Tube Clamps: The Most Versatile Solution?
What are Tube Clamps?
Tube clamps — also widely known as key clamps or tube fittings — are a system of ductile steel fittings that grip onto standard-diameter galvanised steel tube using grub screws tightened with an Allen key or ratchet key. No welding, threading, bending or special tools are required. The result is a modular, bolt-together tubular framework that can be assembled and reconfigured in minutes, making tube clamps one of the most versatile structural fittings on the market.
F.H.Brundle supplies a comprehensive range of tube clamp fittings compatible with all tube component systems including Key Clamp. Fittings are available for 26.9mm OD, 33.7mm OD, 42.4mm OD, 48.3mm and 60.3mm OD galvanised tube, supplied in 6.5 m lengths or cut to size. The range carries DDA (Disability Discrimination Act) compliance and meets Part M of the Building Regulations when used with 42.4mm OD tube as a continuous smooth handrail.
What are the choices when it comes to Tube Clamps & Key Clamps?
At F.H.Brundle, we offer an extensive selection of tube clamp fittings, galvanised tube and accessories. Fittings are available in a standard hot-dip galvanised finish for maximum corrosion resistance, and many fittings are also stocked in polyester powder-coated black (RAL 9005) or other RAL colours to suit architectural and design requirements. Fittings range from simple single-socket end caps and rail ends, through to multi-way crosses, adjustable elbows, swept tees, reducers, floor flanges, wall flanges and flexible joint fittings — providing a comprehensive system for almost any tubular structure.
| Feature Category | Key Benefit | Detail |
|---|---|---|
| No-Weld Installation | Skill-Free Assembly | Grub screws are tightened with a standard Allen key or ratchet key. No welding, threading, brazing or specialist labour required — any competent tradesperson can build a complete structure. |
| Compliance | DDA & Building Regulations Part M | The 42.4mm OD system provides a continuous smooth handrail meeting DDA requirements and Part M of the Building Regulations for access to and use of buildings. |
| Finish & Corrosion Resistance | Galvanised or Powder Coated | Hot-dip galvanised fittings are suitable for indoor and outdoor use. Powder-coated black or RAL colour options give a decorative, durable finish with additional weather protection. |
| Versatility | Endless Applications | From handrails and safety barriers to exhibition stands, goal posts, pergola frames, shelving, storage racks and playgrounds — tube clamps adapt to virtually any tubular construction task. |
| Adjustability | Flexible & Reconfigurable | Adjustable elbow fittings allow any angle from 25°–180°. Unlike welded or cast structures, a key clamp frame can be dismantled, extended or altered at any time, making it ideal for temporary or evolving installations. |
| Tube Sizes | Multiple Diameters | Fittings available to suit 26.9mm (A-tube), 33.7mm (B-tube), 42.4mm (C-tube), 48.3mm (D-Tube) and 60.3mm (E-tube) OD galvanised tube (equivalent to ¾”, 1″, 1½”, 1¾” and 2 1⁄3″ nominal bore). Reducing fittings allow mixed-diameter structures. |
| Compatibility | Universal System | F.H.Brundle tube clamp fittings are compatible with all mainstream tube component systems including Key Clamp, enabling mixing of components from multiple sources within the same structure. |
Where can Tube Clamps & Key Clamps be used?
The versatility of the tube clamp system means it genuinely covers almost every sector. Some of the most common applications stocked by F.H.Brundle include:
Safety & Access: Handrails and stair handrails are one of the principal uses — particularly in commercial and industrial premises where a DDA-compliant or Part M-compliant handrail must be provided quickly without structural welding. Mezzanine handrails, roof edge guardrail, loading bay barriers, machine guards and pedestrian safety barriers are all built daily from key clamp components. The inherent strength and rigidity of steel fittings gripping schedule-pipe tube means these structures easily exceed the loading requirements of BS EN ISO 14122 and BS 6180 for guardrails.
Construction & Industrial: Tube clamps are widely used to create temporary or permanent scaffold-style barriers, site safety fencing, warehouse pallet racking guards, column protectors and pallet gate surrounds. The ease of disassembly makes them particularly popular where layouts change frequently or equipment needs to be installed around the structure after fabrication.
Leisure & Sports: Goal post frames, tennis court surrounds, sports screens, concert staging, outdoor gym structures and play equipment all benefit from the lightweight yet robust nature of the tube clamp system. Where structures must be seasonal or temporary, key clamps are unrivalled.
Retail & Display: Shop fitting, display racks, clothing rails, shelving systems, exhibition stands and billboard supports are frequently constructed from tube clamps — a reflection of how easily the system can be built and dismantled between shows or seasonal refits.
Why are Tube Clamps so ubiquitous?
Three drivers are behind the sustained increase in demand for tube clamps and key clamp fittings:
(1) Compliance without complexity: As awareness of DDA obligations, Building Regulations Part M and workplace safety legislation (including the Work at Height Regulations and BS EN ISO 14122) has grown, so has demand for a handrail and guardrail solution that is provably compliant out of the box. The 42.4mm OD tube clamp system satisfies the smooth-continuous-handrail requirement in a single product selection, removing risk and design effort from the contractor or specifier.
