60458 - PFERD POLIFAN PSF Z-EXTRA 4-1/2" x 7/8" Zirconia Flap Disc, 40 Grit, Type 27

High-Performance Zirconia Abrasive for Industrial Applications

The PFERD POLIFAN® PSF Z-EXTRA 4-1/2" x 7/8" Flap Disc (SKU: 60458) represents a significant advancement in the Universal Line of abrasives, designed specifically to bridge the gap between standard performance and premium longevity. Engineered with German precision, this Type 27 (flat) flap disc utilizes a high-quality Zirconia Alumina (Z) grain, known for its self-sharpening properties and durability under thermal stress. The "EXTRA" designation in the PSF Z-EXTRA series indicates a construction featuring approximately 40% more abrasive cloth material compared to the standard PSF line. This increased density translates directly to extended service life and reduced downtime associated with disc changeovers, making it a highly cost-effective solution for high-volume fabrication environments.

The disc features PFERD's STEELOX technology, a formulation that ensures compatibility with both carbon steel and stainless steel (INOX). This dual-application capability simplifies inventory management for workshops handling mixed materials. The abrasive grains are bonded to a robust fiberglass backing plate which provides necessary rigidity for aggressive stock removal while remaining flexible enough to prevent glazing. Unlike plastic backings that can melt and smear onto the workpiece under high heat, the fiberglass backing ensures a clean grind without contaminating the surface. The 40 grit specification makes this disc ideal for coarse grinding tasks, such as leveling heavy welds, chamfering edges, and rapid stock removal.

Technically, the flap arrangement is designed to offer a cushioned grinding effect, reducing vibration and operator fatigue. While the disc is optimized for high-powered angle grinders to fully exploit the Zirconia grain's fracture characteristics, it maintains excellent performance on low-power drive systems as well. The Type 27 flat profile is preferred for surface grinding applications where the operator grinds at a flatter angle (0° to 15°), providing maximum contact area for smoothing and blending.