SCHEDA TECNICA. Amarro per cavi 13,5mm Amarro per cavi 16,5mm. MS217F00 Amarro per cavi 13,5mm MS218F00 Amarro per cavi 16,5mm

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1 SCHEDA TECNICA Amarro per cavi 13,5mm Amarro per cavi 16,5mm Material: Galvanized steel MS217F00 Amarro per cavi 13,5mm MS218F00 Amarro per cavi 16,5mm

2 For cable 13,5mm For cable 16,5mm

3 3. Weight The weight of amarre for cable 13,5mm (MS217F00) is around 0,340kg. The weight of amarre for cable 16,5mm (MS218F00) is around 0,370kg. 4. Processing 4.1 Aspect The dimensional characteristics of the Amarro are defined on the drawing. The product must not show cracks, flakes, inclusions, incomplete parts, straws, pores, distortions, fractures, rifling, burner and any other defects that can damage the functionality. The Amarro must be complete and uniformly galvanized. 5. Test 5.1 Material The material of the Amarro shall be galvanized steel. 5.2 Visual inspection The Amarro shall be free of defects and other possible deformities. 5.3 Dimensional inspection The correct dimensions according to drawings at pag. 4 must be verified. 5.4 Functional test Sliding test The purpose of the test is to verify the absence of slip between amarre and cable, when it is under strain. The test should be performed on a section of suitable length of cable (10 15m) which results medium of a 1km line length. At one end of the treatment chosen is applied the amarre, signing with two markers, its position relative to the cable sheath and the other ends of the cable is fixed with a suitable anchorage. The system cable + amarre is put under strain (500N/min speed) with a increased load equal to 105% of maximum working draft (TME) for optical self-supporting cable (270kg), then the load is reduced to 100% of TME and held for an hour.

4 Subsequently, the load is again increased to 210% of TME, and decreased to 200% and held for an hour. For tests at low temperature (T = -30 C) and hot temperature (T = +60 C) the head of shot (cable + amarre) should be enclosed in a suitable thermal camera, to maintain the temperature required during the test. The thermal camera should have a length at least twice length of the amarre. The shot must be maintained for a period of at least one hour, during which must remain constant. The test is performed with the following temperature: +20 C, -30 C, +60 C. Corresponding to the pitches indicated, sliding between cable and amarre must be zero, and verifying the integrity of the marking. During the test, the fibers must be monitored (example: 1 for cavity) by OTDR, with a pulse of 100ns (IEC ) Wind vibration Purpose of test is the check of the behaviour of system amarre + cable + suspension clamp when subjected to wind vibration; the equipment is schematically represented in figure below. At the end of a section of cable of suitable length (minimum 30 m), which is intermediate to 1 km line length, are applied two amarre (4). In order to have repeatable results is necessary that the active span is at least 20 m and the total stretch is at least 30 m with suspension placed in 2 / 3 of span (6). At the end of the line, the optical fibres must be fixed properly to prevent movements on the cable. The tensile force is measured with a dynamometer (2) and the cable is subjected to a constant voltage of 90kg. The angle of the active span with the horizontal line must be between 1 and 2. The vibrator (5) must be used to vibrate the wire in the vertical plane at a frequency close as possible to the resonance frequency corresponding to a wind speed of 5 m/s, this frequency must be calculated using the following formula: where d is the outer diameter of the cable expressed in mm and V is wind speed in m / s. The peak-peak amplitude of oscillation will be equal to 0.5 d. The vibrator is placed to have at least six complete oscillations of the suspension clamp and the vibrator itself. The cable must be subjected to cycles by monitoring the amplitude of antinodo oscillation. During the test must be monitored the optical power and will not detect increases of attenuation according to IEC

5 5.4.3 Creep test (plastic expantion) The purpose of the test is to verify the reliability of the cable + amarre over time. The test should be performed on two lengths of cable longth m. At one end is applied the amarre, at the other end the cable is fixed with a suitable anchorage. The two systems cable + amarre must be preloaded (speed 500N/min) to 270kg and subsequently discharged. After this operation, the two systems must be put under (a) test and (b) test. Test (a): The system cable + amarre is subjected and maintained at a load of 270kg (Speed 500N/min) for 1000 hours, monitoring the change in extension of the system. Test (b): The system cable + amarre is put under a load of 90kg (speed 500N/min), than keeping constant the extension is estimated the decrease of the load in a time of 1000 hours. For tests at low temperature (T = -30 C) and hot temperature (T = +60 C) the head of shot (cable + amarre) should be enclosed in a suitable thermal camera, to maintain the temperature required during the test. The test is performed with the following temperature: +20 C, -30 C, +60 C (by time for tests A and B). The values of extension [test (a)] and load [test (b)] measured must reach the asymptote before 1000 hours of tests at all temperatures provided. 5.5 Resistance to atmospheric and chemical agents Salt spray The amarre must be exposed in appropriate salt spray chamber according to ISO 9227, NSS method for 720 hours. At the end of the test the amarre will be put through sliding test (see 5.4.1) Acid solution The amarre must be immersed in H 2 SO 4 (PH ~ 5) solution for 720 hours. After the test, the amarre will be put through sliding test (see 5.4.1).