R+W SERVOMAX – Elastomer Coupling with Fully Split Clamping Hubs Model EKH
EKH elastomer couplings feature fully split clamping hubs which allow for quick lateral installation and removal between shafts without the need to move or realign the connected components. In most sizes the hubs are precision machined from solid round-bar stock rather than cast, and provide backlash free, low inertia torque transmission through a calibrated, wear-resistant elastomer insert (spider).
Precision elastomer couplings are used in a wide variety of drive applications including lift systems, conveyors, pumps, linear actuators, and high-performance power transmission in general. The EKH design offers many advantages for machines where performance cannot be compromised. Two clamping screws per hub generate stronger shaft clamping pressure than traditional single screw designs. This can prevent slippage for smaller shafts at higher torque levels and increase the torque capacity per coupling size in general when used in keyless clamping configurations, while keyways are also available on request. The maximum runout tolerance of 0.03mm between the bores and jaw pockets ensures smooth running even at higher speeds. The precision machined hub geometry includes curved drive jaws to increase the contact surface area with the insert and create a more durable coupling system overall.
Vibration can also be mitigated with the right selection of insert material. The most commonly used elastomer inserts are thermoplastic polyurethane in varying Shore hardness levels and temperature ranges, which can filter out unwanted vibration and help absorb shock loads. For use in potentially explosive atmospheres a special electrically conductive version, which can be certified under ATEX, continues a path to ground for any possible electrical discharge between the coupling hubs, which could otherwise have the potential to arc across the jaws. A special Hytrel® insert can be used in harsh environments, and a stainless-steel mesh version can be used under extreme operating conditions. Each plastic insert is calibrated through a secondary match-molding process before installation to ensure an easy fit while still creating a preload and maximizing the surface area contact between the jaws and insert material. This ensures a high torque capacity and a backlash free coupling system that can be used in reversing applications.
EKH couplings come in a variety of sizes and torque ratings from 10Nm to 25,000Nm. With metric or imperial shaft bore diameters which can be mixed and matched, ranging from 6mm up to 5-1/2”, they can be used in a wide range of applications where easy installation is desired. Many custom features can also be requested for the elastomer coupling series including custom hub materials such as steel or stainless steel, special surface treatments, special mounting hardware, and precision balancing. Custom bore designs can be integrated into the hubs upon request, including splines, dual keyways, and D profiles.
Another benefit of using the EK series is that all models within the same size are interchangeable. The jaw design of the couplings does not change based on the clamping mechanism, which creates a modular product line and allows customers to create combination couplings to best suit their needs. R+W carries stock of EKH base components and can expedite orders if fast delivery is necessary.
For more information or to size and select EKH couplings, contact R+W or visit the product page!