Screw Bolts

Screw anchors (or screw bolts) typically support loads ranging from 200kg to over 1,200kg, depending on the bolt size, embedment depth and the density of the substrate material (e.g. concrete, brick or block). Always refer to the manufacturer’s specifications for shear and tension ratings.

Allcon offers same-day dispatch on a wide range of screw bolts and fixings when you order before 11am. With stock ready to go and a logistics network built for speed, you can count on Allcon to keep your project moving without suffering delays or downtime.

• Function
  • Screw Bolt: Fastens directly into a substrate.
  • Nut: Used in conjunction with a bolt to clamp materials together.
• Thread Engagement
  • Screw Bolt: Threads directly into concrete or masonry.
  • Nut: Threads onto a bolt shaft.
• Materials
  • Screw Bolt: Steel or stainless steel, hardened for anchoring strength.
  • Nut: Typically steel, often paired with a washer and bolt.
• Pairings
  • Screw Bolt: Used alone, no nut required.
  • Nut: Requires a bolt and often a washer.
• Reusability
  • Screw Bolt: Not recommended for reuse for safety reasons.
  • Nut: Can generally be reused unless damaged or distorted.

• Design
  • Screw Bolt: Self-tapping, one-piece anchor with threads along the shaft.
  • Through Bolt: Requires a pre-drilled hole with a nut and washer on the opposite side.
• Installation Method
  • Screw Bolt: Directly driven into a hole—no need for expansion or resin.
  • Through Bolt: Inserted through the fixture and tightened with a nut.
• Load-Bearing Use
  • Screw Bolt: High load capacity, ideal for both temporary and permanent fixing.
  • Through Bolt: Suitable for permanent fixings with consistent high-load demands.
• Removability
  • Screw Bolt: Fully removable, but not recommended for reuse.
  • Through Bolt: Can be removed, but leaves more disruption in the substrate.
• Thread Coverage
  • Screw Bolt: Full-length thread engages directly with the substrate.
  • Through Bolt: Thread is only on the upper portion, used with a nut.
• Typical Applications
  • Screw Bolt: Formwork, brackets, racking, temporary structures.
  • Through Bolt: Structural fixings, heavy-duty anchoring, steel connections.

Yes, screw anchors are required when screwing into concrete or masonry. They provide the grip and holding power in hard or brittle materials that regular screws cannot. Without anchors, screws can:

• Loosen over time
• Pull out under load
• Cause damage or failure of the fixture

Screw anchors are critical for safely hanging shelves, signage, heavy equipment and more.

Screw anchors are not recommended for reuse. Once removed, the thread engagement with the substrate is compromised, reducing load capacity and safety. Use a new anchor in any load-carrying or structural application.