LASCAM: Large Scale Laser Cutting of Plastics Brings Significant Savings to Production and Increases Efficiency

Specifically, it was a robotic laser workstation following the plastic injection moulding process using back injection moulding technology, which is part of a fully automated line for the production of door panels.

Picture No.1 – The interior of a fully automated line

Laser cutting is widely applicable to many polymer, sandwich and composite materials, especially those made by using back injection moulding technology. Examples are materials based on ABS, PMMA, PP or PE with appropriate fillers and composite components. This technology was therefore also chosen for a customer who had previously processed materials manually using mechanical cutting and local punching, which required a large number of operators, typically 24 employees in 3 shifts.

However, by implementing robotic and automated laser technology affiliated to the injection moulding machine, the customer eliminated all manual processing and replaced it with stable robotic production. 

Picture No.2 - Workplace layout

What is back injection moulding?

A technology in which material is injected into a mould with a pre-prepared foil. The result is a moulding coated with this foil (see image 3).

Picture No.3 – Part before (left) and after processing (right)

How does it all work?

The laser workstation consists of two sections, each operated by one 6-axis industrial robot. In the first phase, the part (door frame) is picked up by the robot from the input conveyor. Then it moves the part under a static laser head where a 200 W CO2 laser cuts off the excessed foil, which extends around the perimeter of the part, with required accuracy of ±0.2 mm.

The part is then handed over to a second robot, which moves it in front of a 3D scanning laser head with a unique 792 x 718 mm field of view, where Circular cutting of the foil is processed to access mounting holes and holes for audio or airbag wiring. In total, 27 holes are cut in just 15 seconds by using a 400 W CO₂ laser. The final part is transferred to the output conveyor of the line for further subsequent application.

Benefits of this solution

After the installation of laser technology, the customer appreciates the stabilization of quality, especially the repeatability of the production process and the significant improvement in production efficiency. Thanks to the fully automated robotic workstation, the error rate and total time of all operations have been significantly reduced. The customer has also gained a major competitive advantage by saving considerable costs in manpower and consumables that could be used in other parts of the production. In addition, thanks to the multi-functional concept, the entire workstation can be additionally programmed to produce parts for other car models and thus expand the possibilities of its use in the future.

Picture No.4 – Final usage of the part

Main features and benefits:

• Acceleration of the production cycle

• Non-contact process

• Automatic correction of the robot's path in relation to the laser beam

• Fully automated solution connected to downstream applications

• Without the accumulation of excessive heat and w undesirable impact in the processed part

• Process repeatability with an accuracy of ±0.2 mm for the entire part up to a size of 1200 x 1200 mm

• Competent replacement for traditional cutting, punching and milling processes

• Significant reduction in number of personnel required to operate the workstation

• Multi-functional concept allowing easy re-programming for other parts

• Reduction in workstation area compared to manual machining