WELCOME TO Shengde
The Leading
Manufacturer of
Bi-metal Screws
- Expertise in Manufacturing Bi-metal & Stainless Steel Screws
- Total Quality Management ISO 9001:2015
- 24-Hour Technical Support & Lifetime Services
About Company
Leading Bi Metal Screw Supplier & OEM Factory in China
Shengde Fastener is a professional bi metal screw manufacturer located in Guangfu Industrial Park, Chongqing, China. As a dedicated OEM factory, we specialize in high-performance SS304/316 +SS420/SCM435 bi metal self drilling screws, self tapping screws, and concrete screw anchors.
Our 6,000 m² manufacturing facility operates advanced automated production lines supported by a comprehensive ERP management system, ensuring precision, traceability, and consistent quality in every batch. With a monthly capacity of 5M to 6.5M pieces, we are well equipped to serve global distributors, contractors, and construction projects.
Certified under ISO 9001:2015, our factory integrates a fully equipped in-house laboratory featuring Vickers hardness testers, tensile testing machines, and drilling performance testing equipment. Every product undergoes strict inspection to meet international standards.
Engineered for demanding environments, our bi metal screws combine the corrosion resistance of stainless steel with the strength of hardened alloy steel. With salt spray test performance exceeding 1,500 hours, our fastening solutions deliver long-term durability in harsh outdoor and industrial applications.
We welcome global partners to visit our Chongqing manufacturing facility for on-site inspection and long-term cooperation.
HOT PRODUCTS
Dual-Material Design:
- Hardened AISI 420 drill point and the first tapping threads + 304/316 stainless main part
→ Strong drilling + Long-lasting corrosion resistance
Super Corrosion-resistant and Durable:
Advanced anti-rust coating
1500h salt spray resistance
Withstands 25 acid rain cycles
50-year service life in normal conditions
Bi-metal
Screws SOLUTION
features
Quick Self-Locking
Drilling, tapping, and fastening in one step. Strong and reliable locking.
Superior Thread Performance
Sharp, precise threads. Efficient tapping into thick and hard materials with chip removal grooves.
High Penetration Power
Innovative blade head, drills stainless steel easily. Fast drilling and accurate positioning.
application
🟧 Steel Structure Projects
🟧 Subways, Airports, and Railway Stations
🟧 Roofing & Facade Fixings
🟧 Coastal and Marine Projects
🟧 Pre-fabricated Building Assemblies
Screws Compositions: (%)
| Material | C (max) | Mn (max) | P (max) | S (max) | Si (max) | Cr | Ni | Mo |
|---|---|---|---|---|---|---|---|---|
| SUS420 | 0.16–0.25 | 1.00 | 0.04 | 0.03 | 1.00 | 12.00–14.00 | 0.60 max | – |
| SCM435 | 0.33–0.38 | 0.60–0.90 | 0.03 | 0.03 | 0.15–0.35 | 0.90–1.20 | 0.25 max | 0.15–0.30 |
| SUS304 | 0.08 | 2.00 | 0.045 | 0.03 | 1.00 | 18.00–20.00 | 8.00–11.00 | – |
| SUS316 | 0.08 | 2.00 | 0.045 | 0.03 | 1.00 | 16.00–18.00 | 10.00–14.00 | 2.00–3.00 |
Our team of experts is ready to help you.
Have specific requirements? Send us a quick message — our team will get back to you with a tailored quote and the best solution for your project.
Industry Solutions
We are innovation and excellence in bimetal screws to deliver unparalleled solutions for your construction project needs.
Our Certifications
With years of expertise in design, production, and quality control, our screws are trusted in sectors such as the Airports, high-speed rail stations,sports venues,power stations,subway stations, railway,steel structures,chemical plants, curtain walls and other fields and more.
TESTING eQUIPMENT
Precision and reliable testing equipment, safeguarding the quality of every screw.
Salt Spray Test Machine
Verifies corrosion resistance and surface durability, ensuring each product meets strict anti-rust standards and customer expectations.
Tensile Testing Machine
Our tensile testing process confirms the mechanical strength of metal components, ensuring durability and compliance with both international norms and custom-engineered requirements.
