Knuckle Boom Lift Inspections & Certification
A knuckle boom — the articulating boom lift that folds at one or more joints to reach up and over obstructions — works its structure differently to any other EWP. Every reposition cycles the articulation knuckles, pivot pins and linkage arms, and it is precisely those joints that let the machine do what a straight telescopic boom cannot. This page is where you arrange independent inspection and certification for an articulating boom lift, carried out under AS 2550.10 for safe use and AS/NZS 1418.10 for the design framework the machine was built to.
Because the articulation joints are the machine's defining feature, they are also where wear and fatigue concentrate. An inspection of a knuckle boom gives specific attention to the knuckles, pins and bushes, the riser and linkage geometry, the slew ring, the platform rotator and levelling system, and the load-sensing and envelope-limiting systems the operator relies on when working up-and-over. Findings are recorded and defects rated by severity, so you know exactly what must be rectified before the next lift and what can be scheduled into planned maintenance. We work independently of every manufacturer, across all makes and models, Australia-wide as a mobile field service.
Built For
- Hire businesses keeping articulating boom fleets compliant and hireable
- Construction and maintenance contractors working up-and-over obstructions
- Facilities, council and infrastructure teams running knuckle booms
- Owner-operators of a single articulating boom lift
- Buyers and sellers needing an independent condition and compliance record
Equipment & Coverage
- Self-propelled articulating (knuckle) boom lifts
- Electric and bi-energy knuckle booms for indoor and mixed use
- Rough-terrain diesel knuckle booms
- Articulation knuckles, pivot pins, bushes and linkage arms
- Platform rotator, levelling and envelope-limiting systems
The Process
Confirm the machine & history
We record the make, model, configuration and age and review the logbook and prior inspection history, so the assessment is scoped to the actual machine — its joints, its duty and what has already been done — rather than a generic checklist.
Inspect the articulation joints
The knuckles, pivot pins, bushes and linkage arms are examined for wear, elongation, distortion and fatigue, because on an articulating boom these joints carry the load path through every fold and reposition and are where problems start.
Assess structure, slew & platform
The boom sections, riser geometry, slew ring, platform, rotator and levelling system are inspected, along with the hydraulic circuit and the load-sensing and envelope-limiting systems that keep the operator inside the machine's safe working envelope.
Test, certify & document
Function and, where warranted, load and stability testing verify performance, defects are rated by severity, and you receive the logbook entries and certification documentation the machine needs to return to service compliant.
Compliance & Standards
Articulating boom lifts are designed to AS/NZS 1418.10 and used, maintained and inspected under AS 2550.10, within the broader AS 2550 series. Routine and annual inspections keep the machine safe between deeper checks, and a major inspection falls due at the interval set by the relevant standard and equipment class — commonly 5-year or 10-year depending on equipment type and duty. The articulated geometry is why the inspection regime matters more, not less, on this class: a worn pin or elongated bush changes how the whole linkage carries load, and the effect compounds across multiple joints in a way a single-section telescopic boom never experiences. We reference the applicable standards generically, record only what has genuinely been inspected or tested, and work independently of any manufacturer so the assessment stays objective. Keeping the inspection record current is also what keeps the machine insurable and the duty holder defensible if an incident is ever investigated.
Why EWP Australia
- Articulation knuckles, pins and bushes assessed as the core of the scope
- Envelope-limiting and load-sensing systems checked, not just the structure
- Independent of all manufacturers — findings reflect the machine, not a sales agenda
- Severity-rated defect reporting that separates safety-critical items from wear
- One specialist for the inspection and any resulting repair and re-check
- Australia-wide mobile field service — we come to the machine
Knuckle Boom vs Telescopic Boom at a Glance
Both are boom-type EWPs inspected under AS 2550.10, but the articulating geometry shifts where wear concentrates — and where the inspection looks hardest.
| Class | How It Reaches | Best For | Inspection Emphasis |
|---|---|---|---|
| Articulating (knuckle) boom | Folds at one or more joints for up-and-over reach | Working over obstructions, tight sites, congested plant | Knuckles, pivot pins, bushes and linkage free play |
| Telescopic (straight) boom | Extends in a straight line for maximum outreach | Open sites needing height and horizontal reach | Boom sections, wear pads and extend/retract system |
| Electric / bi-energy knuckle boom | Articulating, compact classes for indoor and mixed use | Fit-outs, facilities and indoor structural work | Battery and drive systems alongside the joints |
| Rough-terrain diesel knuckle boom | Articulating, on axles built for unprepared ground | Civil, construction and external services work | Axles, oscillation and chassis see harder duty |
Figures are indicative of typical equipment classes, not a specific unit. Confirm exact specifications for any machine before hire or purchase.
Common Questions
What is the difference between a knuckle boom and a telescopic boom lift?
A knuckle boom articulates — it folds at one or more joints so the platform can reach up and over obstructions — while a telescopic boom extends in a straight line for maximum outreach. Both are boom-type EWPs inspected under AS 2550.10, but the articulating geometry means a knuckle boom's inspection puts particular weight on the knuckles, pivot pins, bushes and linkage arms, because those joints carry the load path through every reposition. If your machine is a straight telescopic unit, our boom lift inspection and major inspection pages cover it directly.
Why do the pins and bushes matter so much on an articulating boom?
Because they are the load path. Every time the operator repositions the platform, the articulation joints cycle under load, and wear in a pin or bush shows up as play in the whole linkage. Left unchecked, that play accelerates wear in the neighbouring joints and changes how the structure carries load. Inspecting for elongation, wear and fatigue at these joints — and measuring rather than guessing — is the heart of a knuckle boom inspection.
How often does a knuckle boom need a major inspection?
A major inspection falls due at the interval set by the relevant standard and equipment class — commonly 5-year or 10-year depending on the equipment type and how hard it is worked. Between majors, routine and annual inspections keep the machine safe and compliant. We confirm the correct interval for your specific machine rather than quoting a single universal figure, and we can plan the major so it lands at a point that suits your workload.
Do you inspect electric and rough-terrain knuckle booms?
Yes. We inspect articulating booms across the class — compact electric units used indoors, bi-energy machines, and rough-terrain diesel booms working outside on slab or unprepared ground. The core scope is shared, but the emphasis adapts: an electric unit's battery and drive systems get attention alongside the structure, while a rough-terrain machine's axles, oscillation and chassis see harder duty and are assessed accordingly.
Can you repair defects the inspection finds?
Yes. Where the inspection finds worn pins and bushes, structural cracking, hydraulic leaks or control faults, we can arrange the repair and re-check the machine so it returns to service in a certified condition. Handling the inspection and repair through one specialist keeps the documentation joined up — the record shows what was found, what was fixed and that it was verified afterwards.
Can you inspect our knuckle booms on site?
Yes. EWP Australia operates Australia-wide as a mobile field service, so inspections are carried out where your machines are based or working rather than requiring transport to a depot. To arrange an inspection, call 0416 689 689, or email info@ewpaustralia.com.au.
Use Our Free Calculators
Quick tools to help you plan, compare options, and assess compliance requirements.
National Infrastructure Support
Reliable fleet access and major inspection services for government, defence, and top-tier contractors.