In the CNC plasma cutter, the consumable parts that are generally considered include electrodes, nozzles, swirl rings, and protective caps. They each play an important role in plasma cutting. Increasing the service life of the wearing parts of the CNC plasma cutter can reduce the operating cost of the machine, so how should the service life of the wearing parts be extended?
Factors affecting the life of consumable parts of CNC plasma cutter
In a normally operating system, several key factors affect the life of consumable parts, the number of perforations, material thickness, cutting current, cutting speed, cutting height, and perforation height. Changes in these parameters will bring changes to the life of consumable parts, as shown in the figure. It can be seen from the figure that when the number of perforations increases, the life of the consumable parts will be shortened. When the thickness of the cut steel plate increases, the life of the consumable parts will be shortened. When the cutting current increases, the life of the consumable parts will be shortened. The cutting speed will be too fast or too high. Slow, too low or too high cutting height, too low or too high perforation height, will greatly reduce the service life of wearing parts. Also, poor cutting processes will cause changes in the above parameters, thereby shortening the life of consumable parts. The mismatch between the material and cutting thickness of the cutting material and the consumable parts will also affect the life of the consumable parts. The quality and flow of plasma cutting gas also affect the life of consumable parts. When the equipment is operating abnormally, such as the plasma gas pressure is too low, the coolant flow rate is too low, the gas system is leaking, the gas system is squeezed or twisted, the filter element blocks the gas path, and the cooling cycle temperature is too high or too low. Shorten the life of consumable parts. The important role of consumable parts in plasma cutting determines the technical requirements for consumable parts, and the quality of consumable parts themselves also determines the service life of consumable parts.
Methods to improve the service life of consumable parts of CNC plasma cutter
Due to the many factors that affect the life of consumable parts, the uneven experience of operators, and the very different methods of enterprise equipment management, the cost of consumable parts in the current use of plasma cutting machines varies greatly among enterprises. According to our research and long-term user tracking feedback, the following methods can generally improve the life of consumable parts without affecting the cutting quality and production capacity.
1. Correct selection and installation of consumables
According to the instructions in the operation manual, select the correct consumables according to the cutting current, materials, etc. It is strictly forbidden to use the consumables with the low cutting current for high current cutting. Any misuse will affect the life of the consumables. Use clean hands and use special tools to install the clean wearing parts in the clean torch body. Do not over-tighten. Do not over-apply grease when lubricating with grease. The vortex ring is a fragile item, so be careful when removing and installing it. Before installation, check carefully whether there are cracks and missing, whether all the inner and outer O-rings are broken or flattened, whether there is blockage or excessive grease in the vortex hole. Before the protective cap is installed on the cutting torch, a small amount of welding slag spatter spray can be sprayed on the outer surface of the protective cap, which helps reduce the risk of spatter accumulating on the protective cap and damaging the protective cap. When replacing a wearing part, keep the other unreplaced wearing parts clean, and remove the slag sticking to the wearing parts in time.
2. Choose appropriate cutting parameters and cutting process
The selection of cutting parameters directly affects the life of consumable parts. For example, setting the perforation height too low will cause slag to be returned to the cutting torch. If the perforation height is too high, it will cause too many pilot arcs and cause excessive nozzle damage. Different materials and thicknesses have different perforation heights. Setting a proper perforation height will reduce the damage of consumable parts and torch. When cutting plates of different materials and thicknesses, the cutting parameters should try to choose the cutting characteristic parameters provided by the equipment manufacturer. A good cutting process is essential to extend the life of consumable parts. For example, when cutting a small round hole, the cutting lead-out line at the end of the round hole in the program is often before the "gradual drop" of the cutting arc. Due to the falling of the material, the cutting arc has separated from the steel plate, which seriously affects the service life of the electrode. It is recommended that there is no cutting lead-out line in the program or the overburning length is set in the program or the appropriate negative cutting stop time is set to reduce this phenomenon. Try to cut from the edge as much as possible, and do not start arcing in the air. At the end of each cutting operation, ensure that the cutting arc remains on the workpiece to avoid sudden extinguishment of the cutting arc. When nesting on a steel plate, try to cut the parts continuously to reduce the number of perforations to reduce the damage of consumable parts.
