Buy Wedge Lock Washers Online in Australia
Wedge Lock Washers for Australian Vibration-Resistant Bolted Joints
Wedge lock washers are pairs of washers with cam-form internal faces that lock together when the bolt is tightened — providing vibration-resistant bolted joints that conventional spring lock washers can't reliably deliver. For Australian engineering, heavy machinery, mining equipment, and any application where bolted joint loosening creates safety or performance issues, wedge lock washers are the engineered solution. AIMS Industrial supplies Nord-Lock wedge lock washers and equivalent products across the standard sizes and materials.
How wedge lock washers work
Wedge lock washers come in matched pairs. The faces that contact each other have radial cams (like teeth on a saw blade) at a specific angle. When the bolt is tightened, the cam faces lock together — and the cam angle is steeper than the bolt's thread helix. This means any rotation that would loosen the bolt requires the cam faces to ride over each other (taking the bolt with them in the tightening direction). The geometry mechanically prevents loosening from vibration. To remove the bolt, the cam pair must be deliberately broken loose — applied torque overcomes the cam lock.
Why wedge lock over spring lock washers
Conventional split-ring spring lock washers provide modest spring force but limited rotation resistance. Under sustained vibration, spring lock washers can fully relax (squashed flat) and provide essentially no continuing locking function. Wedge lock washers don't rely on spring force — they rely on the cam geometry, which doesn't degrade in service. The result is a bolted joint that maintains its initial preload over years of operation, where spring lock washer joints may loosen within months in vibrating service.
Where wedge lock washers earn their place
- Heavy machinery — earth-moving, mining, agricultural equipment subject to constant vibration
- Wind turbines and rotating equipment — where bolt loosening creates serious safety risk
- Rail and transport — where dynamic loads are high and inspection access is limited
- Structural connections in vibrating environments — bridges, machinery foundations
- Critical safety fixings — anywhere fastener loosening creates injury risk
- Bolted joints subject to thermal cycling — engines, exhaust systems, process equipment
Nord-Lock — the established brand
Nord-Lock is the Swedish-engineered brand that pioneered the wedge-lock washer system. The Nord-Lock range covers metric sizes M3 through M48 and beyond, in standard zinc-flake-coated steel and stainless steel materials. The pair of washers ships pre-assembled and remains paired during installation — they're designed to be used together. For applications requiring documented compliance with vibration-resistance specifications, Nord-Lock provides certified test data.
Materials and finishes
- Zinc-flake coated steel — the everyday choice for indoor and protected applications
- Stainless steel 254 SMO — premium stainless for marine and aggressive corrosive environments
- Specialty alloys — for high-temperature and exotic-environment applications
Sizing
Wedge lock washers are sized to match the bolt — same nominal size as a standard washer for the same bolt. Common sizes range from M3 through M48 in metric, with Nord-Lock and equivalent products covering the full range. The washer's outside diameter is similar to a standard plain washer, so they fit existing bolt assemblies without modification.
Installation
Wedge lock washers install like any other washer. Place the matched pair under the bolt head or nut (the cam faces must contact each other; the smooth backs face the bolt and joint surfaces). Tighten the bolt to the specified torque — the wedge lock action engages automatically as the bolt comes up to torque. The pair must be replaced as a pair if disassembled; don't substitute single washers from different pairs.
Companion ranges at AIMS
Wedge lock washers sit alongside our broader fastener range — see Nord-Lock brand page, safety washers, Schnorr safety washers, and spring lock washers for the related products.
Need help speccing wedge lock washers for specific applications or vibration concerns? contact our team — we'll match by bolt size, material, and application requirements.