ENGEL at the DKT IRC
High prices for raw materials and energy are making life difficult for processors right now. At DKT IRC from 27 to 30 June 2022 in Nuremberg, Germany, ENGEL is showcasing innovative solutions in the form of three exhibits to show how seals, O-rings, and even the smallest precision parts made of elastomer materials can be produced in a competitive way despite these conditions.
Producing in a competitive and cost effective way with reliable precision is more important than ever in our times of high raw material and energy prices. At DKT IRC 2022 in Nuremberg, ENGEL is presenting both the process-assured flexseal series specially designed for seals, and a tie-bar-less and all-electric ENGEL e-motion TL for very small precision parts. In addition, an e-victory is producing diaphragms on site to show the positive impact that tie-bar-less technology has on overall efficiency and unit cost.
During the four days of the event, O-rings are being produced from solid silicone (HTV) at the ENGEL stand, using a 102-cavity mould on a servo-hydraulic ENGEL flexseal 500/300 T. The flexseal series injection moulding machines are intelligently adapted to meet the special requirements of O-ring and flat seal manufacturers. Suited to all popular rubber compounds and silicones, the flexseal machines offer great precision thanks to the horizontal machine design with a screw injection unit – an important feature, as seal production often involves small shot volumes.
The ENGEL roto feeder feeds in the solid silicone continuously, avoiding inclusions and keeping the pressure constant. The rotating hopper with counter-rotating screw ensures a very high level of process stability. The rotofeeder was specially developed by ENGEL for processing solid silicone and BMC.
Fully automatic processing on the flexseal is achieved through brushing devices. The series is also characterised by its particularly compact dimensions.
One of the main drivers of the flexseal model series' great energy efficiency is the ENGEL servohydraulic ecodrive, which the flexseal machines have as a standard feature. With ecodrive, the motors are only active when the machine is moving. However, during the longer heating phases required for elastomers, the drives are stationary and do not use any energy.
A tie-bar-less and all-electric ENGEL e-motion 50/30 TL injection moulding machine is producing ultra-small precision components for the field of ophthalmology with an individual part weight of 0.0013 grams on a valve gated cold runner mould with 32 cavities. The filigree parts measure 1.7 mm in length and 0.9 mm in diameter.
A precision LSR plasticising pump, and a camera system for quality control – both implemented by ACH Solution, Fischlham/Austria – and an ENGEL viper 12 linear robot are supporting the automated precision production of micro-parts.
However, the tiny parts are only made possible by a new LSR micro-injection unit, which ENGEL developed in collaboration with ACH Solution. Thanks to this innovative injection unit, ENGEL injection moulding machines can produce precision parts from liquid silicone rubber with a shot weight of well below 0.1 grammes from now on.
The LSR micro-injection unit is not just extremely precise: during development, the focus was also on great flexibility and cost-effectiveness. Thanks to a quick coupling system, the unit can be exchanged for a conventional screw injection unit in less than 30 minutes to maximise the production uptime of the injection moulding machine.
The new micro-injection unit will above all benefit processors who supply customers in medical technologies or the consumer electronics industry. Among other applications, very small electronic precision components and high-quality optical components are required for smartphones.
Further applications can be found in the automotive industry, driven by electric mobility and autonomous driving. ENGEL will also be using the new micro-injection unit to implement multi-component processes, for example, to inject sealing elements with very small shot volumes directly onto a base body.
Low unit costs are essential to be competitive, and productivity per unit of area is a key performance indicator of this. As mould mounting platens on a tie-bar-less e-motion TL injection moulding machine can be used fully, right up to the edge of the platen, large and bulky, multiple-cavity moulds can be mounted on relatively small injection moulding machines. This reduces the capital expenditure and operating costs while at the same time shrinking the machine footprint to further boost productivity per unit of area.
Other LSR applications also benefit from tie-bar-less technology – which is still a unique selling point of ENGEL today – as the third machine exhibit by ENGEL at DKT IRC clearly shows. Diaphragms made of LSR with a total shot weight of 18.4 grammes are being produced on a tie-bar-less ENGEL e-victory 265/80 equipped with a 16-cavity mould. Project partner Elmet from Oftering/Austria provided the mould and LSR plasticising technology.
Tie-bar-less technology not only allows for a small footprint, but also the lower energy consumption this entails. What's more, this technology also simplifies automation as the robot can access the cavities directly from the side, without needing to work around interfering contours, and operate safely within the mould area. At DKT IRC, an ENGEL viper 6 linear robot is being used in the production of the diaphragms.
High precision is built into the design of tie-bar-less machines. The patented force divider enables the moving mould mounting platen to follow the mould exactly while clamping force is building up and ensures that the clamping force is evenly distributed across the platen face. This means that both the outer and inner cavities are kept closed with exactly the same force, which reduces mould wear and raises product quality. After all, burr-, waste- and rework-free and fully automated processing of LSR is the most important prerequisite to producing competitive high-tech products made of liquid silicone rubber – and not only in economically challenging general conditions.
An energy- and resource-saving approach not only reduces the unit costs, it also makes a major contribution towards protecting the climate. Beyond the machines' drive technology, it is digitalisation that above all helps to leverage the machines' full potential. For example, iQ weight control smart assistance system analyses the pressure profile during the injection process and compares the measured values with a reference cycle. In each individual cycle, the injection profile, switchover point and the holding pressure profile are adjusted to the current conditions, and this keeps the injected volume constant during the entire production run. The result is high product quality across the board. Rejects are proactively prevented. At DKT IRC, ENGEL is using iQ weight control in the production of precision micro-parts on the e-motion TL and of the diaphragms on the e-victory injection moulding machine. Visitors to the fair can watch the smart assistance systems live on the CC300 control panels of the injection moulding machines.