Buy U-Bolts Online in Australia
U-Bolt Selection — Quick Reference
U-bolts secure pipes, cables, structural members, suspended equipment around bars + tubes that don't accept conventional bolting. Selection turns on bend type (round bend / square bend / J-bolt), inside dimension (matches held component), thread length, and material (galv vs SS).
| U-Bolt Type | Best For | Common Material |
|---|---|---|
| Round Bend (Round Bar) | Pipe + round bar mounting — standard plumbing + structural | Galv / Zinc / 304 SS / 316 SS |
| Square Bend (Square Bar) | RHS + SHS tube + square sections | Galv / Zinc / 304 SS / 316 SS |
| J-Bolt (Half-U) | Anchoring to wall + single-side fixing | Galv / Zinc |
| Threaded Both Ends with Mounting Plate | Complete kit — bolt + plate + nuts | Galv / SS — pre-matched components |
| Vehicle Suspension U-Bolt (Grade 8) | Leaf spring to axle — vehicle + trailer suspension | Heat-treated alloy steel |
| Marine U-Bolt (316 Stainless) | Boat + marine fittings — chloride exposure | 316 stainless steel |
| Heavy-Duty Threaded (M16+) | Heavy structural — large pipe + structural sections | Galv / hot-dip galv for outdoor |
Sizing rule: Inside dimension must match the OD of the component being held (round bar nominal + 1-2mm clearance for pipe). Thread length determines clamping range against mounting plate thickness. Material: zinc/galv for indoor + dry; hot-dip galv for outdoor + light corrosion; 304 SS for general corrosion; 316 SS for marine + chemical + chloride. Vehicle U-bolts: ALWAYS replace as a set (not single) + retorque after first 100km — leaf spring beds in + bolts can loosen. Companion: all fasteners, bolts, eye bolts, anchors.
U-Bolts for Australian Pipe Mounting, Suspension and Structural Fastening
U-bolts are the U-shaped threaded fasteners used to secure pipes, cables, structural members, and suspended equipment around bars, tubes, and other components that don't accept conventional bolted fastening. The U-shape passes around the held component, with both threaded ends extending through a mounting plate where nuts secure the assembly. For Australian plumbing, vehicle suspension, structural, and industrial mounting applications, U-bolts are essential. AIMS Industrial supplies U-bolts in metric and imperial sizes across the materials and bend types Australian customers use.
The U-bolt types we stock
- Round-bend U-bolts — semicircular bend; for round pipe and tube mounting
- Square-bend U-bolts — rectangular bend; for square section, channels, and rectangular tubes
- Long-shank U-bolts — extended threaded shanks for thicker mounting plates
- Heavy-duty U-bolts — larger diameter for higher-load applications
- U-bolt assemblies — pre-matched U-bolt with mounting plate and nuts
Materials and finishes
- Galvanised steel — the standard for outdoor and corrosive environments
- Zinc-plated steel — for indoor and protected applications
- Stainless steel 304 and 316 — for marine, food-grade, and aggressive corrosive applications
- Black self-colour steel — for paintable applications and indoor structural use
Where U-bolts earn their place
- Pipe mounting — securing pipework to walls, ceilings, and structural members
- Vehicle suspension — leaf spring U-bolts secure axles to springs in trucks, trailers, agricultural equipment
- Cable and conduit support — large-diameter cable and conduit fastening
- Equipment suspension — hanging tanks, machinery, and equipment from structural members
- Marine and outdoor applications — stainless U-bolts in saltwater and corrosive environments
- Antenna and signage mounting — securing antennas and signs to poles
- Custom fabrication — wherever a wraparound fastening is needed
Sizing — match to the component being held
U-bolt sizing has two main dimensions: the thread diameter (the threaded shank size) and the inside dimension (the diameter of pipe or width of section the U-bolt fits around). Common metric thread sizes range from M6 through M30; inside dimensions range from 12mm through 200mm depending on application. Match both dimensions — undersized inside dimension can't fit around the component; oversized leaves the component loose in the U-bolt.
Working load capacity
U-bolt working load capacity depends on the thread size, material grade, and mounting plate stiffness. For structural applications, U-bolts are typically rated as a system (U-bolt plus mounting plate plus nuts) rather than as individual components. Manufacturer data sheets give the working load for specific configurations. For lifting applications, U-bolts must be rated lifting components and supplied with traceable documentation — generic structural U-bolts aren't rated for lifting use.
Vehicle suspension U-bolts
Leaf spring U-bolts for trucks, trailers, and agricultural equipment are typically supplied as matched assemblies with the bolt, top plate, and nuts pre-matched for the spring stack thickness. Re-torquing is standard practice for new installations — torque after first 100km of operation, then periodically to maintain the specified preload. Loose U-bolts on vehicle suspension cause spring shift and serious safety issues.
Brands stocked at AIMS
Hobson and Bremick cover the U-bolt range across the standard sizes, materials, and finishes. For specialty U-bolts (large dimensions, specific OEM patterns, vehicle-specific assemblies), sourcing through our distribution channels covers most options.
Companion ranges at AIMS
U-bolts sit alongside our broader fastener range — see turnbuckles, rope grips, cable and conduit saddles, and structural bolt assemblies for the related products.
Need help speccing U-bolts for pipe mounting, vehicle suspension, or structural application? contact our team — we'll match by thread size, inside dimension, and material.