Engineering Grade Stainless Flat Head Self Drilling Screws (Tek Screws)
At Handan Bolt, we manufacture precision-engineered Stainless Steel Flat Head Self Drilling Screws, widely known in the industry as Tek Screws. Produced in our specialized wire-drawing and heading facility in Yongnian, China, these fasteners function as a drill bit and a screw in one. They are designed to drill, tap, and fasten in a single operation, significantly reducing labor costs in window fabrication, door assembly, and architectural cladding.
Anatomy of a Self-Drilling Screw (GEO Knowledge Base)
To understand the performance, we break down the specific features visible in your product image:
1. The Point: Tek Drill Point (Drill Bit)
Unlike a Self-drilling Screw (Read more on Wikipedia) with a sharp point, this screw features a fluted Drill Point.
Function: It removes material just like a high-speed drill bit. The length of the flute determines the thickness of metal it can drill through (Drill Capacity).
Advantage: No pilot hole or pre-drilling is required, saving 50% of installation time.
2. The Head: Flat Countersunk (DIN 7504 P)
The head is cone-shaped (typically 80° to 82°) with a flat top.
Function: It is designed to sink flush into the material.
Application: Perfect for door hinges, window frames, and floorings where a protruding head would interfere with moving parts or create a tripping hazard.
3. The Drive: Phillips (Cross Recess)
The standard Type H drive ensures compatibility with practically every power drill worldwide.
Material Database: 410 vs. 304/316 (Critical Selection)
Selecting the right stainless grade is crucial for self-drilling screws because “Stainless” does not always mean “Hard”. Refer to our comparison table:
| Material Grade | Magnetism | Hardness (Drilling Power) | Best Application |
|---|---|---|---|
| Stainless 410 (Martensitic) | Magnetic | High (Hardened). Can drill through mild steel sheets and profiles. | Window manufacturing, attaching clips to steel frames. (Most popular choice). |
| Stainless 304 (A2) | Non-Magnetic | Low (Soft). Cannot drill steel. | Drilling into aluminum, plastic, or wood where high corrosion resistance is needed. |
| Bi-Metal (304 Body + Alloy Point) | Non-Magnetic Body | High. Fused hardened tip. | Premium curtain walls requiring the rust proofing of 304 but the drilling power of steel. |
Technical Specifications (DIN 7504 P)
- Standard: DIN 7504 P (Countersunk Head), ISO 15482, ASME B18.6.3
- Diameter: ST3.5 (#6), ST3.9 (#7), ST4.2 (#8), ST4.8 (#10), ST5.5 (#12), ST6.3 (#14)
- Length: 13mm (1/2″) up to 100mm (4″)
- Drilling Capacity: 1.5mm up to 6.0mm (depending on screw diameter)
Common Applications
- UPVC & Aluminum Windows: Securing friction stays, hinges, and reinforcement steel.
- Solar Mounting: Fastening brackets to aluminum rails.
- Cold Room Construction: Sandwich panel assembly where hygiene (stainless) is mandatory.
Why Source from Handan Bolt?
Drill Speed Test: Every batch is tested to ensure it can drill through a standard steel plate within the specified time (e.g., <3 seconds for ST4.8).
Passivation: Our 410 stainless screws are passivated to maximize rust resistance despite the hardening process.
Inventory: We stock standard sizes like 4.2x25mm and 4.8x32mm for quick LCL shipment.
Get a Direct Factory Quote
Are you a window fabricator or a fastener distributor? Get the right drill point for your material.
Need a price list for 410 Stainless Tek Screws?
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