3. Replace damaged consumables in time
Workers on-site often fail to replace the damaged consumables in time to catch up with the schedule or cost considerations during operation. In fact, failure to replace the damaged consumables in time will cause worse consequences, such as excessive use of damaged electrodes, which will lead to Accelerated damage of nozzles, protective caps, and water pipes that can even cause damage to the cutting torch and decrease in cutting quality. The price of the cutting torch and the protective cap is much higher than that of the electrode. The loss of other more expensive parts is more than the loss due to the reduction of the number of replacement of the damaged electrode and nozzle. It is recommended that the electrode and the nozzle be replaced in pairs, and the vortex ring should be replaced according to the actual use. The protective cap should be replaced when the physical wear or the cutting quality decreases.
4. Choose the right gas, pressure, and flow
Different cutting materials and different cutting power sources should use different plasma gas and protective gas. Before use, check the manual provided by the equipment manufacturer to select the correct gas. Gas quality problems such as gas impurities, dampness, dirt, and contaminants in the piping system will reduce the service life of consumable parts, so keep the plasma gas clean and dry. To ensure the quality of the gas, after replacing the wearing parts, it is best to purge for one or two minutes before cutting. When it is found that the air pressure and flow rate are low, check whether there is leakage in the gas circuit and joints, whether the gas is blocked, confirm whether the gas pipeline is squeezed or twisted, and remove the problem in time. Because the air pressure and flow rate are too low, the electrode will be quickly ablated, the nozzle hole will be deformed and serious gouging marks will be produced.
5. Ensure the correct supply of coolant
Few users pay attention to the coolant, but in fact, the composition of the coolant also affects the life of consumable parts. If the purity of the water in the coolant does not meet the minimum purity requirements, excessive deposits will accumulate on the nozzle, resulting in an unstable arc and causing damage to the nozzle. The working conditions are particularly cold, and the propylene glycol content in the coolant needs to be increased. Otherwise, the severe cold may cause damage to the torch cooling system, rupture of the hose, and lack of cooling cycles will cause damage to the torch. The operator checks the usage of the coolant every day and configures the coolant according to the requirements provided by the supplier is also a way to extend the service life of consumable parts.
6. Reduce human errors and enhance the responsibility of operators
Usually, human error is not starting and breaking the arc on the steel plate, or the plasma arc is not on the steel plate. Reducing human errors will significantly increase the service life of wearing parts, and the operators of CNC plasma cutter need to have a strong sense of responsibility. Accumulate and master the diagnostic knowledge of consumable parts, keep a record of the daily use of consumable parts, replace damaged consumable parts in time, and conduct daily inspections of the equipment's gas, electricity, and piping systems according to the requirements of the equipment supplier, Weekly, monthly, and annual to ensure that the equipment is running well. Good maintenance can increase the life of consumable parts. In addition to the above methods, choosing a manufacturer with leading technology and quality assurance when purchasing equipment is also an important part of reducing operating costs. Advanced processing technology and patented technology such as electrode ramp down patent technology can guarantee the quality of consumable parts themselves.
With the wide application of CNC plasma cutter in various industries, whether they can provide long-life consumables has become one of the important indicators for user companies to judge whether the manufacturer is technologically advanced. Manufacturers are also paying more and more attention to the technological innovation of consumable parts, using advanced thermal modeling technology for design, and adopting special manufacturing processes and boldly applying new materials, making the design closer and closer to perfection. With the introduction of long-life electrodes and the advent of reinforced electrodes and silver electrodes, the life of consumable parts has been significantly improved compared with the traditional ones. In summary, as long as the company manages and operates to select equipment manufacturers with leading technology, select appropriate cutting parameters and methods, use correct consumables, regular inspection, and maintenance of equipment, and strengthen the training and training of operators. Responsibility education will definitely extend the service life of consumable parts to the greatest extent, thereby reducing operating costs.