DM M28 Ø27.5mm Long Thermal Drill Bits with Collar

Industrial Overview: Thermal Friction Drilling Technology

The DM M28 Ø27.5mm Long Thermal Drill Bit with Collar utilizes friction-drilling (flow drilling) technology to generate localized frictional heat up to 600°C–800°C. This softens thin-walled metallic materials, allowing the bit to plunge through and form a seamless, extruding bushing without cutting chips. The resulting bushing expands the effective material thickness by 3x to 4x, enabling ultra-strong M28 threaded connections in sheet metal and tubular structures where direct tapping was previously impossible.

Manufactured from Grade-A micro-grain Tungsten Carbide, the DM M28 thermal drill bit provides maximum resistance to thermal shock, high axial forces, and abrasive wear, ensuring consistent hole geometry across multi-thousand cycle production runs.

Technical Comparison: Standard vs. Flat-Cut Versions

Selecting the correct thermal drill bit geometry is critical for meeting exact engineering specs:

• Standard Round (With Collar): Forms an extended lower bushing while creating a smooth, rounded collar ring on the top surface. Ideal for structural applications where a raised face provides additional load distribution or structural reinforcement.
• Flat-Cut (Planed Collar): Combines bushing formation with an integrated cutting collar that mills off the top raised ring in a single stroke, leaving a perfectly flush surface for flush-mount assemblies.

Key Performance & Technical Advantages

• 300% Increase in Thread Pull-Out Strength: Replaces expensive rivet nuts, weld nuts, and press inserts with single-piece parent material forming.
• 100% Chip-Free Processing: Eliminates metal swarf, cutting fluids, and post-drilling deburring, preventing internal contamination in fluid/gas cooling lines and sealed chambers.
• Precision Collar Formation: Maintains controlled collar height and hole concentricity within ±0.02 mm tolerance.
• Exceptional Tool Life: Superior carbide formulation withstands high RPM and axial load cycles, yielding typical tool life exceeding 3,000 to 5,000 penetrations under recommended operating parameters.
• High-Speed Execution: Typical cycle times range between 2 to 5 seconds per hole, drastically improving throughput over traditional drilling and insert installation.

Primary Industrial Applications

• Automotive & Aerospace Engineering: High-stress structural tubing, frame sub-assemblies, and seat rail mounting brackets.
• HVAC & Liquid Cooling Systems: Heat exchanger manifolds, liquid cooling pipe networks, and boiler pressure vessels.
• Building & Structural Fabrication: Stainless steel architectural fixtures, heavy-duty metal furniture joints, and enclosure frames.
• Industrial Equipment: Heavy mechanical bearing supports, motor mount plates, and high-vibration machinery frames.

Technical Specifications & Compliance

• Nominal Diameter: Ø27.5 mm (Optimized for M28 Thread Cold Forming Taps)
• Material Composition: Micro-Grain Tungsten Carbide (Grade A)
• Recommended Spindle Speed: 1,200 – 2,200 RPM (Depending on base material thickness)
• Applicable Substrates: Mild Steel, Stainless Steel (304/316), Aluminum Alloys, Brass, Copper, Inconel, Titanium, and Tool Steel.
• Standards & Certifications: ISO 9001:2015 quality manufacturing compliant; CE certified equipment integration.