Injection of glass fibers reinforced PA is a challenging procedure for some, as it requires specific plastic injection molding skills, knowledge, and the ability to address possible issues. These include flow and mold filling problems, inadequate surface quality and incorrect fiber orientation, all of which may occur and harm the product. These challenges require skilled knowledge for correct mold planning and appropriate injection conditions in order to address and prevent the problems in advance.
The complexity increases when working with even more challenging polymers, for example engineering and technical materials such as PEEK, ULTEM and others. The cost of a mistake also increases, as these raw materials are especially costly.
Glass fibers reinforced nylon is the new PP
Working with such engineering polymers is routine at Rion. In fact it is difficult to challenge us with a request to manufacture a product from an unusual raw material. In reality, most injections performed at our plant are not with commonly used PP or PE, but rather with nylon reinforced with a high percentage of glass fibers, even up to 60%. Over the years we have worked with almost every material and welcome any such new challenge. Thanks to our excellent and professional Molds Department we have successfully overcome these challenges time and time again!
A high manufacturing standard for every job
Rion applies a particularly high manufacturing standards in working with engineering materials, suitable for high melting-temperature materials that may even erode the equipment. This begins with employee training and the development and integration of proper work procedures, and is also considered when acquiring new equipment. Our injection machines are acquired from the leading world manufacturers, with the screws and barrel suitable for working at high temperatures of up to 450°C which are characteristic of engineering materials. All our molds are manufactured at a high standard – SPI 102. The mold cooling system is planned for optimal cooling, without connectors and with a manifold on every machine. Our peripheral equipment is also suitable for these work conditions, including temperature controllers for working at high temperatures that can even reach 400°C.
Which engineering materials pose a challenge in the mold injection process?
- PES / PEEK / ULTEM – a polymer requiring high-temperature processing. Both the manufacturing and peripheral equipment must be suitable for these temperatures.
- PVC – the mold and the metal parts that come in contact with the PVC must be made of stainless steel to prevent rust, and at Rion we have a fleet of machines suitable for this work. As this material is very sensitive to the injection process, we have specific work procedures for working with this material. The machines are also equipped with a fume extractor to suck the air and prevent the release of evaporable and toxic substances from the material into the work area.
- PVDF – similar to PVC. The screws and barrel must also possess the needed chemical resistance and high-temperature processing ability for this material.
- Reinforced nylon – combines short or long glass fibers as well as carbon fibers in a wide range of weighted percentages that can even reach 60%. The fibers exert significant erosion forces on the mold and on the molten material conveyance system, and these are taken into consideration in planning the process, regarding both the injection machine and the mold.
- TPU / TPE – these polymers are elastic, and as such their flexibility requires special consideration compared to rigid polymers, mainly during part extraction stage. While working with these materials, it is important to mitigate stress through heat in designated ovens.
- PC / PS – Material transparency is an important property in planning the mold and the flow, in addition to avoiding trapped stresses and discernable connection points.
Don’t shy away from investing in new projects
Rion’s high level technical abilities and our highly experienced Molds Department, enable us to work successfully with any technical and engineering material used in industry. We also accompany our customers and provide professional advice in recommending alternative raw materials if needed for product improvement. We do not shy away from investment when a certain project requires process adaptations or unique equipment, as has been the case in certain past projects. We are committed to providing excellent service and to maintaining and enhancing our technical abilities.Image 1: Nylon PA6 reinforced with glass fibers.