Reasons for the instability of CNC plasma cutting machine

1. Unstable arc

The CNC plasma cutting machine uses a high-frequency oscillator to excite the gas between the electrode and the inner wall of the nozzle, generating high-frequency discharge. The negative gas is partially ionized to form a small arc, and under the action of compressed air, it is ejected from the nozzle to ignite the plasma arc. This series of processes are all completed by the spark generator. If the spark generator cannot automatically break the arc, it is usually caused by the maladjustment of the control circuit board components or the inappropriate gap between the discharge electrodes of the spark generator. Therefore, the spark generator discharge electrode should be checked regularly and the gap between the discharge electrodes of the spark generator should be adjusted in time.

2. Unstable AC voltage

The failure of the main circuit components inside the CNC plasma cutting machine is one of the reasons for the unstable input AC voltage. The damage to the circuit components is mainly caused by the accumulation of dust in the controller during the cutting process, so the operator should clean the controller regularly. In addition, because the plasma cutting machine consumes a lot of power when in use, if it is operated together with large electrical equipment at the same time, it is very likely to cause unstable power supply voltage and affect the stability of the plasma arc.

3. Insufficient air pressure stability

If the working air pressure is too low, the ejection speed of the CNC plasma cutting machine will be reduced, and a high-energy, high-speed plasma cutting machine cannot be formed, resulting in poor incision quality, incomplete cutting, and incision accumulation. If the working air pressure is too high, the excessive airflow will disperse the energy of the arc column and weaken the cutting strength of the CNC plasma cutting machine. Therefore, during the cutting process, a suitable air pressure value should be selected, preferably consistent with the air pressure value required in the instruction manual, so as not to affect the cutting accuracy.

4. Poor ground contact

Grounding is an essential preparatory work before cutting. It not only affects the cutting quality but also the personal safety of the operator. Grounding should be equipped with special grounding tools, and the ground wire that is severely aged due to long-term use should be eliminated to avoid poor contact between the ground wire and the workpiece and affect the stability of the CNC plasma cutting machine.

5. Damage to the cutting nozzle and electrode

During the cutting process, the torch nozzle and electrode are burned, which will not only increase the cost of use, but also cause the instability of the CNC plasma cutting machine. When replacing the cutting machine, check whether the cutting machine nozzle is installed as required, and regularly maintain and repair the cutting torch nozzle and electrode.

Solutions to the instability of CNC plasma cutting machine

1. Check the gas circuit to see if the gas supply is stable.

2. Check the plasma consumable parts to see if the consumable parts of the CNC plasma cutting machine are intact. Are you using a replacement or the original one?

3. If the above two problems are all good, check whether your plasma grounding is firm. If you start the arc in the air every time, the cutting gun has an arc light, and generally there is no problem with the plasma power supply itself.

4. If the above 3 points are all good, then check the feedback signal line of the CNC plasma cutting machine, which may have poor contact.