TCT Annular Cutter Guide: Tungsten Carbide Tipped Core Bits for Heavy Steel Drilling

TCT (Tungsten Carbide Tipped) cutters utilize micro-grain cemented carbide tooth inserts induction-brazed onto a high-alloy spring steel body. While standard High-Speed Steel (M2/M35) begins losing hardness around 500°C–600°C, tungsten carbide maintains exceptional hot hardness past 900°C. In heavy structural I-beams, stainless steels (304/316), abrasive cast iron, and high-tensile railway tracks, TCT cuts at more than twice the peripheral surface speed (SFM) of HSS with 3x to 5x greater overall tool lifespan, dramatically reducing machine downtime and labor per hole.

Carbide tips possess outstanding compressive strength and abrasive resistance but low tensile/impact ductility. Premature breakage is usually triggered by three common culprits: 1) Weak magnetic holding base or unstable workpieces allowing the drill press to rock during cutting; 2) Inconsistent manual feed pressure causing tooth snatching; or 3) Ejection failure of the center slug at cycle completion. To prevent damage, ensure a minimum 12mm flat steel surface for magnetic chuck adherence, maintain continuous internal pressurized coolant through the center pilot pin, and ease off feed pressure slightly upon penetration breakthrough.

Jiangsu WRD Tools Co., Ltd. manufactures four core arbor connections: 1) Standard 19.05 mm (3/4") Weldon Shank with two grub-screw flats—compatible with majority magnetic drills globally; 2) 31.75 mm (1-1/4") Weldon Shank for heavy-bore cutters above 65 mm; 3) Universal One-Touch Shank featuring 3 ball detents and 1 drive flat—allowing fast tool-free chucking in Nitto Kohki machines while maintaining full compatibility with regular Weldon arbors; and 4) 4-spoke Quick-In shanks customized for Fein magnetic drills.

Yes. Although re-sharpening TCT annular cutters requires precise CNC tool and cutter grinders equipped with resinoid diamond wheels and designated indexing cams to preserve the alternating triple-cut rake and relief angles, cutters can routinely be re-sharpened 3 to 5 times. As long as the carbide insert is not fractured across the braze line or worn down to less than 0.8 mm thickness, re-sharpening delivers substantial cost savings over complete tool replacement.

For standard stocked sizes, our minimum order quantity starts at just 10 pieces or 5-piece boxed sets. For custom OEM branding, we accommodate private laser engraving (logos, custom part numbering, and sizing), custom depth specifications (35 mm, 50 mm, 75 mm, 100 mm), advanced protective coatings (TiN, TiAlN), and branded high-impact plastic or aluminum cases with custom molded foam. Sample orders are dispatched within 5–7 days, with commercial container orders completed in 30–35 days.

Internal lubrication via the spring-loaded center pilot pin is essential. The pilot pin serves a dual mechanical function: it accurately aligns the cutter over the center punch mark before drilling, and during cutting, retracts inward to open the internal arbor coolant valve. Pressurized cutting oil flows directly across the internal flutes to the carbide cutting edges, cooling the braze joint and flushing chips away. Upon complete breakthrough, the pilot spring expands forcefully, violently ejecting the solid waste slug to prepare the drill immediately for the next cycle.