Methods for impregnating a liquid material into a rope are provided whereby a liquid material is provided in a tank which defines the liquid level in the tank. An impregnation unit containing a chamber at least partially immersed in the liquid material includes a vacuum-device operatively connected to the vacuum-outlet of the chamber so as to lower the pressure in the chamber below atmospheric pressure. The rope may therefore be passed through the liquid material in the tank and then inside and outside the chamber via the rope-inlet and rope-outlet of the chamber, while maintaining the pressure inside the chamber below the atmospheric pressure to thereby force the liquid material to fill at least part of the interstices between the fibers of the rope by penetrating between the fibers.