Concrete Undercut Self-Tapping Anchor, Hex Flange Head (US)

Concrete Undercut Self-Tapping Anchor, Hex Flange Head (US) — Product Introduction

The concrete undercut self-tapping anchor (hex flange head, US type) is a post-installed mechanical anchor that achieves fixation by having its self-tapping threads cut directly into the concrete substrate. During installation, a dedicated impact wrench is used to screw the anchor into a pre-drilled hole; the thread flanks cut into the concrete and form a mechanical interlock, delivering high load-bearing capacity without any expansion stress. The hex flange head design allows a socket wrench to apply higher torque, while the ribs beneath the head prevent accidental loosening of the fastener. The product is suitable for both cracked and non-cracked concrete and carries a European Technical Assessment (ETA) with seismic and fire-resistance class ratings.

I. Product Features

• Self-tapping undercut anchoring mechanism: The anchor thread features a serrated geometry that cuts directly into the concrete hole wall during screwing, forming a threaded engagement with virtually no expansion stress generated.
• Hex flange head structure: The head is hexagonal with an integrated flange face, allowing installation with a socket wrench; the flange face increases the bearing area and evenly distributes the clamping force.
• Variable embedment depth design: The same anchor size supports multiple embedment depths to accommodate different load requirements and plate thickness conditions.
• No expansion stress: Because it does not rely on the expansion principle, smaller edge distances and spacings are possible, making it suitable for space-restricted anchoring points.
• Material and corrosion protection: Commonly available in galvanized steel or stainless steel (A4), suitable for both indoor and outdoor as well as damp environments.

II. Product Advantages

• Fast and efficient installation: Screwed directly in with an impact wrench, no hole cleaning required (for ceiling and floor vertical installation), completing fixation in a single operation.
• Fully removable: The anchor can be unscrewed, suitable for temporary fixing scenarios such as formwork support, and can be reused.
• High load-bearing capacity: The tight thread-to-concrete engagement provides high load capacity in both cracked and non-cracked concrete, and is ETA-assessed for use in seismic design zones.
• Good safety and reliability: Ribs beneath the hex head prevent loosening; certified under the European Technical Assessment with an R120 fire-resistance class.
• Adaptable to small edge distances and narrow spacing: The absence of expansion stress allows anchoring points to be placed near component edges, improving design flexibility.

III. Application Scope

• Pipelines and MEP installation: Routing of pipelines, suspended pipes, channel/strut systems, ventilation ducts, and fixing of building services facilities.
• Suspension and bracing systems: Strut channels for suspension systems, bracket base fixing, formwork, and temporary scaffold fixing.
• Curtain walls and building components: Curtain wall framing, dry-hung stone facades, and post-installed connections for bridges and staircases.
• Cracked and non-cracked concrete: Suitable for cracked concrete substrates, and also for similar substrates such as solid brick, hollow brick, and aerated concrete.
• Seismic and fire-resistance required scenarios: ETA-assessed for use in seismic load zones and applications requiring the R120 fire-resistance class.