GB1459589A - Rope terminal fitting - Google Patents

Abstract

1459589 End fittting for ropes BRIDON Ltd 4 July 1975 [5 April 1974] 15136/74 Heading D1T A rope terminal fitting that can be used to couple an anchor line to an anchor contains a pyrogenic change that can be used to cause the fitting to release the anchor line from the anchor. According to the invention the fitting comprises two end parts 1, 10, Fig. 2, releasably interconnected by an intermediate part 6, the end part 1 being adapted to receive the end 3 of the anchor line, there being a cavity between the end parts 1, 10 in which a pyrogenic charge 13 is contained and which, on ignition, causes the intermediate part 6 to lose its strength and so permit the end parts to part company. In Fig. 2 the intermediate part 6 is screwed into the end parts 1, 10 to clamp a water tight casing 14 therebetween. The pyrogenic charge 13 is within the casing 14 and surrounds the intermediate part 6. The cable 3 contains electrical conductors 20, 21 coupled to a converter 19 that converts a continuous low-power input into a pulsed high-power output. The output of the converter 19 is coupled to ignition elements 27, 28 that extend into the charge 13. The converter 19 supplies either continuous pulses to raise ignition elements 27, 28 to a temperature of 1100‹C (at which the charge 13 ignites); or separate high energy pulses to ignite a primary igniter within the charge. Alternatively, the converter can be omitted if sufficient power can be transmitted along the rope 3. The fitting contains sealing rings 15, 16, 32, 33. Fig. 6 shows a modified construction in which the intermediate part comprises a plurality of spaced, parallel elongate elements 34' each encompassed by an individual pyrogenic charge 13'. The charges 13' are separated from each other by partitions 44 but are interconnected by fuses 46. In addition each charge is provided wiith its own ignition arrangement in order to ensure a fail-safe system in which (because of the interconnecting fuses) the whole pyrogenic charge will be ignited even if all but one of the ignition arrangements fail. When the pyrogenic charges ignite they reach a temperature of about 6000‹C.