Detailed control measures and using experienced lifting personnel (the person in control of the lift must hold at least an intermediate rigging high-risk work licence) are key success factors. This means, if the calculated maximum load share for the crane to be used is 10t, then in a two-crane lift operation, the rated capacity of the selected crane shall be at least 12t for the planned crane configuration.Ī multiple crane lift is a complicated operation, and more precautions are necessary when planning the lift. Other than a designed lift, the following minimum capacity requirements for each crane shall apply as a safety margin:įor two cranes 20% greater than the calculated share of the load.įor three cranes 33% greater than the calculated share of the load.įor four or more cranes 50% greater than the calculated share of the load. mobile cranes and tower cranes are used together for a multiple crane lift), then the lift would require a designed lift assessment. If different types of cranes are used together (i.e.
![multi crane lift multi crane lift](https://www.cumminscederberg.com/wp-content/uploads/2019/08/Dania-lift-pier-extension-1.jpg)
Lifting operations using two or more cranes at the same time shall use cranes of the same type. That’s why when performing a multiple crane lift, a documented lift plan and procedure should be prepared by a competent person, for example, an engineer, and followed. These can occur from misalignment in cranes to load, load shifting, minor errors in centre of gravity location and general crane motions. These loadings include horizontal forces acting on the boom and additional vertical load. This example uses two cranes, the same principle can be used for three or more crane lifts, but the calculation will be much more complex as the cranes are not evenly spaced either side of the centre of gravity.įor multiple crane lifts, the movement of the load between the cranes will create extra loadings on the cranes. The closer a crane is to the centre of gravity, the more load the crane will receive. size, centre of gravity (CoG), lift point position) can be used in the moment equation to calculate the load distribution (see a simple example of a load share calculation on this page). Configuration of the load to be lifted (i.e. One critical control measure is to calculate the distribution of the load among the cranes and how the load distribution will change for the entire lifting process. Lifting with multiple cranes is always more complex than lifting with just one crane, so appropriate planning, engineering and operational control measures need to be in place to manage the risks associated with multiple crane lifts. If there is a large distance between lift point locations relative to the boom length, which would impact on retaining pins, localised stress distribution and other elements of the crane.
![multi crane lift multi crane lift](https://lirp.cdn-website.com/30e548eb/dms3rep/multi/opt/Mario-Runco-E-Figli-Rende-052-640w.jpg)
If the load would be out of sight of the crane operator if it were a single crane or single crane dual hook operation. In general, these considerations may determine when you would choose a multiple crane lift (this is not a blanket fixed set of rules):
![multi crane lift multi crane lift](https://i.ytimg.com/vi/aqWpmZRgG2M/maxresdefault.jpg)
Multiple crane lifts can range from rotating a column using a lift crane at the top and a tailing crane at the bottom, to lifting a pre-assembled platform with eight cranes. Multiple crane (means a lift operation that requires two or more cranes) arrangements/methods are sometimes used on lifting jobs when physical dimensions, characteristics, mass, required movement of the load, environmental restrictions or other factors prevent the lifting operation from being performed by a single crane or single hoist. Contributed by Alice Edwards, Technical Project Engineer – The Crane Industry Council of Australia (CICA)