Abstract: A method and apparatus for equalizing the tension of optical fibers to a predetermined value, in which optical fibers (3) are passed from starting reels (1) through an equalizer wheel structure (4) to the next stage of the process. The equalizer wheel structure (4) is formed by two wheels (5, 6) on which the fibers (3) travel in succession. The first wheel (5) is adapted to supply fiber to the second wheel (6) at a greater rate than that which passes on the second wheel and is supplied to the next stage.

Abstract: A method and arrangement for producing a basic element of a multi-element fibre optic cable having a coating tool (6) for forming a tubular sheathing around a single optical fibre (3) or a fibre bundle formed of several optical fibres (3), and a pulling device (8) placed after the coating tool (6) for pulling the sheathing and the fibres forward as a unit. In order to produce a stable product, the tension (t.sub.3) of the fibres (3) passed to the coating tool (6) is kept continuously at a controlled level. The direction of travel of the fibres and the sheathing is kept straight before and at the pulling device (8), and the pulling device (8) is spaced from the coating tool (6) at a distance depending on the production rate of the production line, so that desired sliding of the fibres (30 inside the sheathing is provided at the pulling device (8).

Abstract: A method of producing an optical multi-fibre cable element provided with a secondary sheathing by extruding (1) a loose secondary sheathing (10) around a fibre bundle (9) and providing the fibres with a desired extra length with respect to the secondary sheathing. To avoid variation in fibre length in the production of cable elements the secondary sheathing (10) together with the fibre bundle (9) is twisted (12) around its axis after the extrusion step (1) at least to such an extent that the longitudinal sliding of the fibres with respect to each other is prevented in the twisted fibre bundle and that the stretching of the fibres in the fibre bundle at the step of providing the extra length (3; 18) is kept within the elastic range of the fibres.

Abstract: A method and apparatus for producing an optical multi-fiber cable element provided with a second sheathing by extruding a loose secondary sheathing around a fiber bundle and stretching the fibers a desired extra length with respect to the sheathing, the fibers being guided in such a manner that the position of the fibers varies continuously during stretching. To produce an untwisted cable element and avoid variation in the fiber length, the secondary sheathing together with its fiber bundle is twisted around its axis after the extrusion or the sheathing to vary the twisting position of the fiber bundle as the sheathing and fibers approach the stretching step.