Overview
ISO 11662-2:2014 - "Mobile cranes - Experimental determination of crane performance - Part 2: Structural competence under static loading" - defines a systematic, non‑destructive test method to verify the structural competence of mobile crane load‑supporting structures under specified static loads. The standard applies to common mobile construction‑type cranes including rope‑supported lattice booms, mast‑mounted booms, and telescopic booms, and uses resistance‑type electric strain gauges to measure induced stresses and set acceptance criteria.
Key topics and technical requirements
- Scope and applicability: Targets load‑supporting structures (not power‑transmission mechanisms) for mobile cranes such as lattice booms, mast attachments, fly jibs, and telescopic booms. Illustrative examples are in Annex E.
- Test method: Uses resistance‑type electric strain gauges to record strains under controlled conditions - including a zero/initial reference, dead‑load, working‑load and overload test conditions - enabling calculation of stresses.
- Loading procedures: Defines specific loading conditions (suspended load, side load, deflection criteria) and required test set‑up/conditioning (break‑in, block supports) to establish repeatable baseline readings.
- Stress evaluation and classification: Classifies structural areas into Class I (Uniform stress areas), Class II (Stress concentration areas), Class III (Column buckling areas) and Class IV (Local plate buckling areas) and specifies evaluation procedures and acceptance margins for each class (see Clause 10 and Annexes A–C).
- Data and reporting: Requires defined records, test procedures, and recommended report formats (informative Annex D), ensuring traceability and conformity assessment.
- Limitations and interpretation: Notes that in some cases analytical results may indicate more severe conditions; the standard allows substitution or addition of such conditions where justified.
Practical applications and users
- Mobile crane manufacturers use ISO 11662-2:2014 to verify and validate design assumptions, confirm manufacturing quality, and support product certification for the crane types illustrated.
- Test laboratories and inspection bodies implement the strain‑gauge test procedures to assess structural integrity before delivery or during periodic assessment.
- Fleet owners, rental companies and safety engineers rely on the standard to ensure cranes meet structural performance criteria under static loading and to interpret test reports against defined acceptance criteria.
- Design engineers can use test results to correlate and refine analytical models, particularly for buckling‑sensitive members.
Related standards
- ISO 11662 (Part 1: Tipping loads and radii) - complements this part by addressing stability tests and tipping limits.
- ISO 9373:1989 - referenced for accuracy requirements during testing.
Keywords: ISO 11662-2:2014, mobile cranes, structural competence, static loading, strain gauges, crane testing, boom testing, lattice boom, telescopic boom, stress evaluation, non‑destructive test.