Overview
The Martin 2012-1-3/8 taper bushing is a precision-engineered shaft bushing for industrial power transmission. It features 1.375″ finished bore with 5/16″ × 5/32″ keyway and steel construction. This tapered, non-flanged design uses screws to tighten onto the shaft, providing superior clamping force compared to standard keyed bores. Ideal for mounting sprockets, sheaves, and pulleys with secure, flush-mount performance.
Key Features
- Tapered split-bushing design for maximum clamping force on shaft
- Steel construction with precision machining to industry tolerances
- Finished bore with 5/16″ × 5/32″ keyway
- Flush-mount profile—no protruding parts or flange
- Compact, clean design suitable for space-constrained applications
- Works with taper-bored sprockets, sheaves, pulleys, and hubs
Technical Specifications
- Series: 2012 Taper Lock Bushing
- Bore Diameter: 1.3750 in (1 3/8″)
- Keyway Size: 5/16″ × 5/32″
- Length Through Bore: 1.25 in
- Large Diameter (Barrel): 2.75 in
- Overall Length: 1.25 in
- Material: Steel
- Bore Type: Finished with Keyway
- Mounting: Flush-mount (non-flanged)
- Max Hub OD: 3-7/8″, 4-3/8″, 4-3/4″
- Bolt Circle Diameter: 2-5/8″
- Number of Bolt Holes: 2
- Screw Thread Size: 7/16-14″
- Screw Length: 7/8″
- Screw Torque Specification: 280 in-lb
Typical Applications
The Martin 2012-1-3/8 is commonly used in conveyor drives, industrial gearboxes, pump drives, and motor-mounted speed reducers. It is ideal for any application requiring a 1.375″ shaft bore with increased holding power over standard setscrew-only designs. The compact profile suits applications where space is limited and a clean, flush interface is required between the bushing and hub or sprocket.
Compatibility & Replacements
Compatible With
- Taper-bored sprockets (2012 series bore)
- Taper-bored sheaves (pulley applications)
- Taper-bored hubs and couplings
- Standard industrial shafts 1.375″ diameter
- Power transmission equipment with 1 3/8″ bores
Replaces / Drop-In Replacement For
- Warner Electric 2012X1 3/8
- Dodge 2012 1 3/8
- TB Woods TL2012138
- US Tsubaki 2012 1 3/8
Works With
- All 2012-series taper-lock components
- Standard 7/16-14 cap screws and setscrew fastening
- Industrial shaft sizing from 1.1875″ to 1.375″
- OEM and aftermarket sprocket/sheave assemblies
