Cast Iron Drive Pulley 3-Groove 3B Flat For V Belt Pulley OD 80mm 90mm - 180mm

Match the outer diameter (OD) to your required drive ratio — divide the motor pulley OD by the driven pulley OD to get the speed ratio. Then confirm the bore width matches your shaft diameter and the keyway bore matches your key size. All three dimensions (OD × bore width × keyway bore) are listed in each variant name.

These pulleys are machined for the standard B-section V belt profile (also called 3B when used in a 3-groove configuration). They are not compatible with A-section, C-section, or metric SPB/SPC belts. Always verify your belt cross-section before ordering.

Grey cast iron offers compressive strength typically in the range of 100–200 MPa and excellent vibration damping, making it well-suited for belt drive pulleys operating at moderate speeds. It handles the radial and tangential forces from multi-groove V belt drives reliably in workshop and light industrial settings.

Cast iron has moderate corrosion resistance. For indoor workshop or enclosed industrial environments, bare cast iron performs well. If your application involves moisture or outdoor exposure, consider applying a rust-inhibiting coating or paint after installation to extend service life.

Yes — a 3-groove pulley can be used with one, two, or three B-section V belts. Running fewer belts reduces power transmission capacity proportionally. For light-duty applications, a single belt in one groove is acceptable; for full rated torque transfer, use all three grooves with matched belts.

Measure your motor shaft diameter and the existing key dimensions (width × height). The keyway bore listed in the variant (e.g., 6mm, 8mm, 10mm, 12mm, or 14mm) refers to the keyway slot depth/width. Cross-reference with standard key size charts for your shaft diameter to ensure a proper fit before ordering.

These pulleys are commonly used on single-phase and three-phase electric motors, reciprocating air compressors, wood lathes, bandsaws, drill presses, agricultural power take-off systems, and other machinery where a 3B multi-groove belt drive is required for reliable torque transmission.