5-Year Major Inspection

What the major inspection covers

A major inspection is a scheduled overhaul-level examination triggered at ten years for most EWPs, with intermediate structural inspections at five years for boom-type units under AS 2550.10. In practice the terms are often blurred on site, so the first thing our engineers establish is exactly which examination the machine is due for, based on its logbook history, hours and manufacturer schedule.

The examination reaches parts of the machine that are inaccessible during routine servicing. Booms are extended and articulated through their full range, covers and guards are removed, and safety-critical welds and pivot points are exposed for direct assessment. Where the manufacturer specifies component life limits, those components are identified and their replacement scheduled.

• Complete structural assessment of booms, risers, turntable and chassis interfaces
• Non-destructive testing of critical welds and highly-stressed members
• Wear measurement of pins, bushes, slew bearings and wear pads
• Hydraulic system pressure, holding-valve and cylinder integrity checks
• Review of the machine's logbook, service history and prior inspection records

Why five and ten years matter

Fatigue is cumulative and largely invisible. An EWP that has spent a decade in mixed hire, construction and utility work has absorbed millions of load cycles, thermal excursions and the occasional overload it was never reported. The major inspection interval exists because visual servicing alone cannot detect sub-surface fatigue cracking before it becomes structurally significant.

By stripping and testing at defined intervals, an owner converts an unknown risk into a documented condition. That documentation is what lets a machine legitimately continue past the point where insurers, principal contractors and regulators would otherwise treat it as suspect. A machine without a current major inspection is, for practical purposes, unhireable on a well-run site.

Our inspection methodology

We begin with a desktop review: the compliance plate, the original design registration where applicable, the manufacturer's inspection schedule and the full logbook. This tells us the machine's baseline and flags any gaps in its documented history that need resolving before we touch it.

On the machine, our technicians work to a written procedure specific to the make and model. Dimensional wear is recorded against manufacturer tolerances, not eyeballed. Where access allows, magnetic particle and ultrasonic methods are applied to the welds and members that carry the highest stress ranges. Every finding is photographed and logged against a physical location on the machine so the report is unambiguous.

Findings are graded. Not every observation is a stop-work defect; the value of an independent inspection is a proportionate, engineer-signed judgement about what must be rectified before return to service and what can be monitored. We separate the two clearly so owners are not forced into unnecessary spend, nor left running a machine that should be down.

Non-destructive testing within the major inspection

NDT is where the major inspection earns its name. Cracks that would be caught only after failure in a visual regime are routinely found at the sub-millimetre stage using magnetic particle inspection on ferromagnetic welds and ultrasonic testing to interrogate thickness and internal flaws. Our NDT is performed by technicians qualified to recognised certification levels and reported with the acceptance criteria stated.

Because NDT results feed directly into the structural verdict, we do not treat it as a bolt-on. The choice of method, the areas tested and the acceptance criteria are all decided by the responsible engineer as part of the inspection plan for that specific machine.

Hydraulic and control-system integrity

A structurally sound boom is only safe if it holds position under load. The major inspection verifies that holding valves, counterbalance valves and cylinder seals perform to specification through creep testing and pressure checks. We also confirm that emergency lowering, overload sensing and stability cut-outs function as the design intends.

Control-system faults discovered here are frequently the difference between a machine that merely looks compliant and one that will behave predictably in an emergency. These checks are documented alongside the structural results in a single report.

Recertification and documentation

On satisfactory completion, we issue an engineer-signed report and update the machine's records so the next major inspection date is unambiguous. Where defects are found, the report states precisely what must be done to achieve recertification, and we re-attend to verify rectification rather than accepting it on trust.

The deliverable is written to stand up to scrutiny from a regulator, an insurer or a court. That is the point of engaging an independent firm: the certificate carries the weight of a named engineer's professional judgement.