In-cycle FSW on CNC machining centres

Horizontal machining centre manufacturer Heller has introduced the capability to friction stir weld (FSW) non-ferrous components on itsfour- and five-axis CNC machines. It is possible to combine the FSW process with milling, drilling, turning and other metal-cutting operations in the same cycle, saving time by eliminating a separate operation on other equipment – and the expense of buying it.

The integration of FSW into a Heller machining centre requires an inexpensive tool in the spindle, activation of a Heller technology cycle and the adaptive control function in the Siemens Sinumerik 840D sl CNC. The machine operator can easily program the weld path at the control, or else transfer the data from a CADCAM system.

Before welding starts, it is necessary to ascertain two key parameters: axial tool pressure and feed rate along the joint. They depend, among other things, on material composition and the required type and depth of the weld seam. Determining these values can pose a challenge, but Heller’s applications support team are on hand to assist. Pilot projects have shown that customers’ machine operators are quickly able to master the process.

To weld, the tool plunges into the gap between the two parts that require joining with high axial force until it contacts the surfaces.The friction created by rotating the tool heats and eventually plasticises the component material, mixing it to form a bond in the joint gap as the tool, under constant pressure, continues creating a high-quality weld seam along the programmed path. Once the process starts, the Siemens CNC logs the entire workflow.
For further information