Plasma vs Oxyfuel Robotic Cutting
Cutting applications have become popular for robotic automation. The speed, precision, and control of industrial robots optimizes the process, resulting in smooth and even cuts. While it is easy to decide to automate a cutting application with a robot, determining which type of cutting process to implement may not be. There are several types of cutting applications that can be automated with industrial robots. Robotic plasma cutting and robotic oxyfuel cutting are two of the most commonly used by today’s manufacturers. Understanding the key differences between these cutting applications will be helpful in determining which is appropriate for your operation.
Cutting ProcessRobotic plasma cutting can be performed by a plasma welding robot as the torches used for both are interchangeable. A FANUC Arcmate 120ic can plasma cut a workpiece and then go directly to plasma welding without changing tooling. Instead of using plasma to heat and melt metals together, the plasma is used to separate metals by accelerating the plasma to a faster speed. A six axis robot will apply the plasma torch to the desired cut location, separating the metal through the high speed of the plasma. In addition to the welding robot, a power source, plasma torch, and compressed air will be needed in order to automate an application.
For robotic oxyfuel cutting an articulated robot is integrated with a torch, fuel tank, and oxygen tank. Most welding robots can be used to automate an oxyfuel cutting process. Plasma torches can also be setup for oxyfuel cutting. The ABB 2400 and the Motoman MA1400 are two factory robots that are ideal for oxyfuel applications. During this process the robot will apply the torch to the workpiece, pre-heating it with the fuel flame, creating slag. The robot will then direct a jet of oxygen to push through the slag, separating the metal.
MetalsRobotic plasma cutting provides greater workpiece flexibility since it can cut through a variety of metals with varying thickness. Any electrically conductive metal can be cut with a FANUC M-710ic/20L using plasma. These include steel, aluminum, and copper. Plasma cutting robots can handle both thin and thick metals of up to two inches in thickness.
Robotic oxyfuel cutting is more limited on the types of metals it can cut through. Only thick metals containing iron are candidates for oxyfuel robots. A ABB 4600-20 can cut through metals up to twenty-four inches in thickness using the oxyfuel method.
Cycle TimesCycle times are much faster with plasma cutting robots. Since there is no pre-heating required, setup is kept to a minimum saving on time. Cycle times are also sped up since the metals being cut are thinner than those cut with oxyfuel robots. Plasma cutting robots are extremely fast with the ability to cut up to five hundred inches per minute.
Cycle times will be slower with robotic oxyfuel cutting and it is one of the main drawbacks to the process. Having to pre-heat the metals before cutting can begin increases the amount of time it takes to complete a workpiece. In addition, cutting through thicker metals will be more time consuming in general.