Ruland Manufacturing (United States) - Ruland now makes oldham coupling hubs from 303 stainless steel. This addition gives designers an off-the-shelf coupling to choose from when designing systems in corrosive, vacuum or cleanroom environments. Stainless steel oldham couplings are zero-backlash, can accommodate all forms of misalignment and have a balanced design, making them suitable for a wide variety of servo driven applications.
Oldham couplings are comprised of two hubs that mate to a center disk. This three-piece design allows users to easily customize oldham couplings with clamp or set screw hubs with inch, metric, keyed and keyless bores. They have a balanced design for reduced vibration at high speeds of up to 6,000 rpm and operate with low bearing loads, protecting sensitive system components such as bearings from premature failure. Ruland uses a proprietary hub machining process that leaves a smoother surface for interaction between the hub and disk, resulting in longer life and reduced downtime.
The oldham disk is available in acetal for zero-backlash and high torque capacity, PEEK for high temperature and low outgassing, and nylon for dampening and noise reduction. In the event of failure or wear the disk can be replaced, restoring the original performance characteristics of the coupling. Oldham couplings may also act as a mechanical fuse during torque overload situations, with the disk breaking cleanly and stopping power transmission.
The use of 303 stainless steel when combined with a PEEK disk now allows designers to use standard oldham couplings in a wider variety of servo driven applications such as those found in scientific instruments, food processing, packaging and medical. Stainless steel hubs are provided with hardware of like material to maintain consistent corrosion resistance. Ruland adds a proprietary surface treatment to hardware to prevent galling. While the treatment is advantageous for most operating environments, they do outgas and may not be suitable for cleanrooms or vacuum. Users can request untreated hardware as a non-standard or replace it themselves with commercially available hardware.
Ruland stainless steel oldham couplings are available in bore sizes from 3 mm to 20 mm and 1/8 inch to 3/4 inch. Disks can be manufactured with a center hole to allow further shaft penetration or slots for retention hardware to attach the disk to a hub so it can stay in place during disassembly.