Software simplifies design of plastic gears

Paul Boughton

Sabic Innovative Plastics has collaborated with Swiss software firm Kisssoft AG to take the guesswork out of plastic gear design. To accelerate the trend toward replacing metals with high-performance, durable and versatile thermoplastic compounds, Kisssoft is now applying gear sizing calculations for 17 grades of Sabic Innovative Plastics' LNP specialty compounds, including high-temperature, internally lubricated and fibre-reinforced grades. Now, engineers and designers can replace trial-and-error with validated data on parameters such as strength, temperature resistance and tooth flank wear in order to streamline the gear design process. This can help a wide range of industries - from healthcare and automotive to food services - to leverage the advantages of plastic gears to cut cost, expand design freedom, reduce weight and deliver higher performance.
Dr Stefan Beermann, the chief executive of Kisssoft, states: "A major roadblock to designing plastic gears has been the lack of reliable data. Sizing calculations for metal gears cannot be applied to plastics because plastics' performance properties can vary with temperature. Our work with Sabic Innovative Plastics has enabled Kisssoft to incorporate the properties of a large group of the company's high-end compounds into our calculation software, radically simplifying the gear design process. Whether the gears are for cable car systems, construction equipment, Formula 1 race car transmissions or spacecraft, customers can now select and evaluate Sabic Innovative Plastics' specialty compounds quickly and accurately."
Metal-to-plastic conversion represents a major trend and a significant improvement in gear technology. Plastic gears deliver a number of improvements over traditional metal alternatives, beginning with significantly enhanced design freedom. Moulding instead of machining enables new configurations to be used, while avoiding the costs of secondary operations. The lighter weight of plastics also reduces inertia for greater gear efficiency. Additionally, moving plastic parts are significantly quieter than metal, which helps to reduce noise from machinery.
Rob Janssen, a technical marketing product specialist with Sabic Innovative Plastics, says: "Sabic Innovative Plastics has always been proactive in adding value to our materials portfolio to help customers achieve the best results in the shortest time. By collaborating with industry experts such as Kisssoft to provide validated engineering data, we make it easy for customers to design new applications with our materials and take them to market quickly. Kisssoft's software with data on LNP specialty compounds is a powerful new tool for wide-scale conversion of gears to high-performance thermoplastics."
The first group of Sabic Innovative Plastics' LNP materials to be validated includes reinforced grades using short and long glass fibres and carbon fibres, various lubricant technologies and eight different base polymers. Data for these grades, provided by Sabic Innovative Plastics, include temperature-dependent values for modulus, static bending strength and characteristic wear values during dry running. The two companies are working to expand this portfolio.
Sabic Innovative Plastics' LNP specialty compounds are also claimed to offer additional high-performance advantages. For example, LNP Lubricomp and LNP Lubriloy compounds with internal lubrication can be used in dry-running gears for applications that do not permit the external application of oil and grease. The healthcare and food services sectors are key markets for these materials due to regulatory requirements for cleanliness and safety. Other benefits of internally lubricated compounds include cost savings from reduced maintenance and enhanced environmental protection.
Fibre-reinforced grades of Sabic Innovative Plastics' compounds can further improve the endurance performance with respect to wear and fatigue resistance and enable the transmission of higher torques.
For more information, visit

Recent Issues