To take a wire cut into pieces out of a machine in a short time without detaching a water jacket by providing a wire jumping preventing guide to be extended in a clearance in the tip of a wire guide part.

A cylindrical wire jumping preventive guide 11 is attached to a water jacket 7 by four bolts 12. For example, when the minimum diameter of a passing wire is 5.0 mm, the length of the guide 11 is set to be 18 mm so that the clearance A between a J pipe 10 and the wire jumping preventive guide 11 is 3 mm. When the wire is cut into pieces while a wire ring forming device is in operation, the tip of the wire cut into pieces in forming the wire of 5.0 mm in diameter is left behind the inside of the wire jumping preventive guide 11, and the cut wire can be taken out only by detaching parts 1-5. Thus, the time required from taking out the cut wire to the repair can be shortened fro the conventional value of 120 minutes to 30 minutes, and the line stop time can be greatly shortened.