(Munich, June 27, 2016) Left and right in a single shot: The automotive supplier Arkal Automotive GmbH produces two door side panels parallel on an MX 1600 – 12000 injection molding machine from KraussMaffei at its Crock location in Thuringia. This is made possible through the use of a multi-daylight mold. The unique feature: Two LRX linear robots, mechanically coupled on a single axis and operated via a single central control system, ensure that components are demolded and deposited quickly and reliably. Together they enable short cycle times and high precision.
Two components in a single shot
High precision and short cycle times were one of the basic requirements for designing a suitable injection molding machine. It had to be capable of processing thirty percent fiber glass-reinforced PP. Another requirement: Two components were to be produced simultaneously on one injection molding machine, namely side panels for the left and right-side front or back door for a Tier 1 supplier. "We were able to shorten cycle times considerably by implementing an MX 1600 – 12000 in combination with an LRX twin robot," explains Thomas Marufke, Managing Director at KraussMaffei Automation. Arkal currently manufactures approximately 3,600 door side panels per week in three shifts, alternating between front and back panels.
The MX series from KraussMaffei excels here thanks to its high melt quality and particularly reliable shot weight consistency. The hydromechanical dual-platen clamping unit developed by KraussMaffei ensures fast production. Particularly the platen parallelism of the MX series proves the worth of the large multi-daylight molds used by Arkal: The molds do not get damaged and are thus protected against wear. High-quality components can be produced over a long period of time. The MX series also ensures that the large multi-daylight molds do not tilt. The matching multi-daylight mold was customized for this application. It is equipped with a "flying platen" and mold cooling.
Complex automation solution
A particular challenge was the complex automation of component demolding and depositing. Arkal chose the solution with an LRX twin robot with the new multiple kinematics control concept from KraussMaffei. "The combined linear robots with multiple kinematics offer us considerable advantages when it comes to durability, flexibility and convenience," explains Thomas Reichl, Manager of Production & Maintenance at Arkal. The two LRX 350 linear robots, which are arranged on a joint z axis, demold the components in a parallel process, and move them to and deposit them in the component storage area. This so-called TwinZ design is ideally suited for transferring components (handshake) during fast component demolding and stacking. This configuration also provides significant space and time savings for automation processes with overlapping motion ranges.
More operating convenience thanks to a single central control system
"The premiere for this robot type in this design has been extremely successful. This is the first time that we combined two mechanically coupled x/y axes of the LRX series on a z robot axis with a new control concept," says Marufke. Thanks to this design, both linear robots as well as the MX 1600 can be programmed and controlled via the central MC6 control system. "This makes operation of the complex system significantly more convenient," explains Reichl, Manager of Production & Maintenance at Arkal. The robots are programmed via the shared program editor. Program commands and parameters can be assigned to individual robots with minimal effort. A joint coordinate system for all axes makes it easier to control specific robots in individual operating modes.
More about Arkal
Structure-reinforcing components made primarily from fiber glass-reinforced plastics are the trademark of the Crock location in Thuringia, owned by Israel-based Arkal Plastic Products. "Our expertise comes into play whenever metal components need to be replaced by parts made from lightweight, reinforcing plastics," says Reichl. Typical applications include functional parts, center sections of wheels and battery compartments. Customers include renowned OEMs as well as Tier 1 suppliers. The production location in Thuringia houses 11 injection molding machines, 8 of which are from KraussMaffei. The company has already planned additional investments.