Overview
The MasterDrive SD1.3/8 QD Bushing is a quick disconnect (QD) coupling bushing engineered for power transmission and industrial machinery applications. This SD-series bushing accepts 1.3/8″ diameter shafts and mounts directly onto sheaves, sprockets, and rotating equipment. The tapered-cone design provides positive grip without requiring lubricants, making it ideal for maintenance-free, reliable shaft coupling in variable speed and reversing applications.
Key Features
- Quick disconnect (QD) design for rapid assembly and disassembly
- Ductile iron construction resists impact and vibration
- Shallow keyway (5/16″ × 5/32″) prevents shaft stress concentration
- Tapered-cone self-holding mechanism requires no lubrication
- 3 cap screws per bushing for secure flange mounting
- Standard bore: 1.3/8″ (1.375″); flange diameter: 3.1/8″
Technical Specifications
- Bore Diameter: 1.3/8″ (1.375″)
- Flange Diameter (D): 3.1/8″
- Flange Thickness (A): 7/16″
- Bushing Length (B): 2.187″
- Hub Length (E): 7/8″
- Hub Width (L): 1.5/16″
- Keyway Depth: 5/16″ × 5/32″ (shallow keyseat)
- Bolt Hole Center Diameter: 2 11/16″
- Cap Screws: 3 × 1/4″-20 × 1.7/8″
- Material: Ductile Iron
- Bushing Type: SD Series QD
- UPC: 806372019240
Typical Applications
The MasterDrive SD1.3/8 is commonly used in:
- V-belt and synchronous belt drive systems
- Chain sprocket mounting on variable-frequency motors
- Conveyor and material handling equipment
- Agricultural and industrial pump coupling
- Fan and blower assemblies requiring quick coupling
- Equipment requiring seasonal or frequent shaft changes
Compatibility & Replacements
Compatible With
- Sheaves and pulleys with standard QD bore taper
- Sprockets with QD-compatible hubs
- Any 1.3/8″ diameter shaft with standard or shallow keyway
- Power transmission systems rated for standard duty applications
Replaces / Drop-In Replacement For
The MasterDrive SD1.3/8 bushing is compatible with and may serve as a direct replacement for:
- Equivalent SD-series QD bushings from other manufacturers (verify bore taper match)
- Martin Masterdrive SD 1-3/8″ QD bushings
Works With
- Industrial belt and chain drive equipment (standard QD interface)
- AC and DC motor shafts 1.3/8″ diameter
- Gearbox output shafts with QD bushing compatibility
- Reversible and variable-speed machinery
