ZHIWEI step drill (different sizes)

1. Design and structure

• Three multi-stage diameter options:

  • 4–12 mm (suitable for fine work)

  • 4–20 mm (general purpose medium-sized holes)

  • 4–32 mm (large industrial needs)

• Conical integrated design: No need to change the drill bit, one drill can complete drilling of multiple sizes.

• Forked tip: self-centering and anti-slip design, can drill stainless steel sheets steadily.

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2. Materials and coatings

• High Speed ​​Steel (HSS) + 5% Cobalt Alloy:

  • 15% harder than ordinary HSS, high temperature resistance up to 650°C, specializing in stainless steel thin plates (1-6mm thickness).

  • Up to 3 times longer wear life than cobalt-free models.
    

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3. Key features

• Special for stainless steel: Optimized for SUS 304/316 thin plates, the drilling edge is smooth and burr-free.

• Step accuracy: Each step hole expansion error is ±0.1mm, ensuring accurate screw/throat assembly.

• Heat dissipation pits: Deep pit design speeds up the removal of stainless steel debris and avoids overheating annealing.

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4. Applicable scenarios

• Stainless steel engineering: kitchen equipment, medical equipment, ship accessories.

• Industrial maintenance: drilling and modification of elevator panels and mechanical casings.

• DIY upgrade: stainless steel anti-theft net, metal furniture production.

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Model comparison table

model	Diameter range	Maximum material thickness	Applicable drilling rig speed
4x12	4–12 mm	6 mm	800–1500 RPM
4x20	4–20 mm	8 mm	600–1200 RPM
4x32	4–32 mm	10 mm	400–800 RPM

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Usage Tips

• When drilling stainless steel, low speed + cooling oil is recommended to prevent coating peeling.

• Regularly sharpening the blade with a diamond grindstone can extend its service life by 50%.