Method and apparatus for laying an oil filled cable at depths below the laying equipment

摘要

Method and apparatus for laying an oil filled, electric cable at great depths and under conditions whereby the weight of the oil may cause internal cable pressures which will rupture the cable. In the method, the leading cable end is fed over a guide which is higher than the point at which the weight of the oil column between the guide and the cable source is equal to the normal oil pressure in the cable and is then fed downwardly but without exceeding an amount which would cause the oil column pressure after the guide to exceed safe limits for the cable. The pressure on the oil at the cable source is then reduced producing a torricellian vacuum in the cable at or near the guide which is maintained at a value such that the weight of the oil in the vertical section of the cable does not exceed safe limits. The apparatus includes the guide and pressure regulating and indicating devices at the cable oil source and the leading end of the cable.