Launched into the European market in 2006, a Mazak e-Bot Cell 720 has now been operating in Mazak’s own UK facility for over a year. Machining castings destined for assembly into Mazak machine and lathe centres, the e-Bot Cell 720, a turning centre complete with its own robot loader, has helped to double capacity of large turned components.
Three machines manned by two operators over two 8 hour shifts have now been replaced by two machines, one e-Bot and one manually loaded machine, with one operator over two shifts. The result is two less operators and, with the e-Bot operating to a target 720 hours (24 hours x 30 days) unmanned operation, a doubling in capacity in the area.
In addition to the clear benefits of full machine utilisation, the e-Bot has speeded up load and unload times significantly while helping to reduce the manual handling of heavy loads. Castings weighing up to 140Kgs are handled smoothly and accurately by the robot loader, a FANUC Robotics M900iA which has the capacity to handle up to 350Kgs.
Dave Simkin, Mazak’s Machining Manager, was tasked with implementing the e-Bot Cell into production, he comments, “720 hours runs off the lips quite easily until you fully understand all aspects of production that have to run for the period. The core objective of its implementation is 720 hours unmanned operation and in reality there has to be a period of assessment while this is achieved. Maintaining cutting fluid levels, providing sufficient sister tools in magazines and occasional chuck jaw changes need to be accounted for.”
The e-Bot Cell at Mazak UK is configured with an E500HS2 turning centre with a 1.5mtr bed and a FANUC Robotic M900iA. A conveyor transports stillages of components, stacked three high, into the guarded area of the cell where the robot locates them for loading into the lathe chuck. After completing a layer the robot removes the stillage to access the next layer until the stack is complete.
“We worked closely with the engineering Team at FANUC Robotics UK to make sure all components selected for the cell could be handled by the robot. To remove the need for orientation of components on the stillages, wherever possible, castings were modified to remove any flats and these were then machined as part of the operation.
“Certain components with cast slots couldn’t be modified so a FANUC 2D vision system was incorporated into the robot end of arm tooling. A structured light source over the pick-up point ensures that the vision system isn’t affected by variations in ambient light.
“Total automation of a lathe, compared to a machining centre, is more difficult as chuck jaws need to be sized correctly for differing bar diameters – this makes component selection a core issue to achieve full ‘lights out’ production”, continues Dave Simkin.
More complex components, for example shafts where deeper holes are bored that have potential for swarf clearance issues, are machined on the manned lathe centre. As there has to be an operator in the area anyway there is no plan or need to automate this second machine. Implementing the FANUC robot to the cell was straight-forward explains Simkin as a good relationship existed between the two companies. For the first project meeting FANUC Robotics in the UK had already received feedback from FANUC US on its supply of an e-Bot Cell into the USA. This helped to speed up the process. When the full cell specifications were issued to FANUC, all likely parts to be handled were considered and trials were undertaken. “Successfully implemented, the e-Bot Cell is now producing 300 parts a month and serves as a demonstrator as well as an important part of production – it illustrates confidence in our own products and supports its claimed capabilities,” concludes Dave Simkin.