Mobile cranes are covered by the most detailed inspection regime of any plant on site. AS 2550.1 and AS 2550.5 require routine, periodic and annual inspections, and a major inspection at the end of the crane's design working period — ten years for most mobile cranes — before it can continue in service. Cranes over 10 tonnes rated capacity must also hold design and item registration under the WHS Regulations.
We carry out annual and major inspections of slewing and non-slewing mobile cranes, including franna-type pick-and-carry cranes, all-terrain and rough-terrain cranes and crawler cranes, and report in the form required for the crane log book and plant register.
Inspection checklist areas
- Boom and jib structure
- MT of boom section welds, pivot and cylinder mounts, lattice chord and lacing welds on crawler cranes; telescopic section wear pads, rope and pin retention; fly jib stowage and pins.
- Slew ring, superstructure and carrier
- Slew bearing clearance and bolt condition, superstructure and counterweight mounts, outrigger beams, boxes and pads, carrier chassis welds, suspension lock-out.
- Hoist, wire rope and hook
- Rope condition to AS 2759 discard criteria (broken wires, wear, corrosion, deformation), rope termination and drum anchorage, hook throat opening, wear and latch, hook block sheaves and bearings.
- Safety devices
- Load moment indicator calibration and function, anti-two-block, hoist and boom limits, slew and outrigger interlocks, level indication, audible and visual alarms.
- Hydraulics and controls
- Cylinder holding valves, hose condition, control function and free-fall lockout, emergency lowering.
- Documentation and registration
- Design and item registration status, log book entries, load charts matching configuration, previous annual and major inspection records.
Known failure modes
Boom structural failure
Fatigue cracking at boom pivot, cylinder mounts and section welds, or lattice chord damage on crawler booms, often after unrecorded overloads or side-loading.
Overturning
LMI override or inaccuracy, outrigger ground failure, or pick-and-carry on slopes beyond the chart.
Wire rope failure
Rope run to broken-wire, corrosion or crushing discard limits, or rope damage at the drum and sheaves.
Slew ring failure
Bolt fatigue or bearing wear allowing superstructure separation under load.
Hook or block failure
Cracked hook, worn throat, missing latch or seized sheaves.
Applicable standards and regulations
| Reference | Title | Relevance |
|---|---|---|
| AS 2550.1 | Cranes, hoists and winches — Safe use — General requirements | Defines routine, periodic, annual and major inspections and record keeping. |
| AS 2550.5 | Cranes, hoists and winches — Safe use — Mobile cranes | Mobile crane inspection requirements, including major inspection at ten years. |
| AS 1418.1 and AS 1418.5 | Cranes, hoists and winches — General requirements; Mobile cranes | Design basis for assessing structure, safety devices and modifications. |
| AS 2759 | Steel wire rope — Use, operation and maintenance | Inspection and discard criteria for hoist and boom ropes. |
| AS 3775 and AS 3776 series | Chain slings and lifting components for Grade T chain | Where crane-supplied slings and components are included in scope. |
| Model WHS Regulations, Schedule 5 | Plant requiring design and item registration | Mobile cranes with rated capacity over 10 t require design and item registration. |
Inspection intervals
- Annual inspection
- At intervals not exceeding 12 months by a competent person (AS 2550.1).
- Major inspection
- At the end of the design working period — ten years for mobile cranes under AS 2550.5 — and thereafter at intervals set by the competent person conducting the inspection, based on assessed condition and duty.
When to inspect
- Annual inspection due
- Crane reaching ten years from manufacture or from the last major inspection
- After overload, contact with structures or powerlines, or overturning
- After boom, slew ring or outrigger repair
- Before purchase, hire or transfer to a new site
Frequently asked questions
What does a ten-year major inspection involve?
A detailed examination of the crane's structure and mechanisms, with disassembly to the extent needed to inspect critical components, NDT of critical welds and pins, examination of the slew ring, hoist and brakes, and review of the crane's history. It concludes with an engineering assessment of fitness for a further period of service and is documented in the log book.
Do pick-and-carry cranes have the same requirements?
Yes. Articulated pick-and-carry cranes are mobile cranes under AS 2550.5 and require annual and major inspections. Their articulation joint, tilt and stability systems and the load chart de-rating for travel on slopes are specific inspection points.
How is wire rope condition assessed?
Against the discard criteria in AS 2759 and the crane manufacturer's requirements: broken wire count per lay length, diameter reduction, corrosion, kinks, crushing, birdcaging and heat damage, plus termination and drum condition.
Is registration checked during the inspection?
Yes. Design registration and, for cranes over 10 tonnes, item registration are verified against the crane's identification plate and documents, and any gaps are reported as compliance findings.