Full definition
A V-belt or timing pulley designed to mount on a shaft via a QD (Quick Disconnect) tapered bushing system, predominantly used in North America. The QD bushing has a steeper taper than the European Taper Lock, allowing rapid installation and removal with three capscrews. Standard QD bushing series by bore range: JA (3/8"-1"), SH (1/2"-1-3/4"), SDS (5/8"-2"), SD (7/8"-2-15/16"), SK (7/8"-3-3/4"), SF (1-3/16"-4-7/16"), E (1-7/16"-4-15/16"), F (1-15/16"-5-7/16"), J (2-7/16"-6"). The bushing is installed first on the shaft with a key, then the pulley slides over the taper and screws draw it tight. For removal, screws are moved to jacking holes. Interchangeable among all major US manufacturers: Browning, Martin, Dodge, TB Woods. Hub material: cast iron (standard) or ductile iron (heavy duty). Per ANSI/RMA standards.