Always suit the materials to the industrial application
9 May 2022

Using operating parts made of high-quality materials is crucial to ensure reliability and stability of the components and products, cautions Norelem’s Marcus Schneck, so always consider the area of application...
When looking around the factory floor, a gleaming array of metallic instrumentation and machinery will be looking back at you. That being said, innovations in both plastic materials and process capabilities, coupled with changes in industry demands have closed many of the physical and cost performance gaps that once existed between metal and plastic.
The right choice of materials guarantees high-quality, durable products whilst finishes and surface treatments ensure components such as grips and knobs are also visually appealing.
Composite materials, such as glass fibre reinforced PPA (Polyphthalamide) can also be beneficial to use in the manufacturing and engineering sectors due to its lightweight properties, relative stiffness, strength and durability. These materials are growing in popularity too, with the global composites materials market growing at about 5 percent per year, with carbon fibre demand growing at 12 percent per year.
Important selection criteria can be anything from tensile strength, corrosion resistance, operating temperature to chemical resistance.
The use of plastic within the engineering industry has seen that plastic-to-metal conversion can result in savings of 25-50 percent due to the elimination of fastener and assembly needs. Plastic can be used for multiple applications such as hydraulic presses, granulators or plastic extrusion lines to name a few.
Steel, stainless steel or brass offer high impact properties, making these desirable material to use within machinery.
Electrical discharge, friction and high temperatures are three challenges within engineering and manufacturing industries that require specific materials to be used in order for machinery and components to operate efficiently and safely.
Special applications require specific materials - a good example of this is antistatic operating parts. These parts are made of an electrically conductive plastic and thus prevent electrostatic discharges, which can impair sensitive electronic components.
Components made of antistatic thermoplastic which comply with DIN EN 61340-5-1 and can be used in ESD (Electrostatic Discharge) protection zones. These ESD products are also used for devices, components and protection systems in areas with high risk of explosion.
Materials and insulators if chosen correctly can eliminate electrical discharges altogether.
Electrostatic discharges occur quite frequently during production, assembly or transport, antistatic operating elements provide a remedy here. Ensuring components are regularly tested for correct electrical conductivity, whilst carrying the yellow ESD logo for clear identification is vital for the machinery and workers’ safety.
Glass fibre reinforced PPA (Polyphthalamide) - a composite material which, in contrast to conventional plastics, is particularly dimensionally stable - is a common choice of material in a high heat zone. Components made from this material can withstand a temperature of 150°C and short term even temperatures up to 250°C.
Components made of glass bead-reinforced thermoplastic, mainly used for the inside of operational handles, ensure very good wear and gripping comfort - even in wet areas.
When working in a high friction area polyacetal guarantees high hardness and a low coefficient of friction, yet polyketone offers a much longer service life and optimum power transmission. Its exceptionally high abrasion resistance and very good tribological properties significantly reduce susceptibility to tooth fracture.
Bearing surfaces such as lead or copper also reduce the risk of friction amongst components and machinery parts, as does providing sufficiently lubrication.
Of course, metal materials have a trusted reputation for being robust and durable, but plastic certainly can be as good as its metal counterparts and is becoming the go-to material for its flexibility and lightweight properties.
Marcus Schneck is CEO of Norelem