Point loading occurs when a concentrated force is applied to a single, small contact area instead of being distributed across a broader surface. In rigging and lifting applications, point loading can cause equipment failure, load instability, or ground collapse if not properly managed.
Understanding point loading is critical for safe crane operations, proper rigging configurations, and hydraulic lifting systems.
When planning a lift, load distribution is everything.
If too much force is concentrated on one point (whether a hook, crane outrigger, or hydraulic cylinder) the result can include:
Proper rigging design ensures forces are evenly distributed and remain within rated capacities.
One of the most frequent examples of point loading occurs on crane hooks and hoist hooks.
Hooks are designed so that slings sit securely in the saddle, which is the curved load-bearing area. Problems arise when the sling shifts toward the tip of the hook.
This creates a concentrated load at the hook’s point instead of along the saddle.
Risks of hook point loading include:
Repeated improper loading—even at lighter weights—can gradually stretch or weaken the hook.
How to prevent hook point loading:
Point loading also occurs at the ground level.
When a crane lifts a load, the force transfers through the outriggers into the soil below. If the ground bearing pressure exceeds the soil’s capacity, the crane may sink or tip.
Modern cranes are often designed with smaller footprints to improve mobility. However, a smaller footprint increases pressure per square inch. That is why outriggers—and outrigger mats—are critical.
How outriggers prevent dangerous point loading:
Outrigger mats further distribute pressure to prevent localized ground failure.
Hydraulic cylinders and rams are powerful lifting tools, but they often have a small base footprint relative to their capacity.
This creates high surface pressure beneath the cylinder.
If the supporting surface cannot handle that pressure, it may:
Thinner cylinders, commonly ranging from 5 to 25 tons and sometimes up to 100 tons, are especially prone to surface point loading.
Solutions include:
Spreading the load stabilizes the cylinder and protects the floor or ground beneath.
Failure to account for point loading can result in:
In crane applications, improper load distribution can affect lift performance and rated capacity compliance. In hydraulic systems, uneven force may create unsafe lifting conditions.
Understanding actual load forces is critical.
One solution is using a single-point load cell to measure applied force during lifting. This helps verify that no component is overloaded.
Additional best practices include:
Proper planning ensures forces remain within equipment ratings.
A common example is a sling resting on the tip of a crane hook instead of in the saddle, concentrating force on a small area.
Point loading concentrates force into a small contact area. This increases stress and can cause equipment failure or ground collapse.
Outriggers distribute crane loads across a larger surface area, reducing ground bearing pressure and improving stability.
By adding base plates, load-spreading mats, or cribbing to distribute force more evenly across the supporting surface.
LGH is North America’s largest organization devoted exclusively to lifting and moving equipment rental.
With over 90,000 pieces of hoisting, rigging, jacking, pulling, material handling, and safety equipment, LGH supports complex lifts across industries.
Need help selecting the right equipment or managing load distribution on your next lift? Contact an LGH expert today for a free quote.
