Our LTM 1300 (350-ton Crane) and ATF 220 (250-ton Crane) working together is a sight to see! Though a tandem lift can be a complex, tricky, even dangerous operation, professional planning, experienced supervision, and precise execution turn projects into moving works of art.
When is a 2-crane, tandem lift necessary?
Simply put, a tandem lift is needed when objects are too large or too heavy to lift with even a powerful 500-ton crane. Most often, projects that require tandem lifts are placing heavy structural beams for bridges, shifting long components from horizontal to vertical positions, or moving objects near power lines. Also, small sites or locations that have loose soil conditions might not be accessible or stable enough to use a large single crane. In these situations, two smaller cranes that sit apart from each other are more stable and can lift the desired loads.
Why choose Consolidated Crane & Rigging for a complicated lift?
The lift must also be directed by a experience, qualified professional who understands all aspects of the project like load distribution, lift sequence, and crane position. Then, we review complete plans in a meeting with all workers who will be involved in the operation to for identify all potential hazards and address them.
Beyond thorough planning, excellent and reliable equipment is needed to execute a tandem lift.
Our Cranes.
Our Crew.
Our Equipment.
More on Tandem Lifts
Project Safety… Always
The goal of any and all jobs is to ensure the lift can be completed safely. For the lift to be safe, the cranes must not be overloaded or side loaded. When a lift involves more than one crane, there are many factors that could cause an overload situation to arise, and they must be accounted for when a plan is developed.
Center of Gravity
It is necessary to know the center of gravity of a load to be able to balance the load correctly and distribute the load between cranes as desired. Provisions must be made for any condition that could cause a shift in the center of gravity, such as strong winds or fluids in or on the load. If the center of gravity shifts during the lift, the crane nearest the center of gravity could become overloaded. Otherwise, It is easy to lift, jack, and transport an object whose center of gravity is right in the middle. Tandem lifting becomes more complicated when loads comprise many individual objects with a center of gravity not in the middle. Skids containing products from various suppliers, oilers with pressure vessels located in specific spots, or vessels with varying diameters require personnel to carefully calculate the center of gravity before executing a tandem lift.
Crane Capacities
There are two options for managing load in a tandem lift, “equal distribution” or “unequal distribution.” When the load is distributed equally between both cranes, it can be beneficial to use cranes of the same model or the same capacity range. Using two of the same or similar cranes will make it easier to synchronize movements between them, which will help reduce the chance of overloading. If the load is not distributed equally, cranes of different capacities can be used based on the portion of the load that will be carried by each crane. If the cranes have different movement speeds, our lift plan will define how to keep the cranes synchronized to keep the center of gravity.
Rigging the Loads
Like the cranes, all rigging and lift equipment must have the necessary lifting capacities. And tandem lifts often require the use of additional rigging and lift equipment like equalizer beams to manage load distribution by keeping the load distributed evenly in case crane movements become unsynchronized. Additional rigging equipment can also be used to ensure the load is lifted above the center of gravity, rather than below it, for the most stability. Lift equipment can also add significant weight to the load, so our plans will account for the additional weight of any equipment plus the weight of the load itself.
Communication is Paramount
A tandem lift will have a precisely defined system of communication to avoid any unintended movements. Our professional directing the lift instruct the machine operators and relay persons may be used between the supervisor and operator. Both operators and relay positions are very familiar with all commands and communications.