WFL offers turnkey system for flexible, fully integrated machining line

With the set-up station for workpieces and tools, tools can be set up and new workpieces can be loaded parallel to machining time and without restricting automation. (Courtesy: WFL Millturn Technologies)

Automated and flexible systems are now playing a crucial role in the production of workpieces. WFL Millturn Technologies has taken a decisive step toward its aim of highly intelligent, automated production with the completion of a customer project. Manufacturing is carried out with a central turnkey system, to which four complete machining centers are attached.

WFL Millturn Technologies has always been involved in the field of automation. From articulated robots to gantry loaders, every system combined with a mill-turn brings a high-tech element into production halls. The acquisition of FRAI Elektromaschinenbau GmbH in 2018 represents another step toward innovation in complete machining, paving the way for a digital future.

Autonomous production methods have long been used by automotive manufacturers, the aerospace industry and, above all, mold construction companies to produce equipment for machine tools. Other sectors with less of a focus on automation are nonetheless showing increased interest in this area, due to the possibility of introducing autonomous night and weekend shifts. WFL Millturn Technologies works with different automation variants such as gantry loaders and articulated robots for automated workpiece loading and unloading, depending on each customer’s requirements. Peripheral transport and storage systems for workpieces, tools, and clamping devices can be combined as desired.

This brings some key advantages for the user, such as continuous productivity with minimal operating effort. Automated machines are also ideally suited to repetitive tasks. However, robots are not only used in large-scale series production; there are also many advantages to automation for small batch sizes, when used in combination with easy-to-program software.

Customer-specific options, such as unloading samples, inscribing, cleaning, measuring blank parts, or even additional processing tasks performed by the robot-like deburring, provide optimal conditions for automation.

An automation solution implemented by WFL has been specially developed for flexible batch production and is designed for the automation of four machine tools for handling different shafts. The 6-axis robot with a 500-kilogram payload is mounted on a 7th axis. An automatic gripper exchange system has also been attached so that a wide variety of grippers can be connected and disconnected automatically as required when the system is operating in automatic mode. An integrated drip tray collects coolant and chips.

Thanks to the fully automatic quick-change gripper system and gripper warehouse, five different grippers are used in specific applications: servo grippers for workpieces and shafts, grippers for prismatic tools (such as long boring bars), grippers for tailstock tips, and grippers for three different inner and outer jaws.

The jaws can be changed over fully automatically in the automated solution by means of a special chuck. The tailstock tips can also be changed over automatically using a special gripper. Another special gripper is able to automatically change the long prismatic tools (boring bars up to 2,500 mm long and 250 kilograms in weight).

By using two separate set-up stations for workpieces and tools, tools can be set up and new workpieces can be loaded parallel to machining time and without restricting automation.

The system has three control levels: the KUKA KRC robot, the Siemens PLC sequence control and safety technology, and the host computer for cell logic and logistics. The host computer — which manages the CNC programs centrally and makes machines available — as well as tool management and material flow planning optimizes machine utilization, minimizes downtimes, and enables autonomous or low-personnel manufacturing.

Automatic changeover of jaws, tailstock tips, and prismatic tools in conjunction with a servomotor gripper (diameter and length plausibility), which covers an extremely wide product range, allows for set-up-free operation of the machines and automation solution.

The warehouse serves as a “lung” and the host computer as the “brain,” meaning that the production plant also manufactures both small series and batch sizes of one without restriction. The host computer configures an optimized production program based on the available tools and workpieces so that the system can be operated autonomously overnight or at weekends without manual intervention.