As we have seen earlier, regular checking of the plasma torch’s consumables and replacement is very important. At the same time, regular checking and maintenance of the plasma torch is also vital to the cut quality. Let us look at some of the common plasma torch mistakes that one can make and must take care of.
Incorrect Torch Assembly
The plasma torch must be assembled properly so that all the parts are aligned properly and fit securely. The correct fit ensures that there is proper electrical contact and the flow of the gas, as well as the coolant, through the plasma torch is fine.
Maintaining cleanliness during the assembly of the torch is very important. You must ensure that the consumables are placed on a clean surface or cloth so that the torch is not contaminated by the metal dust or dirt when changing the parts. Use O-ring lube sparingly as too much lubrication can result in the clogging of the swirl ring and the torch can be contaminated with metal dust. This may result in the arc becoming uncontrolled in the plasma chamber and ultimately cause the plasma torch to fail. You should not apply any grease to the plasma torch as this can cause uncontrolled arcing and burning inside the torch.
Routine Maintenance Neglected
With proper maintenance and care, plasma torches can last for years. You must ensure that the torch threads are clean and the seating areas are not contaminated or damaged. You must clean any metal dust, dirt or O-ring lubricant from the torch. Use a cotton swab dipped in hydrogen peroxide or electrical contact cleaner to clean the plasma torch.
Crashing the Plasma Torch
Crashes can damage your plasma torch irreparably. To prevent the torch from colliding with the workpiece, you can program the cutting system to travel around the cut parts rather than over them. By correcting the variations in the material, torch height sensors can also protect from torch crashes. However, torch height controls (THC) that are voltage regulated may not be able to protect the torch adequately. To minimize this, you must carefully program the THC function and the lead out. Also, mounting devices can help to prevent any damage to the plasma torch if a collision occurs.
Not Checking the Gas and Coolant Flow
The pressure and flow of the gas and the coolant in the plasma torch must be checked every day. The parts will not be cooled properly and their life will be considerably reduced if the flow is not adequate. Worn out pumps, low coolant levels and clogged filters are some of the reasons for the insufficient flow of cooling water that can cause the plasma torch and consumables to fail.
To maintain the cutting arc, a constant gas pressure is important. Hard starting is caused due to excessive gas pressure when the torch fails to start an arc. Excessive gas pressure also causes the electrodes to wear out quickly. Usually, compressed air systems are vulnerable to moisture, particle and oil contamination. Plasma gas should also be kept clean to prevent short torch and consumable life.
Regular care and maintenance of all the consumables and plasma torch is essential for the plasma cutting system to work at its highest efficiency and produce high-precision and high-quality cuts.