Hardness Testing Machine
Surface and core hardness are thoroughly tested to confirm the mechanical integrity of fasteners, ensuring performance under demanding applications.
Polishing Machine
Enhances the surface smoothness of screws after grinding, ensuring more accurate and consistent Vickers hardness testing results.
Vickers Digital Hardness Tester
It allows for testing both the surface and core hardness of the screw, providing a clear and intuitive understanding of its condition through the machine.
Image measuring instrument
We employ state-of-the-art 3D measurement technology to capture and verify critical data points, ensuring our metal components meet the most demanding tolerances and performance standards.
Torque Testing Machine
Measures the torque strength of metal fasteners to ensure compliance with international standards or tailored specifications.
Need Help?
FAQs
Our Mission: Commit from beginning to completion, fully loyal to our partners and agreements.
Is Shengde a manufacturer or a trading company?
Shengde is a manufacture company. We produce self drilling screws, self tapping screws, machine screws and concrete screws.
Why Shengde bi-metal screws are the best choice for your next construction project?
Bimetal Screws combine a corrosion-resistant A2/A4 stainless steel body with a hardened SUS420 drill point for fast, reliable drilling in tough environments. Cost-effective and efficient, they help reduce installation time and labor costs.
What materials we could choose for the fasteners?
Stainless Steel: 304,316,410
Bi-metal: SS304/SS316+ SS420
What surface treatment do you have? and the salty spray time?
Most of our screws come with zinc plating or Ruspert coating.
Zinc plating usually lasts 24–100 hours in salt spray tests.
Ruspert can handle up to 500–2000 hours.
If you need better protection (like acid rain resistance), we also offer coatings tested for 5–25 Kesternich cycles. Just let us know what you need — we’re happy to customize.
What screw head types can you provide?
We’ve got plenty! From common types to special custom ones — just let us know what you need.
Here are the screw heads we usually make:
PAN, OVAL, H.W.H, H.W.F, C.S.K, LAEGE WAFER, PANCAKE, BUGLE, PAN FEAMING, HINGE, WAFER, TRUSS
Not sure which one works best for your project? Drop us a message — we’re happy to help!
Are bi-metal screws suitable for harsh coastal environments?
Yes, absolutely. Our bi-metal screws are engineered specifically for high-corrosion environments. The drill point is made of hardened alloy steel for drilling, while the body is high-grade 304/316 stainless steel. This combination provides excellent corrosion resistance, passing 1500+ hours of neutral salt spray testing.
What is the drilling capacity of your bi-metal self-drilling screws?
Our standard bi-metal screws are capable of drilling through steel structures with a thickness of up to 6-14mm Q355B. They are designed to maintain structural integrity and prevent snapping during the drilling process in heavy-duty applications.
Why choose bi-metal screws over solid stainless steel screws?
While solid stainless steel offers great corrosion resistance, it often lacks the hardness required to drill through thick steel. Bi-metal screws combine the best of both worlds: the superior hardness of a carbon steel drill tip (allowing for fast, easy installation) and the rust-proof properties of a stainless steel body.
Do you offer customization (OEM/ODM) for bi-metal fasteners?
Yes, as a professional manufacturer, we offer full OEM/ODM services. We can customize head types, lengths, coatings, and packaging according to your specific project requirements or engineering drawings.
Why Choose Us
Global Standards
Factory Direct
By controlling the entire production cycle internally, we eliminate middleman markups. Experience the perfect balance of strict quality control and competitive wholesale pricing.
Full-Spectrum
OEM Solutions
Engineered to your exact specifications. We manufacture lengths from 16mm to 400mm, with fully customizable head geometries and advanced surface treatments.
Includes complimentary inspection reports and certification for volume partners.
Rapid 30-Day Delivery
We optimize our production scheduling to guarantee a standard 30-60 day lead time according to the quantity. Keep your projects on track and your inventory stocked without the long wait.
Contact our experts immediately today
We are innovation and excellence in bimetal & stainless steel screws to deliver unparalleled solutions for your construction needs.