Proof load testing is where paperwork meets physics. Before any new EOT crane, gantry crane, or goods lift carries production load, it must demonstrate — with weights on the hook — that it performs safely above its rated capacity. Here is what that involves and why your factory inspector will ask about it.
What the test actually is
After erection, the crane lifts a test load of typically 125% of rated capacity, holds it, and travels through its motions while engineers measure girder deflection at mid-span. The measured deflection must stay within the limits of IS 3177 (for EOT cranes) and IS 807 (for the structural design). The result goes into a test certificate signed by the manufacturer.
Why it matters legally
Under the Factories Act and Gujarat Factory Rules, lifting machines must be tested and examined before first use and periodically thereafter. Your factory inspector can demand the initial test certificate at any audit. Running production on an untested crane risks stop-work orders — and far worse if something fails.
What deflection tells you
Deflection is the girder's honesty test. A girder that sags beyond the code limit under 125% load is under-designed — no paint job hides it. This is why we publish deflection values in our technical offers and test every installation before handover, without exception.
Periodic testing: not once, forever
The initial certificate is the beginning. Lifting equipment needs periodic examination by a competent person — commonly every 12 months. Our service team performs these examinations on all crane makes, including equipment we did not manufacture, and maintains the documentation trail your auditors expect.
Due for a periodic test, or commissioning a new crane? See our testing and maintenance services or book an inspection.