Comparison of Plasma and Ultrasonic Robotic Cutting
When it comes to robotic cutting automation there are several types of cutting methods to choose from. Two of those methods are plasma cutting and ultrasonic cutting. Both are ideal for robotic automation. Understanding the process behind each along with their advantages is key to determining which will be the most beneficial to a manufacturing process.
What is Robotic Plasma Cutting?Robotic plasma cutting involves using the same power supply and EOAT as plasma welding. Plasma welding robots are able to perform plasma cutting by accelerating the plasma jet to create a cut instead of a weld. A FANUC Arcmate 120ic can plasma cut workpieces to prepare them for welding and then switch to welding them by slowing the plasma jet for maximum efficiency.
During the cutting process, an electrical arc is formed by compressed gas, which becomes ionized and turns into the plasma. As the articulated robot applies the torch to the workpiece, the material melts and is blown away creating a cut.
Plasma cutting robots can cut through both thin and thick metals but are especially beneficial for thick metal cutting. Any metal that is electrically conducive can be cut with a six axis robot. The ABB 4600-20 can cut through steel, aluminum, and copper.
What is Robotic Ultrasonic Cutting?Ultrasonic cutting is the newer of the two cutting methods with only recently being automated by robots. Although it is relatively new, it is starting to replace many traditional robotic cutting applications. Unlike plasma cutting that relies on an electric arc and ionized gas, ultrasonic cutting involves the use of knife blades to create cuts. Industrial robots are integrated with ultrasonic cutters for their end-effectors. Ultrasonic robots will apply the blades to the workpieces where a powerful force of electricity is created through microscopic vibrations sent through the blade, allowing for smooth cuts with very little pressure applied. The Motoman MH50-20 and the FANUC M710ic/20L are both ideal for robotic ultrasonic cutting.
Ultrasonic cutting robots can cut through a variety of materials but are best suited for those with less resistance or those that are soft or viscous. The vibrations of ultrasonic cutters prevent soft materials from sticking to the blade when the welding robot is done cutting. This results in clean, even cuts of materials such as foam, textiles, food, rubber, and plastics.
Advantages of Robotic Plasma CuttingThe advantages of robotic plasma cutting over ultrasonic cutting include:
- • The capability to cut through a variety of metals, up to 80 mm in thickness. Robotic ultrasonic cutting is not conducive for cutting through metals.
- • Cycle times are faster with robot plasma cutting, especially when cutting thick metals. On average, plasma cutting robots can complete applications in one-fourth the amount of time than other methods.
Advantages of Robotic Ultrasonic CuttingRobotic ultrasonic cutting offers the following advantages over plasma cutting:
- • Ultrasonic cutting robots like the FANUC M20ia can cut through a greater variety of materials. While plasma cutting robots have the advantage when it comes to metal cutting, ultrasonic robots can handle just about every other material type.
- • Robotic ultrasonic cutting tends to be lower maintenance and has fewer consumable costs. The tooling blades only require re-sharpening and can be reused several times.