Through Bolt (Wedge / Sleeve Anchor)

A through bolt is an expansion anchor for concrete. You drill a hole through the fixture into the concrete, push the bolt in, and tightening the nut expands a clip or sleeve at the bottom of the hole so the anchor grips. Falcon Link TR supplies through bolts from Sharjah for brackets, rails and equipment.

What is a through bolt?

In UAE trade, "through bolt" usually means a wedge anchor or sleeve anchor that passes through the fixture. A wedge anchor has a threaded stud with an expansion clip. A sleeve anchor has a metal sleeve that expands over the bolt. Both give a firm fixing in solid concrete and are used for handrails, racks and equipment.

Through bolt sizes and lengths

Lengths and fixture thickness vary by maker. Check the data sheet for the depth the anchor needs, and send us the fixture thickness so we can pick the right length.

Wedge anchor, sleeve anchor or chemical anchor?

How to install a through bolt

1. Mark the fixing and drill through the fixture into the concrete at the right diameter.
2. Clean the hole of dust with a brush or blower.
3. Insert the bolt with the washer and nut, then tap it in until the washer touches the fixture.
4. Tighten the nut with a spanner or torque wrench until the anchor is set.

Which finish for UAE conditions?

Coastal air and salt shorten the life of plain zinc finishes, so choose stainless or galvanised for outdoor and seafront work.

Common mistakes

• Drilling the wrong diameter, so the clip cannot expand properly.
• Using the bolt too close to a slab edge.
• Leaving dust in the hole, which weakens the grip.
• Over-tightening until the thread strips.
• Using it in thin or poor concrete without engineering advice.

Spacing and edge distance

An expansion anchor pushes outwards on the concrete around it. If it is too close to an edge or to another anchor, the concrete can crack or break away. The minimum spacing and edge distance come from the maker's data sheet, so check it before marking out your holes.

Setting and checking the anchor

Tighten the nut until the anchor is set, and use a torque wrench where the specification gives a torque. After installing, give the fixture a firm push by hand. Any movement means the anchor has not set, and it should be removed and replaced.

When to call an engineer

For load-bearing fixings, overhead loads, balustrades and anything where failure could hurt someone, the engineer should specify the anchor type, size, depth and spacing. We can supply what they specify.

What to send us for a quote

• Bolt size (M8, M10, M12 or M16) and total length.
• The fixture thickness the bolt passes through.
• The finish: zinc, galvanised or stainless.
• The quantity and delivery area.

If you cannot tell whether your concrete is solid and sound, ask the engineer to check before drilling, because a bad hole in poor concrete cannot be repaired by tightening harder.

What to buy with through bolts

Pair through bolts with bolts, nuts and washers, wall plugs for lighter fixings and threaded rod for hangers. See all fasteners and fixings.

Request a quote

Send the bolt size, length, finish, quantity and the fixture thickness through our contact page.