Browning 1128305 Finished Bore Sprocket 18 Teeth

Product Description

The BROWNING 1128305 is a finished bore roller chain sprocket designed for use with standard 40-series roller chain at a 1/2 inch pitch. Machined from steel, this sprocket features 18 teeth, a 1 inch bore diameter, and a 3.14 inch outside diameter. The finished bore is ready for direct shaft installation without additional machining. It is a common component in mechanical drive systems across HVAC, conveyor, pump, and industrial equipment applications, typically installed by millwrights, maintenance technicians, or mechanical contractors working on power transmission assemblies.

This sprocket is suited for light-to-medium duty roller chain drive applications where a compact, fixed-bore steel sprocket is required. The 40-series chain trade size makes it compatible with widely available standard roller chain found in residential and commercial mechanical systems, including belt-and-chain drive arrangements on air handling units, pumps, and auxiliary equipment. The 2.391 inch hub diameter provides adequate material for set screw or keyway retention depending on shaft configuration.

Key Features

• Finished bore at 1 inch diameter — no additional machining required for direct shaft fit
• 18-tooth count with 1/2 inch pitch for use with ANSI 40-series roller chain
• 3.14 inch outside diameter with 2.391 inch hub diameter
• Steel construction for durability in mechanical drive environments
• Compact single-strand sprocket profile suitable for space-constrained drive assemblies

Compatibility

Designed as an OEM-style replacement or standard replacement finished bore sprocket for mechanical drive systems using ANSI 40-series roller chain with 1/2 inch pitch and a 1 inch drive shaft diameter.

Installation Notes

Installation is performed by qualified mechanical technicians or millwrights. Disengage and lock out all power to the drive system before removing or installing sprockets. Verify shaft diameter matches the 1 inch finished bore before installation, and ensure proper chain tension and sprocket alignment per the drive system manufacturer's guidelines to prevent premature chain and sprocket wear.