Elco Flex® (Elco is now known as DeWalt) technology is a patented innovation in the field of fastening systems, originally developed by Gregg Melvin of Elco Construction Products. Elco is now a subsidiary of DeWalt which is part of the Stanley Black and Decker conglomerate.

Elco’s Flex technology is designed to provide high performance and durability in critical construction applications, especially with a focus on dissimilar metal connections (contact points), such as aluminum used with steel and/or stainless-steel. Dissimilar metals cause all sorts of structural issues including corrosion and possibly hydrogen embrittlement by reducing and preventing stress failures. They work by making the non-drilling portion of the fasteners more ductile (softer) than the drill point.

These Flex fasteners are most popular with curtainwall applications and also used in both wall cladding and façade applications. Elco Flex technology was specifically engineered to prevent corrosion and stress failures such as HASCC (hydrogen-assisted stress corrosion cracking), which can cause sudden and catastrophic fastener fractures. Flex technology is based on a dual-hardening process, which creates a unique bi-metal structure inside the metal making up the fasteners. The point and lead threads of the fasteners are hardened to a higher degree (HRC 52 min.) than the load-bearing threads (HRC 28-34). This allows the fasteners to drill and tap efficiently, while maintaining sufficient ductility and toughness to withstand high loads and stresses. The fasteners are also finished with a multi-layered, corrosion-resistant coating, called Stalgard®, which provides superior protection against rust and galvanic corrosion. Stalgard coating is environmentally friendly, free of chromates and silicates, and does not induce hydrogen embrittlement and is fully RoHS compliant.

Elco Flex technology was originally designed for use in self-drilling screws, but now is used in other types of fasteners, such as self-drilling screws, self-tapping screws, and concrete anchors, for different construction purposes. Some examples of Elco Flex technology products are:

• Dril-Flex®: Structural self-drilling fasteners that are virtually immune to hydrogen embrittlement and provide enhanced galvanic compatibility in dissimilar metal applications. These are very popular in curtainwall applications.
• Tap-Flex®: Structural self-tapping (thread forming) fasteners that are suitable for heavy gauge metal fastening, and feature a patented design that reduces installation torque and increases pull-out strength. Tap-Flex provide values approximating a Grade 5 bolt. Tap-Flex fasteners can even accept standard nuts and washers if needed.
• Alumi-Flex®: Stainless steel self-drilling fasteners that are designed for use only in aluminum.
• CreteFlex®: 410 Stainless concrete screws that are ideal for masonry fastening, and offer high pull-out and shear values. This is the go-to item for most customers working in concrete. They function much like Ultracon® and Tapcon® anchors.
• Aggre-Gator®: Bi-metal concrete screws that combine a 300 series stainless head and fuse it to a standard carbon lower portion. They are ideal for masonry fastening which offer high pull-out and shear values. They function much like Ultracon® and Tapcon® anchors.

Elco Flex technology products are tested and approved by various standards and organizations, such as ASTM, ICC, COLA, and FM. Elco Flex technology products are also backed by comprehensive engineering and technical support from DEWALT.

Elco Flex technology is a remarkable innovation that offers a reliable and cost-effective solution for critical fastening applications. Elco Flex technology products are designed to meet the highest standards of quality, performance, and safety, and to deliver superior results in demanding construction environments. Elco Flex technology products are not only good for the fastening, but also good for the future. Flex technology screws are just what YOU need to produce a high-quality job.

Some notes for those wanting more information: 

Hydrogen Embrittlement is introduced at the time of manufacture but doesn’t typically become evident until installed in the field. HASCC is environmentally introduced by galvanic reaction, especially (but not exclusively) in high-humidity and/or high-saline environments. All are caused by hydrogen, the most common source being H2O, or water which begins the process of electrolysis and galvanic reaction leading to corrosion and fastener failure.

Stalgard® coating is typically about 1000 hours of salt-spray before red rust, Stalgard Plus® is about 1500 hours, and Stalgard SUB® is around 2000 hours. Stalgard is full RoHS compliant and certified chrome-free.