Overview
The Martin 40NB19H is a needle bearing Type B idler roller chain sprocket engineered for power transmission and conveying applications requiring smooth, low-friction chain operation. This steel sprocket features hardened teeth and precision bore for reliable performance in drive systems where chain direction changes or tension adjustment is required.
Key Features
- Needle bearing Type B construction for smooth, low-friction idler operation
- Hardened steel teeth for extended sprocket and chain life
- ANSI standard compliant design for compatibility with #40 single-strand roller chain
- 19-tooth design with 0.5″ pitch optimized for compact drive ratios
- 1.0″ solid bore; easily customizable with keyways or setscrews
- 2.5″ hub diameter provides stability and alignment in multi-sprocket systems
Technical Specifications
- Chain Size: #40 (1/2″ pitch)
- Number of Teeth: 19
- Bore Diameter: 1.0 inch
- Outside Diameter: 3.3 inches
- Hub Diameter: 2.5 inches
- Pitch Diameter: 3.038 inches
- Length Through Bore: 1.0 inch
- Bearing Type: Needle Bearing Type B
- Material: High carbon steel with hardened teeth
- Tooth Width: 0.284 inches
Typical Applications
The Martin 40NB19H idler sprocket is ideal for:
- Industrial conveyor systems requiring smooth idler operation
- Chain drive direction changes or tension adjustment points
- Light to medium-duty power transmission systems
- Machinery with space constraints favoring compact idler designs
- OEM replacement on existing #40 chain drive systems
Compatibility & Replacements
Compatible With
- #40 ANSI single-strand roller chain (0.5″ pitch)
- Standard 1.0″ bore shafts with keyways or setscrew mounting
- Type B hub systems used in conveyor and light industrial drive equipment
- Equipment designed for needle bearing idler operation
Replaces / Drop-In Replacement For
- Verify compatibility with your OEM documentation before ordering, as idler sprocket bore and hub configurations vary by equipment manufacturer.
Works With
- #40 ANSI roller chain and chain couplings
- Standard industrial shaft sizes 1.0″ and smaller with bore modification
- ANSI-compliant sprocket drive systems operating up to moderate speed and load
