Why Choose HSS Annular Cutters Over Twist Drills? The Engineering Guide to Industrial Holemaking

M2 grade high-speed steel (W6Mo5Cr4V2) is the global benchmark for carbon structural steels, aluminum, and cast irons below 750 N/mm² tensile strength. It possesses excellent toughness that resists shock and chattering. M35 contains an additional 5% Cobalt, raising hot-hardness and elevating red-hardness temperature thresholds above 620°C. For industrial environments processing high-tensile structural beams, Hardox wear plates, or austenitic 304/316 stainless steels, M35 cobalt annular cutters prevent thermal wear and provide more than double the tool life per edge.

In standard drilling, large continuous metal chips tend to bird-nest and jam inside deep flutes, causing premature cutter breakage. Jiangsu WRD Tools Co., Ltd. employs a proprietary alternating inside-outside-center tooth cutting geometry. Each progressive tooth removes a discrete segment of the overall kerf width, breaking the single broad chip into three distinct slender ribbons. These ribbons clear rapidly along optimized parabolic helical flutes while pressurized coolant forced through the hollow pilot ejector pin flushes chips out cleanly.

Yes. Resharpenability represents one of the major economic benefits of HSS annular cutters over TCT core drills. An HSS annular cutter can be sharpened 3 to 6 times using specialized CNC or manual core cutter sharpeners before the back-taper clearance is compromised. Resharpening restores the face rake and end cutting relief while preserving the factory-specified inner/outer step heights, enabling end-users to reduce expendable tooling costs by 40% to 55% over the total life of the cutter.

We supply three internationally recognized mounting standards: 1) Standard 3/4-inch (19.05mm) Weldon Shanks featuring two machined locking flats at 90 degrees; 2) Universal / One-Touch Shanks incorporating dual Weldon flats alongside three radial ball-bearing detents suitable for Nitto-type keyless quick-change chucks; and 3) Fein Quick-In shanks featuring four perimeter engagement grooves for rapid lock-and-release mounting without hex keys.

For standard metric and imperial individual diameters, our minimum order quantity starts from 50 pieces per size, while complete multi-piece boxed sets start from 10 sets. We support private-label brand programs, including high-resolution fiber-laser brand marking, custom diameter/depth etchings, bespoke laser-cut EVA foam inserts, blow-molded or aluminum transport cases, and client-specified barcode packaging.

The pilot ejector pin serves three critical functional duties: First, its hardened conical tip locates the punch mark to guarantee hole location accuracy. Second, upon drill motor activation, the spring-loaded arbor displaces the internal pin, opening internal oil-way channels to deliver continuous pressurized cutting lubricant directly to the cutting teeth. Third, upon breakthrough of the metal plate, the compressed internal ejector spring propels the solid center slug out of the cutter, preventing cycle delays.