When it comes to product cleanliness and quality in medical technology, the requirements are high. KraussMaffei will be demonstrating how a PX 50-180 SilcoSet can satisfy these requirements with high precision and productivity in the growth market of silicone at the Swiss Plastics Expo exhibition taking place from the 24 – 26 of January 2017 in Switzerland.
Flexibility is the key
The PX 50-180 SilcoSet is exemplary of the high degree of modularity and precision of KraussMaffei’s new, all-electric PX series. “The modular concept of the PX is especially beneficial in the micro-injection of silicone, where extremely small shot weights, but also large platens are required,” explains Bruno Schleiss, Managing Director KraussMaffei Schweiz AG.
The ejector of the PX 50-180 SilcoSet is electric and encapsulated, so it corresponds with the strict clean room requirements of medical technology. The compact design provides lots of space for demoulding and peripheral equipment and good accessibility.
Another highlight is a servo-hydraulically powered injection unit for the nozzle contact force, which guarantees reliable and leak-free injection of the low-viscosity liquid silicone (LSR) material through the open cold runner. The version with two pressure cylinders provides for even power transmission and high stability. Other equipment features of the SilcoSet machine at Swiss Plastics include a water-cooled cylinder, an electrically heated mould and a vacuum pump for mould ventilation.
High precision and greater stability
The production of LSR diaphragms weighing just 0.03 g and measuring just 0.2 mm thick in a 32-cavity mould requires particularly high precision. Unlike thermoplastics, LSR does not shrink in the cavity, but rather expands, meaning precision is primarily the result of accuracy during injection.
Here, the PX series scores particularly well by being an all-electric injection moulding machine. Another highlight is the plasticizing process, which has been specially configured for applications with silicone.
It features a separate non-return valve with precise closing characteristics. The linear guidance of the moving platens also provides for precise, low-friction clamping movements, even with high mould weights.
KraussMaffei’s new APC plus function takes on a particularly important task, for it compensates for the batch fluctuations commonly encountered when processing LSR.
The new PX – the all-electric benchmark
The new KraussMaffei PX series sets new standards for all-electric machines. The series is the first all-electric machine which the customer may tailor to his specific manufacturing needs using a modular principle in the hydraulic area.
These include, for example, enlarged platens, faster injection speeds or even the option for operation using food-grade NSF H1 lubricant.
For clean room compatible applications in medical technology, the PX features encapsulated drive units and ejector and a closed lubricant circuit. In continuous operation, the PX features an ergonomically favourable working height of 130 cm, which remains the same for all clamping forces, ensuring perfect accessibility of the mould and nozzle for setup or during production.