loading
| Availability: | |
|---|---|
Engineered for demanding structural applications, the Hex Head Self-Drilling Screws with Color Painted Head provide exceptional fastening reliability for metal-to-metal connections. Featuring a precision-formed hex flange head, these fasteners deliver a substantial bearing surface that distributes clamping force evenly, protecting delicate exterior panels from distortion during assembly.
The integrated EPDM (Ethylene Propylene Diene Monomer) sealing washer compresses firmly upon installation, creating a permanent, weather-tight barrier that resists moisture ingress and prevents long-term structural degradation. The visually consistent, smooth powder-coated finish can be strictly matched to specific RAL color codes, ensuring seamless integration with diverse exterior architectural designs. Supported by an automated cold heading and threading production line, our manufacturing facility maintains a daily output capacity of over one million pieces, accommodating OEM/ODM custom specifications and ensuring stable supply for large-scale engineering projects.
The bonded EPDM washer acts as a critical barrier, compressing under the flange to form an airtight and watertight seal between the screw head and the attached surface. This tactile, elastic barrier absorbs thermal expansion and contraction, effectively preventing rainwater leaks and localized corrosion even under severe weather conditions.
Manufactured from premium zinc-plated carbon steel or 410 stainless steel, these fasteners undergo rigorous pre-shipment inspections. Through stringent salt spray testing and precise coating thickness measurements, the screws demonstrate exceptional resistance to rust. The surface treatment fully complies with international RoHS and REACH environmental standards.
The engineered self-drilling point eliminates the labor-intensive need for pilot holes. We provide specific TEK point variations to match distinct material thicknesses: TEK 3 points are optimized for 25-16 Gauge thin panels, while TEK 4 and TEK 5 points effortlessly penetrate thicker structural steel. The screw drills, taps, and fastens in one continuous motion.
The hex washer head provides a solid, slip-free engagement with standard nut drivers, emitting a distinct metallic click when locked into the tool. Backed by ISO9001, ISO14001, and IATF16949 quality management systems, every batch passes strict hardness and torque pull-out tests, achieving an impressive tensile strength of up to 180,000 PSI for enduring structural stability.
By integrating the EPDM washer directly beneath the wide flange, the design shields the drilled hole from external elements. This configuration prevents thread loosening caused by wind-induced vibrations, safeguarding the mating metal surfaces from mechanical damage over decades of use.
| Finish | Color Painted |
| Material | High Strength Steel, Stainless Steel,Carbon Steel,Iron, Aluminum Steel |
| Measurement system | Inch, Metric |
| Place of Origin | Ningbo,China |
| Brand Name | Donghuang |
| Standard | DIN, ISO, GB |
| Size | ST3.5-ST6.3, etc,according to customer needs |
Diameter | 8#(4.2mm),10#(4.8mm),12#(5.5mm),14#(6.3mm) |
| Length | Offered in various lengths (e.g., 1 inch, 1.5 inches, 2 inches, up to 3 inches) |
| Tip Type | Self-drilling point |
| Head Type | hex flange head |
| Key Words | Self Drilling Screws, Roofing Screws, Tek Screws |
| Packing | Small box packing/bag or carton packing/as customers' request |
These specialized fasteners are primarily deployed for attaching corrugated metal panels to wooden purlins or heavy steel structures. The customized RAL color heads blend invisibly into the roofing material, while the EPDM washer ensures a secure, waterproof connection that withstands heavy rainfall and intense UV exposure.
Engineered to handle harsh environmental elements, these screws are highly effective for fastening materials in the construction of storage sheds, barns, and agricultural facilities. The anti-corrosion zinc or stainless steel composition guarantees that the structural framework remains intact despite constant exposure to moisture and agricultural chemicals.
Widely utilized in commercial exterior cladding projects to prevent water damage and maintain the building's structural integrity. The precise TEK drilling points allow construction teams to rapidly secure panels without pre-drilling, significantly accelerating project timelines while ensuring a flush, professional finish.
Material Match: Select a screw composition suitable for the base material you are joining, opting for 410 stainless steel in highly corrosive environments or carbon steel for standard metal-to-metal applications.
