Automotive supplier Arkal Automotive GmbH can now produce two door side panels parallel at its Crock location in Thuringia, on an MX 1600 – 12000 injection moulding machine from KraussMaffei. This parallel manufacturing process is made possible through the use of a multi-daylight mould.

The unique feature is two LRX linear robots, mechanically coupled on a single axis and operated via a single central control system. They ensure that components are demoulded 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 moulding machine. It had to be capable of processing thirty percent fibre glass-reinforced PP.

It also need to produce two components simultaneously on one injection moulding machine, these components include 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 moulds used by Arkal. The moulds 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 moulds do not tilt. The matching multi-daylight mould was customised for this application. It is equipped with a “flying platen” and mould cooling.

Complex automation solution

A particular challenge was the complex automation of component demoulding and depositing. Arkal chose the solution with an LRX twin robot with the new multiple kinematics control concept from KraussMaffei.

The two LRX 350 linear robots, which are arranged on a joint Z axis, demould 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 demoulding 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

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.