Hertel WPMT-32.52LF HP520B Trigon Carbide Boring Insert (8 Pcs)

This listing is for 8 new Hertel WPMT-32.52LF carbide trigon boring inserts in grade HP520B (Hertel catalog item 3557084001, barcode K2161), manufactured in the USA. Decoding the ISO-style designation: W = trigon (80° included angle, triangular) insert shape; P = 11° relief (clearance) angle; M = medium tolerance class; T = insert with a hole and top clamp (countersunk); 32 = 3/8 in (9.525 mm) inscribed circle size; 52 = 5/32 in (3.969 mm) insert thickness; LF = low-force geometry chipbreaker. HP520B is a PVD TiN-family coated carbide grade targeted at medium-to-finish boring of steel and cast iron; the warm golden/bronze coating color visible in all photos confirms a PVD TiAlN or TiN-class coating rather than CVD alumina. The LF (low-force) chipbreaker geometry features a positive rake face with a pronounced chip groove, reducing cutting forces and heat generation — making these inserts well-suited for finish boring, tight-tolerance internal turning, and light interrupted cuts on steel and ductile iron in WPMT-style boring bars and cartridges. Compatible toolholders accept WPMT trigon inserts with a top-clamp/countersunk mounting hole; the 3/8 in IC size is used in small- to medium-bore boring bars.

Product Specifications