Published 8/18/2022

K 2022 Preview: Injection Molding Closes the Circle, Digitally

Because the market requires sustainability—and important component of which is the circular economy—and sustainability requires digitization, all three will be major themes at injection molding booths at K 2022.

Tony Deligio

Executive Editor, Plastics Technology

New Machine Lines, New Focus

KraussMaffei (KM), which is working towards making its factories carbon neutral by 2030, noted that away from the K, its new plant in Parsdorf, Germany, features a photovoltaic roof of 7500 kWp (kilowatt peak). The company also announced that it will enter the additive manufacturing (3D printing) space at K 2022 but is saving all the details for the show.

At the show, KM will present its new precisionMolding and powerMolding injection machine series, saying these combine cost-effective production with high performance and rapid availability. The machines will debut in Europe after previously launching in Asia.

KM says the new press series draws from existing machines, with precisionMolding representing a basic version of the all-electric PX series with a reduced number of options, while powerMolding is the counterpart of the company’s proven hydraulic GX series. More standardized designs and less options make delivery time quicker for the machines, according to KM.

At K, a 1300-metric-ton powerMolding press will produce automotive door modules from 100% recycled PP. The recycled material comes from insulin pen caps that KM is molding at the show on a PX 200-1400 machine. The caps are shredded and then prepared on a KM ZE 28 BluePower twin-screw extruder with additives such as bonding agents and liquid dye to create pellets for molding the door modules. Here, the APC plus control software compensates for the batch viscosity fluctuations derived from processing recyclate.

These door modules to be molded at K 2022 by KraussMaffei will begin life at the show as insulin pen caps before being upcycled into the automotive component. (Photo: KraussMaffei)

In addition, a 160-m.t. precisionMolding press will mold a tennis racket from a sugar-cane-based biopolyethylene supplied by FKuR Kunststoff GmbH of Germany (U.S. office in Lexington, Texas). The machine will also utilize KM’s APC plus function to automatically compensate for process fluctuations.

Sister company Netstal will mold a thinwall 150-ml, IML-decorated yogurt cup from certified renewable PP from SABIC on an Elios 4500, which now features a fully electric clamp unit. By switching to all-electric mold closing, Netstal says the machine’s dry cycle is now 0.1 sec faster while average power consumption is reduced by 7kW and the machine is 450 mm shorter. The entire cell—machine, temperature controller, hot runner—will be fully integrated into an MES system. Combining digitization and circular economy, the parts will also feature the HolyGrail digital watermark.

All-Electric, All Efficient

Under the theme of “Act! Sustainably”, Sumitomo (SHI) Demag’s senior director of technology Thorsten Thümen said that all-electric machines are the company’s future and towards that end, the company is working to complete the IntElect 2 platform. First launched with smaller tonnages—50 to 180 tons—the company in 2019 expanded the range from 220 to 500 tons. Basic machines are available in the full range, with higher-speed versions launched in 2018 from 50 to 80 tons. At K 2022, they will offer those IntElect S versions to 450 tons.

In addition, the company will introduce the high-speed PAC-E line of machines, initially targeting packaging and currently available in the medium tonnage range. Described as a fusion of the El-Exis hybrid platform and IntElect all-electric series, it features a brand-new injection unit developed specifically for high-speed packaging. At K, the PAC-E line will debut with an all-electric 350-ton model running a 72-cavity cap mold, with intent to show that the electrified press can achieve the same cycle time as the El-Exis.

Meanwhile, Sumitomo Demag is working on a variant of the El-Exis SP line incorporating servo pumps in the medium and high tonnages to enhance energy efficiency.

Simultaneously, the company continues to pursue in-house development of automation solutions. The SAM (Sumitomo Demag Automation Machine) robotics concept launched at Fakuma 2021 with the SAM-C line. They comprised servo-driven Cartesian robots with payloads of 3, 5, 10 and 20 kg, for presses of 50 to 500 tons and standard applications with cycle times of 10 sec or longer. At the time, Sumitomo (SHI) Demag said the automation offering would be expanded in phases over the next two years and that first expansion will come at K 2022.

The K fair will also showcase the company’s web-based myConnect software, which will present critical data and decision-making information in real time. Sumitomo Demag says all new machines in the future will be equipped with this platform and its range of networked support services, which has been extended to include condition monitoring.

Running Recycled

At a separate K 2022 preview event, held at its headquarters in Schwertberg, Austria, Engel revealed its plans for the show. Engel will debut an injection machine that reportedly can process plastic scrap like flakes directly after grinding. By eliminating pelletizing as a separate process step, Engel says the two-stage press improves energy and cost efficiency in plastics recycling, while also reducing the heat history of the reclaimed material.

At K, Engel will show the two-stage process for the first time as a live exhibit, molding dolly pallets with rollers at the company’s portion of the Circular Economy Forum exhibit at the fair, located in the open air area between halls 11 and 16.

Engel’s two-stage press concept for running recycled materials separates plasticating and injection, while adding degassing and filtration as needed. (Photo: Engel)

In the first stage, the raw material, which could be post-consumer or post-industrial ground flake, is melted in a conventional plasticating screw. The melt is transferred to a second screw for injection into the cavity. Depending on the material and application, a melt filter can be integrated into the process between the stages and a degassing unit in the second stage. Engel says this allows for the creation of high-quality products even from contaminated plastic waste. At the K, a blend of post-industrial polyolefins will be molded on an Engel duo 12060H/80Z/900.

Engel will also process recycled PET at its booth, using a hybrid e-speed 280/50 machine with a specially developed injection unit to mold round 125-ml containers with a wall thickness of just 0.32 mm. Engel notes that in packaging applications where PET is injection molded, it’s typically as a thicker preform which is then expanded into its final thin-wall shape by stretch-blow molding. In this case, the finished IML containers leave the mold ready for filling.

The new high-performance injection unit achieves injection speeds up 1400 mm/sec at a maximum pressure of up to 2600 bar (37,710 psi) when processing small shot weights with an extreme ratio of wall thickness to flow-path length.