An Introduction To Anchor Screw Bolts

In the video below, we discuss our anchor screw bolts as part of our concrete screws range; explaining how they are used and discussing specification details.

What is an Anchor Screw Bolt?

Anchor Screw Bolts, also referred to as Concrete Bolts or Thunderbolts, are used for heavy-duty applications. They offer the option to fix into materials like concrete, stone, brick, blockwork, and timber without using a plug.

The most common type has a hexagon head, which can be fastened with a spanner, socket, or impact driver.

Why should I use an Anchor Screw Bolt?

The main advantage of using an Anchor Screw Bolt is that they do not need a plug to be fitted, so they do not use expansion forces to stay fastened. Because of this, they can be used closer to the edge of the substrate than other fixings, and will not cause any damage to the substrate.

Anchor Screw Bolts can be fully removed if required.

What size drill should I use to install an Anchor Screw Bolt?

It’s important to install your fixings correctly, so make sure you use the right drill size for your Anchor Screw Bolt. As a general rule, the required drill size is 2mm less than the diameter of the bolt.

Please remember that the hole you drill into your fixture should be the same diameter as the screw bolt. For example, if you’re using a 12mm diameter bolt, you’ll still need a 12mm drill to penetrate the fixture, and then a 10mm drill for the substrate.

Anchor Screw Bolt Types

We stock three different types of Anchor Screw Bolts: Countersunk Head, Hexagon Head, and Flange Head.

Countersunk Head Anchor Screw Bolts are available in 75mm length, in either 8mm or 10mm diameter. The required drill size for these is therefore 6mm and 8mm, respectively. They are metric and are made of high-quality Steel.

Our Hexagon Head Anchor Screw Bolts are available in lengths from 75mm to 140mm and diameters from 10mm to 12mm. The required drill size for these is therefore 8mm to 10mm. They are metric and are made of high-quality Steel.

Our Flange Head Anchor Screw Bolts are available in lengths ranging from 50mm to 100mm and are 8mm in diameter. The required drill size for these is therefore 6mm. They are metric and are made of high-quality Steel.

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