Compactness, capacity, and reach are enabling a Maeda MC305-2 mini-crane to play a major rooftop role in getting a high-rise construction project back on track in New York City after Hurricane Sandy. JV Trucking & Rigging LLC, Manalapan, N.J., has perched the Maeda mini-crane atop a 1,020-ft tall high-rise luxury condominium building that’s going up in Manhattan. The 75-story building is reportedly the tallest residential building in the city, as well as the city’s tallest building that uses only concrete for its structural members.
JV Trucking & Rigging is a full-service rigging, transportation, and warehousing company that serves New York City and the surrounding area. Its range of services includes rigging for heavy lifts, machinery moving, mechanical and HVAC rigging, demolition, and consulting. It also offers crane service to 600 tons and a certified tower crane division. Vice president Joe Volpe is a licensed master rigger certified to work in New York City, and the company’s staff includes crane operators and rigging foremen who are certified and licensed. At the high-rise project in Manhattan, JVT&R is working for the project’s general contractor, Lend Lease Corp.
JVT&R is currently removing and replacing a tower crane that was damaged when a 150-mph burst of wind from Sandy raced up the side of the building, folded the crane’s lattice boom backward over its machinery house, and left a several story-long section of boom dangling over the street nearly 1/5 mile below.
Compact crane ideal
JVT&R needed a way to remove previously installed structural steel framing above the roof, handle sections of the damaged tower crane boom as they were removed, and assemble a rooftop derrick that would lower the damaged tower crane’s rotating platform to the ground and lift its replacement to the top of the tower.
Joe Volpe, vice president, said: “We had two ways we could do this job. One was using a large helicopter; the other was a mini-crane. The mini-crane was the far better choice from every angle—safety, simplicity, efficiency, and cost.”
Using the internet, JVT&R searched for a mini-crane that had the required reach and lifting capacity plus the compact dimensions to fit the rooftop space. The crane also had to be easy to disassemble so that the project’s construction elevator could carry it to the rooftop, and it had to be certified to work in New York City.
JVT&R’s search yielded one crane that fit all its requirements: the Maeda MC305-2, which was available for rent from Maeda’s regional dealer, Key Equipment Sales & Rental, Inc., Honeybrook, Pa. “We’ve used mini-cranes before, particularly in taking down the Deutsche Bank building at Ground Zero after the 9/11 attacks,” said Volpe. “But the Maeda MC305 was the only one that had the vertical reach and capacity to handle the loads on this job.”
JVT&R’s plan called for the project’s construction elevator to carry the MC305 up 75 stories to the rooftop. Although the minicrane’s 14'1" length, 4'3" width, and 5'7" height would fit easily into the elevator, its 9,100-lb.weight was heavier than the elevator’s 7,000-lb. capacity. That meant that some of the crane’s components would have to be removed for the elevator ride, then reassembled when the crane was on the building’s roof. “Key Equipment was really helpful,” said Volpe. “The elevating and reassembly went quickly and smoothly.”
Key Equipment President Brian Funk said that in order to get the weight of the Maeda mini-crane’s main body down to 6,800 lbs. for the elevator ride, Key Equipment crews took off the crane’s load block, removed all four outriggers, and also drained all of the hydraulic fluid and diesel fuel at the company’s northern New Jersey warehouse before delivering the crane to JVT&R’s jobsite in Manhattan.
“We wanted to deliver it elevator-ready to save our customer time and money,” said Funk, who also notes that the Maeda MC305 and the smaller Maeda MC285 are both approved by the New York City Dept. of Buildings, so getting permits to use them in the city is easy.
According to Tony Inman, president of Maeda USA, Houston, Texas, disassembly is common for mini-cranes. “Even in places as remote as oil and gas sites in the Amazon, Maeda mini-cranes are frequently disassembled and flown in by helicopter, then reassembled in the middle of the jungle. It’s just part of what they are designed for,” he said.
In addition to easy disassembly and reassembly, many of the MC305’s features have been helpful on this job. On the tight rooftop site, the option of setting the outriggers at the 15'10" full spread, 14'6" intermediate spread, or 13'2" minimum spread has allowed the crane to work in whatever space is available. In one case, space was so tight that one of the outriggers was placed atop the building’s perimeter wall.
The boom’s 360° continuous swing simplifies load handling and offers more options for crane placement, while the load-moment limiter, tilt alarm, and anti-two-block systems provide an excellent safety system.
Safety is paramount to JVT&R. “We do every job with an eye on safety, and it’s a pleasure to work with other professionals who hold the same view. On this project, everyone involved—from the city, to the owner, general contractor, us and the ironworkers—puts safety first,” said Volpe.
Many kinds of work
JVT&R has used the Maeda mini-crane steadily since perching it atop the building. Its first job was to handle steel beams from a rooftop structure that had to be dismantled to make room for the mini-crane and the derrick crane to work.
It then handled 5-ft. lengths of the tower crane’s damaged lattice boom as ironworkers from Piermount Iron Works, Wayne, N.J., cut them up. Volpe said that for the safety of people on the street below, the process involved putting a “cocoon” safety net below the boom section, connecting the Maeda’s load line to the piece being worked on, and then cutting the piece off with saws instead of torches, so no sparks would fall. To reach the sections of damaged boom, the ironworkers used telescopic boom lifts parked on the roof and in the building.
The Maeda then lifted or lowered each cut-off section to a landing on the 72nd floor, where it was pulled into the building and then taken to the ground on the construction elevator. The Maeda mini-crane also helped remove other parts of the tower crane, including boom stops, boom-support bridles, and sheave assemblies.
Most recently, JVT&R used the Maeda MC305 to assemble a 40-ton Timberland derrick with 94 ft. of boom on the building’s roof. The derrick will lower the rest of the damaged tower crane’s machinery deck to the ground, and then lift a replacement crane to the top of the tower, which was unaffected by the hurricane.
Components for the derrick’s sills, masts, swing-bearing support, boom, machinery deck, and counterweights were carried to the roof by the construction elevator. The Maeda then handled all of them for the crane-erection crew.
Its most challenging lift was placing the derrick’s mast top. “The mast top with sheaves weighs 1,650 lbs. and has to be installed at a height of 38'6",” said Volpe. “The Maeda mini-crane has a capacity of 1,740 lbs. at its maximum lifting height of 41 ft., so we needed every bit of its capability for that lift.”
As the project continues, the Maeda will stay on the roof to help handle materials and to be on standby for the derrick.
“Having the right equipment makes a big difference in how efficiently a project flows. The mini-crane was perfect for this job. We couldn’t have done it without that crane,” said Volpe.
Lift & Access is part of the Catalyst Communications Network publication family.
