Lightweight Dielectric
A6	Steel Tape Armour Steel tapes helically applied assure crush resistance and anti-rodents protection, for directly buried installation.		Compression resistance Burial laying
A7	Steel Wire Armour Zinc plated steel spiral wires. It is applied as an anti-rodent protection and/or on cables that require high tensile load.		Traction strength Burial laying
A8	Copolymer Coated Aluminium Tape It co nsists of a laminated aluminium tape applied longitudinally, closed and bonded on its own and on the sheath.		Moisture resistance
A9	HI-PACK It is a multi-layer AL/PE/Polyamide protection, used as a protection against moisture, chemical and petrochemical agents (construction as A8 with a further polyamide sheath). This is a valid alternative to lead sheath, with a lower weight and a smaller diameter.		Chemical agent protection Moisture resistance Burial laying

poor

fair

good

very good

excellent