Where your scaffold geometry requires a connection through or inside a scaffold tube bore, the Internal Hook Coupler from Altrad Generation provides a secure fitting that operates within the tube profile for applications where external couplers cannot be positioned.
Available as part of the complete scaffold fittings range, internal hook couplers work alongside external hook couplers, double couplers, and the full range of scaffold fittings for complex scaffold configurations.
Internal Hook Coupler Applications
Connections where external coupler access is restricted by scaffold geometry
Handrail and ancillary tube attachments requiring an internal tube bore connection
Specific scaffold configurations where the external profile must remain clear
Compatible with 3.2mm scaffold tube and 4.0mm scaffold tube bore dimensions
Available for hire and sale from Altrad Generation branches nationwide
Choosing Between Internal and External Hook Couplers
Select the connection type based on your scaffold geometry and design specification. The external hook coupler fits outside the tube for most sheeting and ancillary rail connections. The internal hook coupler inserts into the tube bore where external fitting is not possible. Both types are available from your local Altrad Generation branch.
Frequently Asked Questions
Q. What is an internal hook coupler?
A. An internal hook coupler fits inside the bore of a scaffold tube to connect a secondary tube to the interior of the primary tube. It provides a connection method in positions where external couplers cannot be fitted or where a flush external profile is required.
Q. Where is an internal hook coupler used in scaffolding?
A. Internal hook couplers are used for connections to scaffold tubes where external access is restricted, for attaching handrail tubes to scaffold standards through tube bores, and in specific scaffold configurations where the internal fitting geometry is required.
Q. What tube bore size does the internal hook coupler fit?
A. Internal hook couplers are designed to fit the bore of 3.2mm and 4.0mm scaffold tube. Check the product specification to confirm the internal bore dimensions for your specific tube grade and wall thickness.
Q. Is an internal hook coupler structurally rated?
A. Internal hook couplers are secondary fittings for ancillary connections. For primary structural connections between standards and ledgers, specify drop forged double couplers rated to BS EN 74-1:2005. Always follow your scaffold design specification for coupler type selection at each connection point.
Q. Are internal and external hook couplers interchangeable?
A. No. The external hook coupler clamps to the outside of the tube. The internal hook coupler inserts into the tube bore. The two types serve different connection geometries and are not interchangeable. Your scaffold design specifies which type is required at each connection point.
Contact your local Altrad Generation branch to discuss internal hook couplers and scaffold fittings, or find your nearest branch using our branch locator.
