When you need to anchor into hard materials such as concrete, brick, or stone, Expansion Shields from Coburn‑Myers offer a trusted and robust solution. Built to withstand shear loads, side pressure, and vibration, these anchors deliver long-lasting hold in applications where standard fasteners simply won’t do.

What Are Expansion Shields?

An expansion shield is a masonry anchor made from durable materials like zinc alloy (also available in lead, coated metal, or nylon‑coated varieties). It consists of three integrated components—a tubular shield, a wedge-shaped nut, and a hollow cone—all held together by spring bands designed for controlled expansion.

Once inserted into a pre-drilled hole and engaged with a screw or bolt, the shield expands radially. This grips the walls of the hole tightly, creating a secure mechanical interlock through friction and wedging action. Coburn‑Myers offers both single‑piece and double‑piece tubular designs—double shields expand at both ends, distributing load more evenly along the anchor’s length and providing superior hold in soft or brittle masonry.

How Expansion Shields Work

1. Drill the hole into a masonry substrate, sized correctly for shield diameter.

2. Insert the expansion shield flush into the drilled hole.

3. Drive in the bolt or screw, which pushes the cone into the shield, forcing outward expansion.

4. Grip and tighten—the expanding shield secures firmly against the material walls, resisting pull‑out, vibrations, and lateral loads.

This method ensures a firm, vibration-resistant hold that’s reliable across a wide spectrum of applications.

Expansion Shield Types Offered by Coburn‑Myers

Coburn‑Myers carries 24 expansion shield SKUs in their catalog, all made of zinc alloy with plain finish; available in both single and double piece variants across common imperial sizes (¼ in through ¾ in).

• Single‑piece shields are suitable for general medium-duty anchoring applications.

• Double‑piece shields provide enhanced load distribution and are well-suited for high-vibration or side-loaded installations.

Each shield integrates a wedge-shaped nut and cone, secured by antipull‑out spring bands, ensuring consistent expansion and rigid anchoring performance.

Advantages of Coburn‑Myers Expansion Shields

Superior Load Holding & Reliability

Designed to work reliably even in brittle substrates, Coburn‑Myers shields provide a consistent grip that resists shear and lateral forces—thanks to controlled expansion and load distribution.

Versatility Across Applications

Whether you’re installing handrails, shelving, conduit supports, signage, or machinery mounting fixtures, these shields offer the flexibility to work in concrete, brick, or stone substrates with varying densities.

Vibration Resistant Performance

Double‑piece expansion shields maintain their anchor integrity when subject to repeated vibration or shifts in direction, thanks to expansion at both ends of the shield. Meanwhile, the zinc alloy construction ensures strength and corrosion resistance.

Quality You Can Trust

Coburn‑Myers has been a family‑owned leader in industrial fasteners since 1981. Their expansion shields represent decades of engineering expertise and rigorous quality control, offering superior durability and dependable performance across industrial, OEM, MRO, and construction sectors.

Support for Project Success

Aside from offering a wide selection of stock sizes and finishes, Coburn‑Myers’ knowledgeable staff can assist you in choosing the right shield type and size for specific substrates and loading conditions, ensuring every project is successful and safe.

Common Applications

• Commercial and industrial construction: anchoring equipment, fixtures, structural supports to masonry walls.

• Signage and infrastructure installations: mounting signs, lighting, handrails, or conduit to brick, concrete or stone substrates.

• Residential and architectural assemblies: securing railings, shelving, decorative fixtures or outdoor hardware.

• Utility, plumbing & HVAC support: fastening heavy-duty electrical boxes, HVAC lines, or conduit where reliable anchoring is critical.

Installation Best Practices

1. Select the correct size: match shield diameter to bolt or screw size and substrate; Coburn‑Myers offers a full range of imperial sizes from ¼‑inch to ¾‑inch.

2. Drill clean, accurate holes: proper hole preparation is critical—remove debris to ensure full expansion of the shield.

3. Use proper bolt length and torque: such that the cone fully engages without bottoming out.

4. Consider substrate type: for brittle or crumbly material, double‑piece shields are recommended.

5. Assess loads: for shear or side loading, double‑piece variants boost performance. Coburn‑Myers offers guidance based on load conditions and substrate.

Why Choose Coburn‑Myers for Your Expansion Shields?

• Expertise and heritage: a family-owned leader since 1981 providing high‑quality fasteners and personalized service.

• Extensive stock and customization: readily available expansion shields as well as a full advisory staff to help select based on performance needs and materials.

• Industrial-grade quality: each anchor is engineered from premium zinc alloy using precision manufacturing, ensuring consistent expansion and maximum holding strength.

• Versatility across industries: Coburn‑Myers shields serve diverse sectors—construction, infrastructure, OEM, oil/gas, water/wastewater, mining, and more.

Summary

Coburn‑Myers expansion shields deliver a reliable anchoring solution wherever screws or bolts must be securely installed in concrete, brick, or stone. With durable zinc alloy construction, single and double‑piece designs, and precise expansion mechanics, they offer unmatched grip, load distribution, and vibration resistance.

When quality, reliability, and expert support matter, Coburn‑Myers is the go‑to supplier for expansion shields engineered to power your installations with safety and strength.

For sizing, quotes, or specification assistance, contact Coburn‑Myers Fastening Systems to explore expansion shield options specific to your application.