Drill Point Selection: The self-drilling point length must exceed the combined thickness of the materials being joined before the threads begin to engage. Utilize TEK 3 for 25-16 Gauge sheets, and TEK 4 or 5 for heavier steel plates.
EPDM Washer Verification: Ensure the bonded rubber washer is intact. This component is crucial for creating a watertight seal and preventing friction damage to the painted mating surface.
Tool Setup: Equip a variable-speed power driver or torque wrench with a properly sized hex drive bit. Ensure the bit fits snugly over the painted head to avoid scratching the finish.
Pressure Application: Be prepared to apply firm, consistent downward pressure. This helps the sharp metallic drill point bite into the steel surface and begin the cutting process without walking or slipping.
Position the Screw: Place the pointed tip of the self-drilling screw exactly at the desired fastening location, keeping the driver perfectly perpendicular to the surface.
Engage and Drive: Power the driver at a low speed initially to establish the hole, then bear down with consistent force. The screw will evacuate metal shavings, drill its own hole, and form its own threads simultaneously.
Monitor for Over-Torquing: Watch closely to ensure the screw's threads are not stripping out the base material. Stop driving immediately when the washer seats firmly.
Visual Sealing Check: As the screw reaches its final position, the bonded EPDM washer should visibly compress slightly at the edges to create a secure, waterproof seal without bulging excessively.
No Pre-Drilling Required: The primary mechanical advantage is the total elimination of pilot hole preparation, which dramatically saves labor time and reduces tool wear.
Guaranteed Watertight Seal: The EPDM washer provides a reliable, long-term barrier against moisture for metal roof and wall panel installations.
Vibration-Resistant Fastening: The combination of a wide hex flange head, aggressive self-drilling point, and compressed rubber washer ensures a strong, stable connection that resists wind uplift.
Q: Are Self-Drilling Screw and Tek Screws the Same?
A: Yes, Self-Drilling Screws and Tek Screws are terms often used interchangeably in the construction industry. The "TEK" designation originally refers to a specific brand name that pioneered the drill-point design, which has now become a standard term for fasteners capable of drilling their own holes in metal.
Q: How Do Self-Drilling Screws Differ from Self-Tapping Screws?
A: Self-drilling screws feature a distinct, flute-like drill point at the tip that cuts through metal, eliminating the need for a pilot hole. Conversely, self-tapping screws possess sharp threads designed to cut into material, but they strictly require a pre-drilled pilot hole when working with hard metals or thick steel plates.
Q: How Do I Select the Right Screw Size and Drill Point?
A: Choose the screw size based on the total combined thickness of the materials being joined. The unthreaded drill point must fully penetrate the metal before the first thread engages. For thin materials (25-16 Gauge), a TEK 3 point is ideal. For thicker structural steel, upgrading to a TEK 4 or TEK 5 point is necessary for successful penetration.
Q: Can Self-Drilling Screw Be Reused?
A: While they can be physically removed, it is strongly advised not to reuse a Self-Drilling Screw. During the initial installation, the drill point dulls, and the EPDM washer permanently deforms to match the surface profile. Reusing the screw compromises both its drilling efficiency and its ability to maintain a watertight seal.
Q: Are Self-Drilling Screw Suitable for Outdoor Use?
A: Absolutely. However, for long-term durability in outdoor environments, you must select screws with appropriate corrosion-resistant finishes. Our color-painted screws feature underlying zinc plating or 410 stainless steel construction, paired with UV-resistant EPDM washers, making them perfectly suited for exterior roofing and cladding exposed to rain and sunlight.
Understanding the rigorous demands of large-scale construction projects and international transit, we provide comprehensive industrial packaging solutions. Fasteners are securely packed in moisture-proof plastic bags before being placed into customized color boxes or heavy-duty, thickened outer cartons. For bulk ocean freight, all cartons are securely strapped onto fumigation-free pallets, ensuring the integrity of the threads and painted heads during rough handling and prolonged storage in harsh job-site environments.
Our supply chain infrastructure is optimized for volume procurement. We offer highly competitive volume pricing structures tailored to project scales, alongside flexible payment terms including T/T and L/C. With a robust inventory management system, standard specifications are maintained in stock, enabling a rapid dispatch cycle of just 3 to 5 days to keep your project timelines strictly on schedule.
