Ruland Manufacturing MOST41-11-A Coupling Hub

Ruland MOST41-11-A is an aluminum Oldham coupling hub with an 11 mm bore and a 41.3 mm outside diameter, designed for precise shaft-to-shaft connections in a three-piece modular coupling. This set-screw style hub forms part of a configurable system: two anodized aluminum hubs press-fit onto a center disk, enabling combinations with different inserts and disks to tailor torque, stiffness, and misalignment handling. Key specifications include bore 11 mm, outer diameter 41.3 mm (1.625 in), hub width 18.0 mm, and total length 50.8 mm. The design accommodates angular misalignment up to 0.5°, parallel misalignment up to 0.010 in (0.25 mm), and axial motion of 0.006 in (0.15 mm), with a balanced configuration to minimize vibration. It is rated for speeds up to 4,500 RPM and supports a range of shaft tolerances (+0.000 / -0.013 mm); disks are available in multiple materials to match performance needs. The assembly is engineered for low bearing loads and zero-backlash in typical operation, and the hardware is metric. Ruland manufactures MOST41-11-A in Marlborough, Massachusetts from North American-sourced bar stock, and the product line is RoHS3 and REACH compliant with ISO 9001:2015 quality controls. When paired with the appropriate center disk and inserts, this hub delivers reliable torque transfer in motion-control and automation applications that require precise alignment tolerance and compact form factor.