Overview
The Boston Gear BKF842B-18K-B5-S-M4 is a washdown-duty in-line helical speed reducer built for demanding industrial applications. Part of Boston Gear’s proven 800 series line, this compact reducer delivers consistent torque transmission with simplified maintenance requirements. The unit features an 18:1 reduction ratio, making it suitable for motor speeds around 1750 RPM input.
Key Features
- 18:1 gear reduction ratio for precise speed control
- Compact in-line helical design fits tight mounting spaces
- Double-reduction helical gearing for smooth, quiet operation
- Quill-style motor flange input (B5 mount) for direct coupling
- Solid output shaft configuration (M4 designation)
- Washdown-rated construction tolerates wet and corrosive environments
- Heavy-duty cast-iron construction ensures long-service life
Technical Specifications
Input shaft configuration: Quill-style motor flange (B5 mount)
Output shaft: Solid projecting shaft
Reduction ratio: 18:1
Typical input speed: 1750 RPM (motor speed)
Typical output torque: 35 lbs (approximately 315 in-lbs)
Gearing type: Double-reduction helical
Frame material: Cast iron
Environmental rating: Washdown duty
Lubrication: Oil-bath sealed
Typical Applications
- Food and beverage processing equipment requiring washdown capability
- Chemical processing conveyors and mixers
- Industrial pump and blower drive systems
- Packaging machinery requiring precision speed reduction
- Marine and offshore duty applications
- HVAC and climate-control equipment
Compatibility & Replacements
Compatible With
- Electric motors with NEMA flange mounting (B5 standard base mount)
- 1750 RPM and 1200 RPM AC induction motors
- Motor power ratings from fractional through 2+ HP
- Shaft couplings (flexible or rigid per application)
Replaces / Drop-In Replacement For
- Boston Gear F842B-18K-B5-S-M4 (commercial equivalent)
- SEW Eurodrive helical inline reducers with equivalent 18:1 ratio
- Other 800-series Boston Gear models with same flange and output configuration
Works With
- Standard NEMA motor flanges and standard shaft couplings
- Oil-bath sealed design works with standard industrial gear oils ISO 46–68
- Mounting: Base-mount (floor or machine frame installation)
- Both horizontal and vertical mounting orientations
