ISO 8686-5:2017 is an international standard that defines the design principles engineers must follow when calculating loads and load combinations for overhead travelling cranes and portal bridge cranes. It forms part of the broader ISO 8686 series, which provides a structured framework for ensuring cranes are designed to safely withstand operational forces throughout their service life.
Purpose of ISO 8686-5:2017
The primary goal of ISO 8686-5:2017 is to establish consistent engineering rules for determining the loads acting on crane structures and mechanisms. These rules help designers evaluate how cranes behave under different operating conditions such as lifting, travelling, acceleration, wind exposure, and emergency situations.
By standardising these calculations, the regulation ensures that cranes are designed with appropriate safety margins, reducing the risk of structural failure, fatigue damage, or unsafe operation.
Types of Cranes Covered
ISO 8686-5 specifically applies to:
- Overhead travelling bridge cranes
- Portal bridge cranes
- Gantry-style bridge crane systems
These cranes are commonly used in manufacturing facilities, warehouses, shipyards, steel plants, and container terminals, where heavy loads must be lifted and transported safely across large spans.
Key Design Principles and Load Types
The standard identifies several categories of loads that must be considered during crane design:
1. Permanent Loads
These include the self-weight of the crane structure, trolley, hoisting equipment, and any permanently attached components.
2. Operational Loads
Operational loads occur during lifting, lowering, travelling, and braking. These include the lifted load, dynamic effects from acceleration or deceleration, and inertia forces.
3. Environmental Loads
External forces such as wind loads, temperature effects, and seismic influences must be evaluated depending on the crane’s operating environment.
4. Exceptional Loads
These represent unusual or rare conditions such as impact forces, emergency stops, or accidental overloads.
The standard also explains how these loads must be combined in different scenarios, allowing engineers to verify structural integrity and mechanical reliability across the crane’s lifecycle.
Importance for Crane Safety and Compliance
Adhering to ISO 8686-5:2017 is critical for manufacturers, structural engineers, and safety professionals involved in crane design and certification. By applying the load calculation methods and safety factors outlined in the standard, organisations can ensure their crane systems meet internationally recognised engineering and safety requirements.
This helps improve operational reliability, protect workers and infrastructure, and support compliance with global lifting equipment regulations.
👉 For the complete technical specification and detailed calculation methods, consult the full ISO 8686-5:2017 standard published by the International Organization for Standardization here