ISO 9927-6:2016 Jib Crane Inspection Procedure Explained
ISO 9927-6:2016 "Cranes — Inspections — Part 6: Inspection procedures for jib cranes" is the dedicated standard governing jib crane inspections. It specifies the scope, methods, and acceptance criteria for daily, periodic, comprehensive, and special inspections of jib cranes, including portal base masts, deck-mounted units, and floating cranes.
Inspection Classification and Daily Checks
Jib crane inspections are organized into four levels. Daily inspections are performed by the operator before each shift, covering boom exterior condition, luffing and hoisting wire ropes, lifting spreaders, limit switches, load moment limiter (LML) self-test, anemometer reading verification, and slewing bearing gear lubrication status — typically taking 20–30 minutes. Periodic inspections are carried out monthly by maintenance personnel, including MPI of boom structural welds, detailed checks of all mechanisms, and lubrication — usually taking half a day to a full day. Comprehensive inspections are conducted annually by certified inspectors, involving non-destructive testing, load tests, and a full slewing bearing examination — spanning 2–3 days. Special inspections are triggered after installation, retrofit, an accident, or exposure to high winds (≥8 on the Beaufort scale) or an earthquake, with in-depth examination of the affected components. Compared to overhead and gantry cranes, jib cranes add unique inspection items for the boom steel structure, slewing bearing, and wind anchoring system.
Key Points of Periodic Inspection
For boom structural welds, MPI is performed using a magnetic particle flaw detector on all load-bearing welds at the boom root, luffing hinge lugs, wire rope attachment lugs, and boom section splice joints. Before inspection, paint is removed from the weld surface down to bare metal, with a magnetic yoke spacing of ≤100 mm. Boom member deformation is measured with a theodolite or total station, with lateral bow limited to ≤1/1000. The slewing bearing is checked for gear lubrication, ensuring no dry running or spalling, and bolt pre-tightening torque is re-tightened to within ±5% of the design value with no radial or axial play. The luffing wire rope is measured for diameter at multiple points along its full length, with wear limited to ≤7%. Brake linings must not wear beyond 50% of original thickness, and limit switches must trigger accurately at both upper and lower travel limits. Rail clamp jaw wear is limited to ≤0.5 mm, and tie-bar tension is verified by measuring mid-span deflection, which must not exceed 2%–3% of length. Kelude is equipped with certified inspectors and a full suite of inspection instruments.
| Inspection Point | Daily Inspection | monthly inspection | Annual Inspection | Method |
|---|---|---|---|---|
| Boom Structure | Visual Condition/Deformation | Weld Seam MPI | UT+MPI | flaw detector |
| Luffing Wire Rope | wire break/Lubrication | diameter measurement | EMT | Caliper/EMT |
| Slewing Bearing | Tooth Surface/Abnormal noise | Clearance/Bolt Torque | Full Disassembly | feeler gauge/Wrench |
| Luffing mechanism | Functionality | Brake/limit switch | Comprehensive Test | Thickness Measurement/Load Application |
| Wind Anchor | Rail clamp Condition | Jaw Opening/Cable Tension | anchoring Cable Tension Test | feeler gauge/tension meter |
Inspection Record Management
Daily inspection logs must record results and anomalies in the operation log each shift and be retained for at least 3 months. Monthly inspection reports should format data on weld inspection results, wear amount measurements, and functional check conclusions, with records kept for a minimum of 3 years. Annual inspection reports, including non-destructive testing raw data, load test data, and torque calibration data, must be retained for at least 3 years after the crane is decommissioned. Special inspection reports are kept for a minimum of 5 years post-scrapping. A digital management system is recommended to upload records to the Cloud Platform in real time, automatically remind users of upcoming inspection dates, and enable trend analysis across multiple inspection cycles to detect performance attenuation early. Kelude Heavy Industry offers annual and special inspection services for jib cranes and boom cranes in accordance with ISO 9927 Cranes — Inspections.
| Record Type | Interval | Retention Period | Format |
|---|---|---|---|
| Daily Log | Per Shift | ≥3Months | Paper/Electronic |
| monthly inspection Report | Monthly | ≥3Year | Form+Photograph |
| Annual Inspection Report | Annually | Scrapping+3Year | PDF+Raw Data |
| Special Report | On Demand | Scrapping+5Year | Standalone File |
Frequently Asked Questions
Q: What does a daily inspection of a jib crane cover?
A: Visual checks for boom skin deformation, luffing and hoisting wire ropes, hook rotation smoothness, load moment limiter self-test, anemometer reading, and slewing bearing teeth. Daily inspection takes roughly 20–30 minutes.
Q: What are the key points of a monthly inspection?
A: MPI of all boom weld seams (including the full weld at the root hinge lug splice), straightness within 1/1000, slewing bearing clearance and bolts, luffing wire rope diameter wear not exceeding 7%, and brake lining wear not exceeding 50%.
Q: What does the annual comprehensive inspection involve?
A: Full UT and MPI coverage, load tests at 100% and 110%, five-point calibration of the load moment limiter within ±5%, and slewing bearing disassembly inspection every 5 years or 10,000 hours. The inspector signs off on the results.
Q: When is a special inspection required?
A: After installation or retrofit, after an overload or collision event, or following strong winds (≥8 on the Beaufort scale) or an earthquake. Kelude offers both annual and special inspection services for jib cranes.
