Overview
The Martin SK 1 5/8 quick disconnect bushing is a class 30 gray cast iron power transmission component engineered for mounting pulleys, sheaves, sprockets, and other mechanical elements onto drive shafts. This split-flange design delivers robust clamping force while enabling tool-free disconnection for rapid maintenance and component changes. The SK series is standard stock across industrial and agricultural applications requiring reliable shaft coupling with minimal downtime.
Key Features
- Split-flange and tapered bore design for strong shaft clamping and pull-free removal
- Class 30 gray cast iron construction offers wear and corrosion resistance
- Finished bore with 3/8″ × 3/16″ keyway to prevent shaft rotation
- Set screw over keyway to secure key retention on vertical shafts and vibrating loads
- Three mounting holes (5/16-18 threads) with 180 in-lbs recommended torque
- Standard stock configuration for quick availability and cost-effective sourcing
Technical Specifications
- Bore Diameter: 1.6250 inches
- Keyway: 3/8 × 3/16 inch
- Flange Outside Diameter: 3.875 inches
- Flange Thickness: 0.5625 inch
- Barrel Diameter: 2.812 inches
- Barrel Length: 1.375 inches
- Length Through Bore: 1.9375 inches
- Bolt Circle Diameter: 3-5/16 inches
- Number of Bolt Holes: 3
- Screw Thread Size: 5/16-18
- Screw Length: 2 inches
- Recommended Torque: 180 in-lbs
- Material: Class 30 gray cast iron
Typical Applications
Martin SK quick disconnect bushings are deployed across diverse motion control environments including:
- Industrial conveyor and material handling systems
- Agricultural equipment and grain handling machinery
- HVAC fan and blower assemblies
- Manufacturing equipment requiring frequent pulley or sprocket changes
- Construction and mining equipment with high-vibration duty cycles
Compatibility & Replacements
Compatible With
- Standard 1 5/8-inch shaft diameters (finished bore with keyway)
- Martin pulley and sheave products across the SK QD line
- ANSI-standard sprockets and timing belt pulleys
- Industrial drive shafts in machinery and power transmission systems
- Standard 5/16-18 mounting hardware
Replaces / Drop-In Replacement For
- Older Martin SK 1 5/8 bushings (superseded units)
- Generic quick disconnect bushings of equivalent bore and flange dimensions
- Custom-machined shaft couplers on legacy equipment requiring standardization
Works With
- Martin Sprocket & Gear power transmission components
- Standard mechanical power transmission systems (no electronics/software involved)
- Conventional set-screw and keyway shaft coupling methods
- Industrial maintenance and predictive maintenance programs for wear tracking
