Product Features
Dual-Edge/Multi-Edge Insert Design: Typically employs a composite structure consisting of a central insert and outer inserts; the central insert handles centering and initial cutting, while the outer inserts expand the hole diameter. The inserts are predominantly square or hexagonal in shape, with each insert providing multiple cutting edges (typically 4 to 8). Upon wear, the inserts need only be indexed or replaced, allowing the drill body itself to be reused.
Self-Centering and High-Efficiency Drilling: Featuring specialized asymmetrical cutting edge geometries or chip-breaking groove designs, the drill bit possesses a self-centering capability, thereby eliminating the need for a pre-drilled pilot hole. Drilling precision can reach tolerance grades of IT9 to IT11, with a surface roughness (Ra) ranging from 3.2 to 6.3 μm. Machining efficiency is significantly higher than that of traditional twist drills; cutting speeds can be increased by a factor of 2 to 3, while feed rates are also substantially higher.
Superior Chip Evacuation and Cooling: The tool features internal dual-helical cooling channels that deliver high-pressure coolant directly to the cutting zone, forcibly expelling chips and effectively preventing chip clogging. Selected models are equipped with specialized chip-breaking geometries, ensuring controllable and well-segmented chips-making them particularly suitable for deep-hole drilling applications (with length-to-diameter ratios reaching 5:1 to 8:1).
Diverse Materials and Coatings: The inserts primarily utilize a carbide substrate, enhanced with PVD coatings (such as TiAlN, AlCrN, etc.) to provide exceptional heat and wear resistance. This enables stable machining across a wide range of materials, including steel, stainless steel, cast iron, and high-temperature alloys. The drill body is typically constructed from alloy steel and undergoes surface nitriding treatment to enhance its wear resistance and impact strength.
Cost Reduction: Compared to solid carbide drills, indexable drills offer a lower cost per hole; since the drill body remains reusable over an extended period after the inserts are indexed or replaced, overall tool management becomes significantly more economical.
Maintenance and Care
After each use, inspect the cutting edges of the inserts for chipping; verify that the width of the wear land does not exceed 0.2–0.3 mm. The center insert typically wears faster than the outer insert and requires periodic indexing or replacement. It is imperative to replace inserts in pairs (the center and outer inserts must not be mixed if they are in different states of wear).
After using the drill, promptly clean any residual chips and cutting fluid from the chip flutes and coolant channels of the tool body. A soft-bristled brush or a high-pressure air gun may be used for this purpose; strictly avoid using hard objects that could scratch the sealing surfaces of the tool body or the locating surfaces of the insert seats.
Inspect the locating surfaces of the insert seat for any burrs or indentations; if necessary, lightly dress them using an oilstone. It is recommended to replace the screws used to secure the inserts every 5 to 10 uses to prevent fatigue fracture. During assembly and disassembly, use a torque wrench to tighten the screws to the manufacturer's recommended torque specifications (typically 3–8 N·m).
Use a clean coolant supply with sufficient pressure (an internal coolant pressure of ≥10 bar is recommended) to prevent thermal cracking of the inserts or the sintering of chips caused by inadequate cooling. Before shutting down operations, allow the drill bit to idle within the coolant stream for a few seconds to flush out any residual internal debris.
After cleaning, apply a rust-inhibiting oil to the tool. Store the tool in a dedicated tool sleeve or storage case to prevent the tool body from sustaining deformation due to impact or the inserts from being accidentally damaged.
Hot Tags: indexable drill, China indexable drill manufacturers, suppliers, factory
