Method and device for installing a cable in a cable duct

Abstract

The invention relates to a method, a device and a method for installing a cable in a tubular cable duct. In the method, the foremost end (3) of the cable (1) in the duct (10) and subsequent portions of the cable are first accelerated in a short time with continuous supply of further portions of cable from a torsion-free store. Then, from the instant a certain speed v is reached, the cable is maintained at a tension such that, at said speed and tension, centrifugal forces in bends and inwardly pulling components of tensioning forces in the cable compensate for one another at the position of said bends, the further portions of the cable being supplied at a supply speed such that the part of the cable already fed into the duct can continue to slide on the basis of its mass moment of inertia. The acceleration can be achieved by causing propelling forces to act on the cable upstream of the inlet end (10a) of the duct in conjunction with pulling forces which act at least on the foremost end (3) of the cable (1) in the duct. The magnitude of at least the propelling forces is controlled by adjusting to zero the net transverse force on the cable, in a bend (8; 51) in the cable located beyond the position where the propelling forces act upon the cable in the direction of movement of the cable. Advantages are that much higher installation speeds and/or greater installation lengths in one go are possible.