Steel Beam / Girder Coupler
A beam clamp for scaffolding fixes a scaffold tube directly onto the flange of a steel beam. When a scaffold has to be built off structural steel, an I-beam, an H-beam or a girder, a normal coupler cannot grip the flat flange. The beam clamp can: one side clamps the beam flange, the other holds a Ø48 scaffold tube. Lengge makes the drop forged version for 48.3 mm tube, made to BS1139 and EN74, with a screw-adjusted jaw that fits a range of flange thicknesses.
We hold beam clamps in bulk, galvanized or painted, and ship by the thousand, factory-direct for scaffold contractors, steel erectors and dealers worldwide.
| Item | Specification |
|---|---|
| Type | Beam / girder clamp (tube to flange) |
| Grips | Steel beam flange (I-beam, H-beam, girder) |
| Flange fit | Screw-adjusted jaw, fits a range of flange thicknesses |
| Tube side | 48.3 mm (Ø48) scaffold tube |
| Tube connection | Fixed or swivel |
| Bolts | Clamp screw (flange) and T-bolt (tube) |
| Material | Drop forged steel |
| Standard | BS1139 / EN74 |
| Finish | Hot-dip galvanized or painted |
Tube size, jaw range and finish can be set to your specification. Confirm the beam flange your job uses so the clamp covers it.
A beam clamp for scaffolding fixes a scaffold tube onto the flange of a steel beam. When a scaffold is built off structural steel, an I-beam, an H-beam or a girder, the standards have to attach to the steel rather than stand on the ground. The beam clamp grips the beam flange on one side and holds a scaffold tube on the other. It is also called a girder coupler or a girder clamp.
A normal coupler grips round scaffold tube on both sides. A beam clamp grips a flat steel flange on one side and tube on the other. That is the key difference: the beam clamp is the only fitting in the range made to hold onto a beam flange, which is what lets you tie a scaffold to structural steel.
The jaw is adjustable. A clamp screw sets the opening to the flange, so one clamp fits a range of flange thicknesses across different beam sizes. Tell us the beams you work with and we confirm the clamp covers them.
A fixed girder coupler holds the tube at a fixed right angle to the beam, for standards rising straight off the steel. A swivel girder coupler lets the tube rotate to any angle, for braces or tubes that meet the beam on a slope. Pick the fixed type for uprights and the swivel for angled tubes.
The tube side fits Ø48 scaffold tube, the standard size, and the clamp is made to BS1139 and EN74. So it works in standard tube-and-coupler scaffolds and ties them to steelwork. Tell us your tube size if it differs and we confirm the fit.
Yes, the beam clamp is a load-bearing fitting, made to carry the scaffold load into the steel beam, which is why the forged body and the flange grip matter. We supply in bulk, galvanized or painted, and ship by the thousand; large or custom orders we confirm at the time.
Most scaffolds stand on the ground or cantilever off a concrete frame. But sometimes the scaffold has to attach to steel, a beam, a girder, a steel-framed structure, and a normal coupler will not grip a flat flange. The beam clamp is the fitting that solves it. This page covers what a beam clamp does, how it differs from a normal coupler, the fixed and swivel versions, and how the flange grip and loading work.
A beam clamp, also called a girder coupler, ties a scaffold tube to the flange of a steel beam. One side is a jaw that closes onto the flange with a clamp screw; the other side is a coupler that holds a scaffold tube. With the clamp fixed to the beam, the scaffold standards can rise off the steel, and the load from the scaffold runs back into the beam. It is how you scaffold a steel-framed building, hang an access platform under a bridge girder, or work off any structure where the steel, not the ground, carries the scaffold.
The difference is what each one grips. A double or swivel coupler grips round scaffold tube on both sides. A beam clamp grips a flat steel flange on one side and tube on the other. That flange jaw is the whole point: it is the only fitting in the coupler range built to hold onto structural steel, so it is what bridges a tube scaffold to a steel beam.
Beam clamps come with the tube connection either fixed or swivelling, and the choice follows how the tube leaves the beam:
| Type | Tube connection | Best for |
|---|---|---|
| Fixed girder coupler | Tube held at a fixed right angle to the beam | Standards rising straight off the beam |
| Swivel girder coupler | Tube rotates to any angle | Braces and tubes meeting the beam on a slope |
For standards going straight up off the beam, the fixed type holds the tube square. For braces or any tube that meets the beam at an angle, the swivel type lets you set the angle. A job on steelwork usually needs some of both.
The jaw is adjustable so one clamp covers a range of flange thicknesses, set with the clamp screw on site. Two things decide whether it is safe: the jaw has to fully seat on a sound, clean flange, and the clamp has to be rated for the load it carries into the beam. A beam clamp is a load-bearing fitting, so check the safe working load against the scaffold load at that point, and make sure the flange itself can take the reaction. Where the load is high, more clamps or a check by the temporary-works engineer is the right call.
The tube side fits 48.3 mm scaffold tube, and the clamp is made to BS1139 and EN74, so it works with standard tube-and-coupler scaffolds. Finish is hot-dip galvanized for outdoor and long-cycle work or painted for shorter use. Galvanizing earns its place on beam clamps in particular, because they often sit on exposed steel and bridges, and a galvanized clamp screw still turns freely when it is time to strip the scaffold.
Confirm the beam flanges your job uses so the jaw range covers them, the tube size on the coupler side, the fixed or swivel tube connection, and the finish against the site. Beam clamps are bought in bulk like the rest of the coupler range, so check the supplier holds volume and can ship by the thousand without the price per piece rising on a large order.
