

High-hardness drill bit
The DSR30C series of externally cooled, short-fluted carbide drill bits are high-efficiency tools developed by JIAYI Tools specifically for high-feed small-hole and thin-walled part machining applications. They feature an "external cooling flute + high-rigidity short flute" design, By achieving breakthroughs in small-hole drilling—including "high-efficiency external cooling, high feed rates without tool vibration, and zero damage to the hole walls"—we have completely resolved the pain points associated with traditional short-flute drills, such as "poor heat dissipation, low efficiency, and susceptibility to tool vibration," It provides reliable small-hole machining solutions for the electronics, mold, and automotive industries, among others.
| Part Number | DSR30C082X |
|---|---|
| Drill Bit Base Material | Ultrafine-Grained Tungsten Carbide Alloy |
| Product Name | Internally Cooled Carbide Drill Bits/Step Drill Bits |
| OEM / ODM | Made to your samples or drawings |
| Specifications | Ø11.80 × 96L × Ø12.0 × 162L |
| Lead time | 2 weeks |
| Packaging (mm) | 15 × 15 × 200mm |
| Blade Diameter DC | Ø11.8mm |
| Blade Length LCF | 96.0mm |
| Shank Diameter DC | Ø12.0mm |
| Overall length OAL | 162.0mm |
| Materials | VHM (ultrafine-grained tungsten carbide alloy) |
| Coating | AlTiN |
| MOQ | 2 pcs |
| Origin | Shenzhen, China |
Design details engineered for accuracy, tool life and process stability.
The cutter body is machined from a single piece of ultra-fine-grain carbide (HRC 68) with no welded joints. It remains stable and free of runout during high-speed, high-feed machining, with a repeatability of ≤0.003 mm.
The drill bit features a double-helix external coolant channel design, allowing the coolant to flow directly to the cutting edge along the channels, improving heat dissipation efficiency by 45% and eliminating the risk of drill bit overheating during high-feed machining.
Utilizing PVD nano-coating technology, the coating has a thickness of 2 μm, a hardness of HV3800, and a coefficient of friction as low as 0.3, resulting in a 1.8-fold increase in tool life compared to traditional coatings.
With a cutting edge length of only 60% that of a traditional drill bit, combined with a constant-diameter, thickened shank design, rigidity is increased by 30%, ensuring no vibration or wobble during high-feed machining.
The drill tip features a 140° centering design with a centering accuracy of ≤0.003 mm, allowing for direct machining without the need to pre-drill a center hole, thereby reducing processing steps and improving efficiency.
Each drill bit passes a G2.5-grade dynamic balancing test, ensuring vibration-free operation at high speeds of 20,000 rpm and guaranteeing machining stability.
The cutting edge is ground using a five-axis CNC grinding machine, with a runout error of ≤0.002 mm, ensuring the roundness and cylindricity of the bore.
Pre- and post-polishing processes reduce friction and ensure excellent chip management
Starting values. Our engineers can tune parameters to your machine and workpiece.
| Workpiece material | Cutting speed vc (m/min) | Feed f (mm/rev) | Coolant |
|---|---|---|---|
| Aluminum Alloy | 80–120 | 0.1–0.25 | Internal + MQL |
| Stainless Steel | 40–70 | 0.06–0.15 | Internal + MQL |
| Steel | 50–80 | 0.08–0.2 | Emulsion |
Typical industries and parts machined with this tool.
Send your hole diameter, depth and workpiece material. We supply standard drills and custom step and special drills made to your samples or drawings.