(2) Speed and flexibility of installation: Because no hot work is involved, tube clamp structures can be erected in areas where welding is forbidden (food production facilities, healthcare, clean rooms, occupied buildings and fire-risk environments). An experienced operative can install a complete multi-bay handrail run, mezzanine guardrail or safety barrier in a fraction of the time of a welded equivalent — dramatically reducing labour cost and site disruption.
(3) Long-term value and sustainability: Hot-dip galvanised tube clamp fittings are inherently corrosion resistant, extending service life well beyond uncoated steel structures. Critically, the system is fully reusable: when a layout changes or a structure is decommissioned, fittings and tube can be dismantled and redeployed elsewhere, minimising waste and delivering a lower total cost of ownership compared to disposable or fixed fabrications.
How to buy.
Now you have a clear picture of the benefits and applications of tube clamps and key clamps, here is how to approach your purchase:
(1) Measure your run and identify your application. Begin by measuring the total length of handrail, guardrail or barrier you need to create. Sketch out the layout, marking any changes of direction, staircase angles, floor-to-wall transitions and post spacings. This plan will determine the number and type of fittings required. If you need additional support and guidance, we’ve created a calculator and design tool within Liveconfigurator.
(2) Choose your tube diameter. Select the tube OD that matches your application and compliance requirement. For DDA or Part M handrails use 42.4mm OD tube. For lighter-duty shop fittings, shelving or display frames, 33.7mm or even 26.9mm may be more appropriate. Heavy industrial barriers or outdoor goal post structures often suit 48.3mm OD.
(3) Select your fittings. Using your plan, identify the fittings you need: single-socket rail ends for terminating a run; single-socket tees for intermediate posts; elbows (fixed 90° or adjustable) for changes of direction; long-radius swept tees for handrail branches; floor flanges and wall flanges for post bases and wall connections; and adjustable joint fittings to follow staircases or raking slopes. Use the F.H.Brundle Tube Clamp Selector for guidance. You will also find a range of pre-assembled posts which will further reduce install and labour time.
(4) Choose your finish. Standard fittings are supplied in hot-dip galvanised finish — ideal for any application and ready to use. If aesthetics are a priority, select powder-coated black (RAL 9005) fittings and matching tube, or order galvanised components and paint to any RAL colour of your choice.
FAQs
F.H.Brundle provides an online Tube Clamp Selector tool which guides you through your application step by step, generating a component list. Alternatively, the Tube Clamps Application Guide (PDF) contains illustrated diagrams of standard configurations — handrail runs, staircase rails, guardrails, corner posts, wall returns — with fitting identification for each position. As a general guide, each post requires a floor flange or base fitting, a mid-rail tee fitting (if required), and a top rail coupling fitting; end posts need a rail-end fitting; corners need elbow or swept-tee fittings.
If you want something that will do the calculations for you and create accurate drawings, use our Liveconfigurator tool.
Yes — one of the key advantages of the tube clamp system is that structures are fully demountable and reassemblable. Loosening the grub screws with an Allen key releases the fitting from the tube, allowing components to be reconfigured or redeployed entirely. This makes tube clamps particularly cost-effective for temporary structures, seasonal installations, or any environment where layouts change over time — such as warehouses, exhibition halls, schools and sports facilities.
Absolutely. The standard hot-dip galvanised finish on both fittings and tube provides excellent corrosion resistance for external use in most environments. For highly corrosive or coastal environments, specifying powder-coated fittings over the galvanised base coat provides additional protection. Where a more refined external appearance is required, architectural powder-coated black tube clamp fittings are available from stock.
Yes. The F.H.Brundle tube clamp range is DDA (Disability Discrimination Act) compliant and meets Part M of the Building Regulations for smooth continuous handrail when the 42.4mm OD galvanised tube is used. The smooth cylindrical profile of the tube presents no obstructions to a user sliding their hand along the rail, fulfilling the smooth-graspable-handrail requirement. Always confirm with the relevant building control authority for your specific project.
F.H.Brundle stocks tube clamp fittings to suit five standard outside diameters: A-tube 26.9mm OD (¾” nominal bore), B-tube 33.7mm OD (1″ NB), C-tube 42.4mm OD (1½” NB), D-tube 48.3mm OD (1¾” NB) and E-tube 60.3mm OD (21⁄3″ NB). The most widely used size for handrails is C-tube 42.4mm OD, as it satisfies the DDA and Part M smooth-continuous-handrail requirement. Reducing fittings are available to combine different tube diameters within a single structure.
Yes — “tube clamp” and “key clamp” refer to the same type of steel grub-screw fitting used to join galvanised steel tube into a structural framework without welding. “Key clamp” is a widely used trade name, while “tube clamp” is the generic descriptor. F.H.Brundle’s tube clamp fittings are fully compatible with all Key Clamp and equivalent tube component systems.
