Abstract: A method of packing elongated porous bodies moved between zones of different pressure, wherein the porous body (T) reciprocates through a pressurized packing agent (M). The packing agent is thixotropic and is supplied continuously to the porous cable (T) under a pressure exceeding the pressure in a higher pressure zone (P.sub.1) while the porous body (T) is impregnated with a thixotropic packing agent (M) such that the cross-section of the cable, throughout its entire length, is filled with packing agent (M). A hydraulic cylinder-type actuator utilizes a porous cable power transmission element packed in a chamber (7) filled with viscoelastoplastic material and communicated with means designed to develop in said chamber a pressure exceeding the pressure of the actuator working fluid.

Abstract: A hoisting apparatus comprising a hydraulic cylinder (1) a piston (3) whereof is connected to a load-handling attachment via a pliable member (6) which passes through a sealing device (9) that is located outside the cylinder (1) and consists of two consecutively arranged chambers (10, 11) separated by seals (12, 13, 14). The chamber (10) next to the cylinder space is filled with a sealing fluid whose viscosity is higher than the viscosity of the hydraulic fluid and the other chamber (11) is connected to a separator (18) adapted to separate the hydraulic fluid from the sealing fluid and to feed them to the space (4) of the hydraulic cylinder and the chamber (10) of the sealing device (9), respectively.