Norton 66623399001 Flap Disc 60 Grit Type 27 4.5 Inch

Product Description

The NORTON 66623399001 is a Type 27 ceramic alumina flap disc designed for aggressive material removal on metal, weld seams, and fabricated surfaces. Rated to 13,300 RPM and available in 60 grit (medium grade), this disc delivers fast stock removal with a longer service life than standard aluminum oxide alternatives. The polyester backing resists heat and flex fatigue during extended grinding passes. At 4.5 inches in diameter with a 5/8-11 arbor attachment, it mounts directly to standard angle grinders used in fabrication, structural, and pipe welding applications. The trimmable flap design allows the operator to expose fresh abrasive as the disc wears, extending usable life on the job.

This flap disc is suited for use in metal fabrication shops, structural steel work, pipeline welding, and general weld blending. The Type 27 flat-profile design is appropriate for flat and edge grinding where a low grinding angle is required. Grinding professionals, pipefitters, ironworkers, and welding fabricators typically reach for this disc when working on carbon steel, stainless, and hard-facing alloys that demand a more durable abrasive grain than conventional aluminum oxide.

Key Features

• Ceramic alumina abrasive grain for longer disc life and faster cut rates versus aluminum oxide
• 60 grit medium grade for aggressive stock removal and weld blending
• Type 27 flat profile suited for flat surface and edge grinding applications
• Polyester backing resists heat buildup and flex fatigue during prolonged use
• Trimmable flap construction exposes fresh grain as disc wears, maximizing disc life
• 5/8-11 arbor fits standard angle grinders without adapters

Compatibility

Designed for use with standard 4.5 inch angle grinders equipped with a 5/8-11 threaded spindle. Confirm your grinder's no-load RPM does not exceed the disc's 13,300 RPM maximum rating before mounting.

Installation Notes

Installation should be performed by qualified personnel following grinder and abrasive manufacturer guidelines. Always power down and unplug the angle grinder before mounting or removing a flap disc. Inspect the disc for cracks, tears, or damage before each use and do not mount a disc that shows any signs of defect. Eye protection, gloves, and a face shield are standard PPE when operating angle grinders with abrasive discs.