Hex Washer Flange (HWF) Self-Drilling Screws
Product Description
Hex Washer Flange (HWF) self-drilling screws combine the functionality of a hex head screw with an integrated flange washer, creating a single-piece fastener solution. Designed for heavy-duty applications, these screws offer exceptional load-bearing capacity and vibration resistance. The flange washer eliminates the need for separate washers, simplifying inventory and installation while ensuring uniform load distribution across the joint surface.
| Parameter |
Specification |
| Material |
AISI 1018-1022 Carbon Steel |
| Case Hardness |
HV 550-800 |
| Core Hardness |
HV 300-450 |
| Carburizing Depth |
0.15mm |
| Torsional Strength (#10) |
80-85 kgf·cm |
| Torsional Strength (#12) |
100-110 kgf·cm |
| Attack Rate (#10, 4mm Thickness) |
22kg / 4.5s |
| Attack Rate (#12, 4mm Thickness) |
22kg / 5.0s |
| Available Sizes |
#10, #12; Length: 13mm-220mm (Customizable) |
| Finish |
Customizable to customer requirements (e.g., zinc plating, Dacromet) |
| Point Types |
#3, #4, #5 |
Applications
- Heavy structural steel connections
- Trailer and truck body manufacturing
- Agricultural equipment assembly
- Solar panel mounting systems
- Construction of industrial storage racks
Advantages
- The integrated flange washer provides a larger bearing surface, distributing pressure evenly to prevent material deformation.
- Eliminates the need for separate washers, reducing part count and installation time.
- High torsional strength and case hardness ensure reliable performance in high-torque and vibration-prone environments.
- The hex head design allows for secure engagement with standard tools, reducing the risk of slippage during installation.
- Customizable finishes and sizes make these screws suitable for diverse industrial and construction applications.
Features
- Integrated self-drilling point enables fast, clean penetration into metal substrates without pre-drilling.
- The one-piece flange design provides superior resistance to loosening caused by vibration and thermal expansion/contraction.
- Optimized thread design ensures strong grip in both thin and thick metal sheets, preventing pull-out.
- Consistent heat treatment ensures uniform hardness across the screw, preventing premature failure.
- The wide flange creates a weather-tight seal in roofing and cladding applications, enhancing water resistance.

FAQ
1. Are you trading company or manufacturer ?
We are manufacturer ,You can see the certification.
2. How long is your delivery time?
Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.
3. Do you provide samples ? is it free or extra ?
Yes, we could offer the sample for free charge but need pay the cost of freight.
4. What is your terms of payment ?
Payment<=1000USD, 100% in advance. Payment>=1000USD, 50% T/T in advance ,balance before shippment.