A very important aspect of any manufacturing or fabrication unit is to improve the efficiency and working of the shop floor. Speaking of a CNC plasma cutting unit, the objective of the process is to get high-quality parts efficiently and quickly. For this, it is very important that the material handling processes, the CAM nesting software used, the plasma cutting system, the motion controls, all of these must be reliable, competent and of top-quality.
Often, in any plasma cutting operation, the consumables, which are most critical to the operation, such as the plasma torch, the electrode, nozzle, swirl rings, retaining caps and the shield, are the most neglected components. And, very often, when you visit a shop floor, you can see plenty of these worn out, discarded parts by the bucketful. The condition of these discarded consumables can tell you a lot about the way the cutting operation is being managed.
Several times, you may notice that around 40% of the so-called “used consumables” are not really worn out and can actually be reused to produce great cut quality. Also, various things such as the swirl marks on the nozzle, the condition of the orifice, the nozzle itself and the erosion of the electrode can be an indication of the condition of the plasma cutting system or if your machine operators need to be trained on proper consumable use.
Using the consumables until they are completely worn out can help in huge cost savings for your business. Ideally, the consumable parts’ cost should not be more than 10% of the operating cost. However, in most of the manufacturing operations, this number is closer to around 25% or more.
Advancements in plasma cutting technology have, to a large extent, improved cut quality, consumable cost and hence the operating cost of a plasma cutting system. However, the responsibility of getting the most out of the plasma cutting system and the consumables, falls on the operator of the plasma system.
The fabrication unit must have specific rules about when the consumable parts must be replaced, otherwise, this decision is left to the whims and fancies of the machine operator. Usually, some consumables may require to be changed once every shift, some can easily go on for around more than 50 shifts.
The frequency of consumable change depends on several factors such as the material thickness and type, the amount of cutting that is done per shift, the amperage used for cutting, etc. Hence, it is very important that the plasma system operator understands how each consumable part functions, should be able to understand and recognise the patterns of wear, when the parts can be reused and when to replace them. This kind of training for operators can result in a reduction of consumable parts usage by around 40%.
Ways to Optimise Consumable Part Life
Ensure that your CNC plasma cutting system has the latest technology and components such as the latest CAD/CAM software, power supply, THC (torch height control), etc. This will help you get the best in terms of the cut speed, cut quality and long consumable life.
The second aspect is to ensure that your plasma cutting system is maintained properly as per the manufacturer’s guidelines. If maintained properly, your cutting system can last you for a very long time and give you efficient service.
Ensure that your system operators are trained in consumable part optimisation and that they are able to inspect the consumables properly.
And finally, you must ensure that the consumable parts are not run till they finally fail. This can lead to the catastrophic failure of the electrode, the nozzle, shield and finally the plasma torch itself. Proper education of the plasma machine operators and optimal use of consumables can help to ensure significant cost savings and increased productivity of your plasma cutting business.