Broken wire associated with molybdenum wire

1. Tension and wire speed

1) Increasing the tension of molybdenum wire can reduce the influence of wire vibration, so as to improve the precision and cutting speed, and significantly reduce the broken wire. It is generally considered that the tension is more appropriate at 12-15n.

2) The increase of wire walking speed is conducive to the molybdenum wire to bring the working liquid into the discharge gap of the workpiece with a large thickness, so as to ensure the elimination of electrical corrosion products and the stability of discharge processing. However, if the wire speed is too high and the molybdenum wire is shaken seriously, the machining stability will be damaged, the machining accuracy and surface roughness will become worse, and the wire will be easily broken. When the wire speed is too low, it is easy to break the wire due to large loss. Generally, it is advisable to be less than 10m/s.

A broken wire associated with a guide wire structure

1. Wire breaking related to the wire transport barrel

1) The inner and outer circles of the wire transport cylinder are not coaxial, resulting in unbalanced inertia. During operation, it is easy to produce overlapping wires and lead to broken wires.

2) The shaft and bearing of the wire transport cylinder often have gaps due to wear and tear, which is easy to cause the silk jitter and break.

3) If the high frequency power supply is not cut off during the reversing of the wire transport barrel, the molybdenum wire will be burned due to the high temperature in a short time. Therefore, it is necessary to check whether the travel switch at the rear end of the wire transport barrel is out of order (whether the relay controlling high frequency is damaged).

4) Maintain the flexible rotation of the wire tube and guide wheel, or the wire system will break due to the vibration of the guide wire system during the round trip operation.

5) The limit block at the rear end of the good-luck reel shall be adjusted to avoid the breaking of the thread when the reel breaks out of the limit stroke.

6) Stop the machine shortly after reversing to prevent the wire transport cylinder from damaging the transmission parts and pulling the molybdenum wire due to the inertia ultrashine.

2. Broken wires related to guide wheel and conductive block

1) If the guide wheel and the conductive block have grooves due to wear, or if the guide wheel bearing has gaps due to wear, it is easy to cause the molybdenum wire jitter and broken wire.

2) The molybdenum wire shall be in good contact with the conductive block, the processed workpiece and the working surface, otherwise the negative electrode of the high-frequency power supply cannot be connected with the molybdenum wire or bad contact will be caused.