A: It depends.If we have bulk goods in stock, we can ship goods within 3 days after the QC process. If we don’t have stock, normally it takes 7-15 days for OEM samples and 20-30 days for bulk goods. If it refers to opening the new mold, it takes an extra 7-15 days to make the mold.
Self-drilling Screws For Roof Waterproofing
Self-Drilling Color-Coated Steel Roofing Screws: Overview
Materials:
- Carbon steel (high-strength, heat-treated for drilling capability) with zinc-aluminum coating (corrosion resistance) or stainless steel (AISI 304/316 for harsh environments).
- Color-coated finish: PVDF (polyvinylidene fluoride) or polyester coating to match steel roofing panels and enhance UV/weather resistance.
Manufacturing Process:
- Cold Heading: Forms screw head and shank with integrated drill point.
- Thread Rolling: Creates self-tapping threads for metal penetration.
- Heat Treatment: Hardens drill tip and shank for durability.
- Coating: Electroplated zinc-aluminum or organic coatings (e.g., PVDF) applied via dip-spin or spray.
- Curing: Heat-treated to bond color coating to the surface.
Key Production Considerations:
- Drill Tip Geometry: Optimized angle (typically 90°–120°) and hardness to pierce steel sheets without pilot holes.
- Thread Design: Sharp, deep threads for fast driving and grip in thin metal.
- Coating Uniformity: Ensure consistent thickness to prevent rust and color fading.
- Sealing Washer: Integrate EPDM rubber or silicone washer for waterproofing.
Applications:
- Roofing: Fasten color-coated steel sheets in industrial, agricultural, and commercial buildings.
- Siding: Secure wall panels in warehouses, garages, and prefab structures.
- Solar Mounting: Attach solar panels to metal frameworks.
- Cold Storage: Assemble insulated panels in refrigerated facilities.
Installation:
- Tool Setup: Use a cordless drill with a hex-head driver bit (typically #2 or #3).
- Alignment: Position screw perpendicular to the metal surface.
- Driving: Apply moderate pressure; the self-drilling tip will pierce the metal and form threads.
- Stop Point: Tighten until the EPDM washer compresses fully, creating a watertight seal.
- Spacing: Follow guidelines (usually 12–24 inches apart) to prevent panel buckling.
Advantages:
- Time-Saving: Eliminates pre-drilling and tapping steps.
- Weatherproof: Sealing washer prevents leaks and corrosion.
- Aesthetic: Color-matched finish blends with roofing panels.
Note:
- Avoid over-tightening, which may strip threads or damage the coating.
- Replace screws with worn drill tips or cracked washers.
- Use stainless steel screws in coastal or chemically aggressive environments.
Frequently Asked Questions
A: Normally, we make a 30% deposit after Pl confirmation and a 70% balance before shipment. lf order amountis too small, we can also change to 100% deposit in order to save bank handling charge.
A: A pre-bulk sample check can solve this problem to the largest extent. We will arrange production according to the pre-bulk sample quality standard after your confirmation of the samples.
A: We are not only a trading company but also a manufacturer. Our factory mainly focuses on mold design and quality inspection. Our bulk production may come from the factories we have worked with for a long time, and they are all ISO9001 certified. Through this cooperation model, we can not only ensure product quality and service, but also satisfy the diversified product needs of customers, and the price is more advantageous.
A: Yes,we are very glad to offer you samples.
However the express courier cost from our company to your required address will be upon your account.
Usually we use DHL, UPS, FEDEX or EMS as the courier.
It will take 3-7 days to arrive many Europe countries and North America.
Which express courier we will use, it’s up to your convenient or the express charge.
A: No,just part of our capable categories have been showed in our site.
If you are looking for relative industrial products, please feel free to contact us.
Get Quote Now!
Welcome to discuss your purchasing requirements with our customer service.
