Lifting equipment fails in two ways: gradually, through wear and fatigue, and suddenly, through overload or a defect that was present and invisible. A load test addresses the second and periodic inspection addresses the first; neither replaces the other, and a site that relies on one alone is exposed to the failure mode the other covers. This note sets out what each proves, how the two fit together, and what the records should contain.
A load test demonstrates that an appliance can carry a defined load at a point in time, under the conditions of the test. It is a proof of strength and stability, taken at commissioning, after a significant repair or modification, or at the interval local rules require. A static test applies a load above the rated capacity and holds it, checking for permanent deformation or movement; a dynamic test moves the load through the operating motions, checking the brakes, the hoists and the structure under working conditions. The test is a snapshot of capability, not a statement about condition, which is why it cannot substitute for inspection.
Inspection looks for the defects that a load test cannot reveal. The critical welds, the rope or chain, the hook and its latch, the brake lining, the sheave and drum, the limit switches and the structure are examined against acceptance criteria. Many of the defects that matter most - fatigue cracking at a weld toe, internal rope wire breaks, a hook throat that has opened - are not visible to an operator and would not fail a load test performed before they progressed to a dangerous size. That is precisely why the inspection regime exists on its own interval.
| Trigger | Load test | Periodic inspection |
|---|---|---|
| New installation or commissioning | Required | Required before first use |
| After significant repair or modification | Required | Required |
| In service, normal duty | At the regulated interval | At the regulated interval, more often for heavy or critical duty |
| Heavy, continuous or hazardous duty | Shorter interval | Shorter interval, driven by duty and environment |
| Idle or stored equipment | Before return to service | Before return to service |
The exact intervals are set by the rules that apply where the equipment is used; a duty-based adjustment up or down from the baseline is normal practice, and the reason for each adjustment should be recorded so the next reviewer can follow it.
An inspection that is not recorded cannot be trended, and a defect that is not recorded cannot be shown to have been closed out. Each entry should identify the appliance, the date, the inspector, what was checked, any defect found and its severity, the action taken, and the date the action was completed. Over several years that record shows how fast a given appliance is wearing and when its rope or brake lining is likely to need replacement - which converts inspection from a compliance duty into a planning tool.
No. A test proves the appliance can carry a load now; inspection finds the defects that will stop it later. They answer different questions and run on different intervals.
Duty cycle, environment and consequence of failure are the usual drivers. A crane lifting in a corrosive atmosphere, or one whose failure would endanger people, earns a shorter interval; the reasoning should be documented at the point it is set.
Classify it and act on the classification. A defect that affects safety takes the appliance out of service until it is rectified; a lesser defect is scheduled with a date and re-checked. The one thing that must not happen is a defect that is written down and then never given an owner.
Load testing, inspection and the records that tie them together are what keep lifting equipment trustworthy over its life. ZH Industrial Machinery supplies industrial cranes and the lifting hardware around them, and we can help a site align its test and inspection intervals with the duty its equipment actually sees.
Periodic inspection of lifting appliances exists because defects that matter are rarely visible, which is the province of non-destructive testing. The test methods an inspection regime cites are normally ASTM International standards, and the guarding and access duties around the appliance come from the US Occupational Safety and Health Administration.