ISO 9927-5:2016 Mobile Crane Inspection Procedure Explained

Inspection Classification and Intervals

ISO 9927-5:2016 classifies mobile crane inspections into four categories: Daily Inspection — performed by the operator before each shift, using visual checks and operational feel to verify the basic condition of crane systems; Periodic Inspection — conducted monthly by dedicated maintenance personnel, covering all systems thoroughly with specialized tools and measuring instruments; Thorough Examination — carried out annually by a certified inspector, including non-destructive testing and load tests; and Special Inspection — required after installation, overhaul, retrofit, or an incident, focusing on specific systems or structural components.

Daily inspections cover: Visual inspection — checking for visible damage and confirming hydraulic oil and coolant levels are normal; Functional checks — verifying smooth operation of all mechanisms, proper braking system and safety device function; and Safety checks — confirming the Emergency Stop Button, load moment limiter (LML), and alarm devices work correctly, and that tires or tracks are in good condition. Monthly inspections include: Structural component checks — inspecting weld seams and bolt torque on the main girder, boom, outriggers, and slewing bearing connections; Hydraulic system checks — looking for hose leaks, monitoring oil temperature, and checking filter elements; Electrical system checks — measuring cable insulation resistance, verifying controller and sensor function; and Wire rope inspection — performing diameter measurements and counting wire breaks.

Daily Inspection Checklist

The standard details the specific items and requirements for daily inspections, which the operator must complete before starting work using a checklist: Boom condition — telescopic boom shows no bending or deformation, and pin connections are secure; Outrigger system — outriggers extend and retract smoothly, and hydraulic lock valves function reliably; Hoisting mechanism — wire rope is spooled neatly, the hook safety latch is intact, and limit switches operate correctly; Slewing mechanism — slewing bearing produces no abnormal noise, and slewing brake function is normal; Travel mechanism — tire pressure or track tension is adequate, and the braking system works properly.

Any abnormalities found during the daily inspection must be recorded in the crane's operation log, including the description of the issue, time of detection, and corrective action taken. Minor faults that do not affect safety can be scheduled for repair after the day's work, while any safety-critical fault requires immediate shutdown and reporting for service. The daily inspection must be completed and signed off before the first lift of the day; the crane may not be operated until the inspection is passed. Inspection records must be retained for at least 3 months.

Periodic Inspection & Thorough Examination

Monthly periodic inspection content requirements per the standard cover structural weld seam checks—critical welds on the main girder and boom are examined using Magnetic Particle Inspection (MPI) or dye penetrant testing, with emphasis on high-stress zones and weld intersections. Connection bolts, including slewing ring bolts and boom connecting pins, are re-torqued and verified with a torque wrench against specified pre-tightening torque values. Gearbox lubrication is checked for oil level, oil condition, and breather vent functionality. Brake inspections confirm that brake lining wear does not exceed 50% and that brake clearance remains within the specified range.

Annual thorough examination content requirements include non-destructive testing of the boom and main girder structures using ultrasonic or magnetic particle methods, covering all critical weld seams and stress concentration areas. Hydraulic system pressure testing verifies maximum system pressure and safety valve set-point calibration. A comprehensive load test is conducted at 100% and 110% of rated load, combining hoisting, luffing, and slewing operations to validate overall structural integrity and safety device performance. The thorough examination report must be signed by a certified inspector and stamped with the inspection agency's official seal.

Special Inspections & Record Keeping

Special inspections are required under the following circumstances: after equipment installation or relocation to a new site (structural connection verification and functional testing), after major overhaul or retrofit (thorough examination of modified areas and related systems), following an accident or abnormal event (detailed inspection and assessment of damaged areas), and before recommissioning after prolonged shutdown (inspection of equipment idle for 3 months or more prior to restart). Each special inspection requires a site-specific inspection plan that defines the scope, testing methods, and acceptance criteria.

Kelude Heavy Industry offers mobile crane inspection services in accordance with ISO 9927-5:2016, staffed by certified inspectors equipped with professional testing instruments—including ultrasonic flaw detectors, magnetic particle flaw detectors, load testing systems, and wire rope inspection detectors—and issues nationally recognized inspection reports.

Frequently Asked Questions