In all industries, the drive to reduce energy consumption is making headlines and the aerospace industry in particular is driven to curb energy use through innovative means. Although seals do not always come to mind when thinking of energy reduction, seals can positively impact energy consumption through reduced weight and friction. The task for radial shaft seal suppliers – to effectively prevent leakage while simultaneously keeping friction losses low – is a considerable challenge. As the inventor of the original Simmerring® radial shaft seal, Freudenberg-NOK Sealing Technologies (Freudenberg-NOK) is in an ideal position to meet these new demands.
To accommodate the market trends toward higher surface speeds and lower friction, Freudenberg-NOK developed the Poly Tech Seal (PTS) radial shaft seal in partnership with leading manufacturers looking to increase service life, lower maintenance costs and have reliable performance in demanding, low lubrication environments. The resulting PTS shaft seal design improves sealing by a factor of over 10 times compared to conventional polytetrafluoroethylene (PTFE) sealing products, leading to lower maintenance costs and longer service life.
“During testing, the seal generated 50 percent less frictional torque, making it ideal for compressors, hydrostatic drives and accessory gearboxes,” said Roger Keezer, radial shaft seal competence center manager at Freudenberg-NOK’s Ashland, New Hampshire facility. “We are very pleased with the performance of the PTS seal and excited to be able to offer it as a part of our overall shaft seal portfolio.”
Conventional seals utilize a PTFE element and an O-Ring and gasket clamped between two metallic structural components, requiring a bore sealant to prevent static outer diameter (OD) leakage. Additionally, conventional seals have higher radial loads on the shaft and are often used in series for effective contamination exclusion. By over-molding the seal OD and excluder lip with high-performance elastomer materials, Freudenberg-NOK’s PTS design provides a complete sealing package in one unit and eliminates the need for bore sealant and additional seals.
The elastomeric OD also allows the PTS design to fit into housings constructed from light metals, such as aluminum and magnesium, and requires less maintenance at overhaul. Unique exclusion features prevent dirt and contaminant ingress, making it an optimum choice for a wide range of sealing environments. Lastly, the flexible PTS design allows for the use of various elastomer compounds, offering superior chemical compatibility and temperature capability.
“Even before the original Simmerring seal, sealing innovation has been an integral part of the Freudenberg-NOK culture,” said Sean Morgan, global segment director, Aerospace, Freudenberg-NOK. “Through developments such as the PTS seal, we are continually able to bring value to our customers by helping them meet their efficiency, performance and reliability goals now and into the future.”