Abstract: A method of injection of wire into molten steel wherein a coil of the wire is positioned around a mandrel, and the wire is pulled from the coil in the axial direction of the mandrel and is fed by transport means into the molten steel. To avoid the need to rotate the coil and yet to achieve smooth uncoiling and also to permit tow coils to be uncoiled successively without interruption the coil is a self-supporting parallel-wound coil, which is resiliently clamped around at least part of its outer surface over its whole axial length. The axial length of the mandrel is greater than that of the coil and, at the start of uncoiling of the coil there is a gap of at least 5 cm between the inside surface of the coil and the mandrel. The wire is pulled from the inside of the coil from the inside of the coil through a ring which is mounted around the mandrel axially spaced from the coil and which has a slot-shaped radial extension open to the interior of the ring.