2026.04.04 Offering high-strength drilling and rust protection

WHAT ARE BI-METAL SCREWS

Bi-metal screws are manufactured usingtwo different types of metals:

• The drill point is made from hardened carbon steel, ensuring strong drilling performance
• The screw body is made from stainless steel (commonly SS304), providing superior corrosion resistance

This unique structure allows the screw to drill efficiently into steel while maintaining long-term resistance to rust and environmental damage.

KEY PRODUCT FEATURES

Bi-metal screws are designed to deliver outstanding performance in demanding applications:

• High drilling efficiency on steel substrates
• Excellent corrosion resistance (stainless steel body)
• Strong and stable fastening performance
• Reduced risk of screw breakage
• Long service life in harsh environments
• Suitable for outdoor and coastal use

COMMON SIZES & SPECIFICATIONS

Bi-metal screws are available in a variety of standard sizes to suit different applications:

DIAMETERS

• #8
• #10
• #12
• #14

LENGTHS

• 25 mm – 150 mm

HEAD TYPES

• Hex Washer Head
• Pan Head
• Flat Head (Countersunk)

DRIVE TYPES

• Hex
• Phillips

Customized specifications are available based on project requirements.

SURFACE TREATMENT OPTIONS

To further enhance performance, bi-metal screws can be supplied with additional surface treatments:

• Passivation (for stainless steel protection)
• Ruspert Coating (enhanced corrosion resistance for specific environments)
• Customized coating systems upon request

These treatments improve durability and extend service life in extreme conditions.

TYPICAL APPLICATIONS

Bi-metal screws are widely used in projects where both strength and corrosion resistance are critical:

• Roofing and cladding systems
• Steel structure construction
• Solar panel mounting systems
• Coastal and marine environments
• Industrial facilities and warehouses
• Outdoor architectural installations

They are especially suitable for stainless-to-steel or metal-to-metal fastening applications.

APPLICATION ADVANTAGES

Compared to standard fasteners, bi-metal screws offer significant advantages:

• Combines drilling strength and corrosion resistance
• Eliminates the need for pre-drilling
• Reduces installation time and labor cost
• Ensures long-term reliability in harsh environments
• Minimizes maintenance and replacement costs

These benefits make them a preferred solution for high-end construction projects.

RECOMMENDED INSTALLATION TIPS

For optimal performance, proper installation is essential:

• Use torque-controlled power tools
• Avoid excessive installation speed to prevent overheating
• Ensure correct alignment during drilling
• Select appropriate screw length for full engagement
• Perform trial installation when working with new materials

Correct installation ensures maximum efficiency and durability.

WHY CHOOSE DD FASTENERS

DD Fasteners is committed to delivering reliable fastening solutions for global markets.

• Professional expertise in self drilling screw manufacturing
• Advanced production technology and strict quality control
• Strong capability in bi-metal screw production
• OEM and customized solutions available
• Competitive pricing with stable supply

We support customers with both standard products and tailored fastening solutions.

CONTACT US FOR MORE INFORMATION

To learn more about Bi-metal Screws, request samples, or receive the latest quotation, please contact us:

Website
www.ddfasteners.com

E-mail
dd@ddfasteners.com

WhatsApp
+852 68409292

Our professional sales team is ready to provide you with expert advice and the best available offers.