January 30, 2023
Non-contact machining, such as electrical discharge machining (EDM), laser machining and water jet machining, removes and processes material without the machining tool making direct contact with the workpiece. As with cutting machines, the wave of automation, labor-saving and multitasking is coming to this sector. At JIMTOF2022, many of the latest models to meet these needs were presented, and these trends are expected to continue in the coming year.
EDM is one of the typical non-contact machining processes that utilizes the phenomenon of electrical discharge to cut and machine workpieces. EDM machines include die-sinking EDMs and small-hole EDMs, but at JIMTOF2022, many manufacturers highlighted the development of wire EDMs. Automation and labor-saving is an important trend in the EDM sector as well as in other sectors. In recent years, there has been an increasing demand for automation and labor-saving solutions in EDM.
At JIMTOF 2022, Mitsubishi Electric demonstrated the automation of workpiece changing on its “MP1200” wire EDM machine using a robot. This system uses an industrial robot arm on an autonomous mobile robot (AMR), which can move autonomously and handle multiple machines. High positioning accuracy is required for loading workpieces onto machine tools, but the stopping position accuracy of the AMR is not as high. To overcome this, the system uses a vision sensor on the robot side to read the marks on the machine side to determine the relative position. The robot’s movements are then adjusted based on the positional relationship between the marks and the machine. According to the company, there are still very few examples of EDM machines being automated to this level, but they expect that there will be a need for this type of advanced automation in the future.
Other notable advancements in wire EDMs include extended stroke and improved accuracy. Seibu Electric & Machinery has updated its conventional MB series and introduced it as the new M series. The conventional machining area was a rectangle with a longer X-axis, but the Y-axis stroke has been extended by 50 cm, making the machining area more like a square. In addition, the U-shaped table has been replaced with a hollow-shaped table as standard equipment. According to the technical section manager, “When machining mold plates, only one plate could be set in the past, but now two plates can be set”. Rigidity has also been improved by revising the machine design based on structural analysis, and the “MM35UP” and “MM50UP,” the highest-accuracy models in the M series, have improved machining accuracy from ±2 µm to ±1 µm. There is an increasing demand for ultra-high precision machining at this level, according to the company representative.
Sodick introduced the “AX350L,” an oil-specification wire EDM machine, at JIMTOF2022. This high-end model with an accuracy of ±1 μm is equipped with the “i Groove+ Edition” wire rotation mechanism, which allows the wire to rotate constantly. With this technology, the workpiece is constantly machined on the surface of the wire that is not worn by the rotation of the wire, resulting in no dimensional difference between the top and bottom edges of even thick workpieces and the suppression of machining threads. The stroke for both the X and Y axes is 350 mm square, and the stroke of the Z axis is larger than previous models. Machining is possible up to 120 mm, but the machine can move up to 220 mm, and visibility from the top surface of the workpiece has been improved.
One of the trends in laser processing is complex processing. At JIMTOF 2022, Yamazaki Mazak introduced its new “FG-400 NEO,” a 3D fiber laser cutting machine capable of processing large-diameter long pipes and molded steel. One of the features of this model is that it is equipped with a rotary tool unit. The FG-400 NEO can drill a hole and then tap it, or use the laser to drill a preparatory hole and then tap it. “The spindle for the rotary tool unit is the same as that of the machine tool,” says the person in charge of the machine, and this model takes advantage of Mazak’s strengths as a manufacturer of both cutting machines and laser cutting machines.
In the field of water jet cutting machines, proposals for fully covered, enclosed, and compact models are active. At JIMTOF2022, Sugino Machine exhibited its “ABRASIVE JET CUTTER VARUNA,” which features a box structure that completely encloses the machine. This all-in-one machine is compact in size and includes auxiliary equipment, and has received positive feedback from users.
Flow Japan promoted its “EchoJet”, which made its debut in Asia. The sealed design of the machine reduces noise and splashing. The project coordinator has noted that there is a growing demand for sealed models as users are becoming more concerned about maintaining a good factory environment.
January 24, 2023
January 25, 2023