It might be the smallest tool a on heavy-lift job site, but sometimes it’s one of the most important. It’s called the triangle (also known as the load transfer triangle, handoff triangle, tri-link, or equalizer triangle).

“It’s a compact piece of rigging—roughly the footprint of a large pizza box,” said Dustin Clark, senior estimator for Central Rent-A-Crane, a member of the ALL Family of Companies. “But when two cranes must be temporarily rigged to the same bridge beam for a handoff, there’s nothing better.”

A triangle played a major role in a series of dual picks Central executed for its customer, Milestone Construction, during a recent bridge construction project in Lafayette, Indiana.

Two Central operators manning a pair of all-terrain cranes were set up on either side of a body of water. The job was to pick and set a total of five 80,000-pound steel beams. A 770-ton Liebherr LTM 1650-8.1 was position closest to the offloading zone. As a new beam was delivered via flatbed, the 1650 was rigged to the beam via the triangle. “The operator began swinging and booming with the load as the semi driver simultaneously started backing out,” said Clark.

Meanwhile, across the water, a 550-ton Liebherr LTM 1450-8.1 was waiting to accept part of the load. “Once the 1650 had gotten within the 1450’s 95-foot radius, the 1450 also connected to the triangle.” said Clark. It takes experience, concentration, and a steady hand on the part of both operators.

Both cranes are connected to the triangle only briefly. The original crane, the 770-ton Liebherr LTM 1650-8.1, then disconnected from the triangle so it could be rigged to the beam’s other end. The larger crane then picked up its end and the two cranes swung in unison to set the beam in place.

These triangle-assisted handoffs are more common in bridge work, but are still considered specialized and, therefore, critical lifts. Clark says the triangle was the most direct, affordable path to achieving the customer’s objectives.

“It’s an excellent method to temporarily share load across two cranes,” said Clark. “The riggers have all the time they need to connect and disconnect one crane without instantaneous load shifts.” The result is a smooth transfer.

Bringing in a higher-capacity AT like the 900-ton Liebherr LTM 1750-9.1 still would have required dual picking. A lattice boom crawler, more commonly used for long-term rentals of one month or more, would have required significantly more mobilization and setup time.

In this instance, both ATs were assembled on a Friday, sat in place for the weekend, and performed all five lifts the following Monday. They were disassembled and off the site by the next day.

The project demonstrated how the right rigging solution is an important component of a lift. The triangle helped make each transfer controlled and efficient, enabling the two cranes to work together seamlessly.

_{About ALL}

_{The ALL Family of Companies is the largest privately held crane rental and sales operation in North America, operating under the ALL, ALT, Central, Dawes, and Jeffers names. For a rental quote: 800-232-4100 or www.allcrane.com.}