Specialized rigging solves complex projects

Specialized rigging is as much of an art as it is a science. Companies are using a range of equipment and ingenuity to solve complex lifting, moving and transporting projects throughout North America.

Each year in its August issue, American Cranes & Transport presents a roundup of intriguing jobs that focus on the challenges of the project and the equipment and processes required to perform them efficiently and safely.

Boring down

Tunnel boring machines (TBM) are huge, heavy and powerful machines that muscle through dirt and rock to create tunnels and passageways. PSC Crane & Rigging recently won an impressive heavy lift/heavy transport contract associated with the Dugway Storage Tunnel project in Northeastern Ohio. PSC assisted in the complicated set up and assembly of a 27-foot diameter TBM, which dressed out weighed 609 metric tons. The main component of the TBM weighed 450 metric tons.

“Our scope of work consisted of loading the over dimensional/overweight TBM components onto 20 lines of self-propelled hydraulic platform modular trailer and transporting approximately a half mile from the TBM equipment staging laydown yard to the installation shaft location,” said Randy Sever, vice president of PSC Crane & Rigging.

Once the components were transported to the installation shaft, PSC offloaded them from its SPMTs using PSC’s 700-ton capacity hydraulic J&R Engineering gantry system serving as a lift tower, in conjunction with an 800-metric ton Enerpac strand-jack system atop 80-foot girder beams spanning a 50-foot diameter by 200-foot deep shaft.

As the components were lowered into position for assembly, PSC’s team jacked and slid them laterally into the starter tunnel approximately 300 feet utilizing a 1,000-ton capacity Hydra-Slide Up & Go skidding system.

The project required a highly engineered plan and a host of very specialized equipment. Sever said the plan was executed flawlessly.

Among the challenges, the installation shaft was 50 feet in diameter and had a depth of 200 feet below the ground surface. PSC was required to provide onsite loading and transport of 12 main components from the staging laydown yard to the installation shaft location and then lower six of the 12 main components into final position for assembly.

Bridge jack up

The historic San Francisco-Oakland Bay Bridge was an incredible engineering feat spanning more than eight miles across the Bay. Safely taking down such a monumental structure containing 152,000 tons of structural steel is a huge task. Burkhalter Rigging removed the trusses using the Enerpac jack-up system.

A custom-developed multi-point lifting system, Enerpac’s typical system includes four jack-up towers positioned under each corner of a load. The four-tower setup has a lifting capacity of 2,000 metric tons, or 500 metric tons per tower.

The lifting frame of each jack-up tower contains four hydraulic cylinders, one in each corner, which lift and stack steel boxes. A load is lifted in increments as boxes are inserted via an automated system – lifted and stacked, forming the lifting towers.

“In preparing for the Bay Bridge demolition, Burkhalter asked us if the equipment could be used at 36 meters in height,” said Mike Beres, Americas sales leader for Integrated Solutions at Enerpac. “After determining the system could safely operate at this height, Enerpac was awarded a contract to supply boxes that will enable the jack-up system to nearly double its height, rising to 36 meters and making it the world’s tallest jack-up system.”

Increasing the system height involved adding 56 boxes and four special boxes designed for this job to ensure stability at that height. Burkhalter added securing wires and bracing to improve structural stability and to tie into the four strengthened corner-bracing units. Combined, these features accommodated the extra 14 boxes per corner.

The computer-controlled jack-up system is safe and easy to use, Beres said. Each tower’s lifting and lowering operations occur simultaneously, and the computer control unit’s synchronous technology maintains the load balance for safety, accuracy and efficiency.

Fourteen 288-foot trusses, weighing 1.7 million pounds and stretching approximately three quarters of a mile, were the first of the smaller trusses to be demolished. This lowering process was more complicated and extensive than the process of lowering the five 504-foot trusses that were dismantled earlier.

The challenges included varied marine foundations and water depths and generally cool, damp weather. The demolition was a highly weather-dependent, two-day operation, requiring 12 to 14 hours of work. Heavy rains and/or high winds would have disrupted the scheduled demolition plan and operations.

Burkhalter set up the Enerpac Jack-up System on a barge, and floated it under the truss section slated for removal. The system was carefully raised to a point just below the truss, before being raised to take the load. The truss was then cut, separated, lifted up and floated off the foundation. Once clear of the foundation, the truss was brought down to a lower elevation and then delivered to the Port of Oakland.

“Working with the Enerpac team, we developed the concept of a taller jack-up system that retained the 2,000 metric ton lift capacity and versatility of multipoint synchronized lifting,” said Burkhalter Project Manager David James. “The barge-mounted Enerpac jack-up system was a more efficient way to lift the bridge off its foundations, compared to the strand jacks we considered using for this project.”

Engineers used a 3-D finite element computer program model to determine the safest and best way to remove high-tension pieces. The model showed how the forces were distributed based on structural analysis and historical records. For the demolition, 90 retroreflector prism targets were installed at key locations to monitor the span. As bridge members were removed, updated target locations were determined entered into the computer model and compared to the predicted locations in the software model.

Press excellence

Lee Contracting is an industrial contractor that self-performs electrical, rigging, mechanical, foundations, machine repair and fabrication. When all of its trades work together they complement each other, and seamlessly execute the complicated projects for Lee’s customers, the company said.

Lee’s team recently installed two 2,500-ton Fagor presses using the company’s 500-ton capacity Lift Systems Power Tower. The company’s foundation team started with demolishing part of an existing exit scrap conveyor tunnel so they could extend the press pit for the new presses. The newly installed pit was 38 by 36 feet and 20 feet deep. With the addition of these two new presses the scrap conveyor was extended another 20 feet and included a bump out for the aluminum bailer.

While working in an active manufacturing facility, Lee’s riggers worked to fully assemble each of the presses internal components. They were shipped in 16 separate crates to the United States from Spain. When fully assembled, the base of the press weighed 150 metric tons, the slide weighed 112 metric tons and the crown weighed 225 metric tons. The flywheel alone weighed 15 metric tons, while the two eccentric gears weighed 30 metric tons each. The riggers then used Lee’s 500-ton capacity 34PT5400WT dual power gantry system to stack each of the presses and install a feedline for the presses.

Lee’s electricians and pipefitters worked on all of the electrical, hydraulic and piping interconnections to the press. This included setting a new primary transformer, installing a new 2,000-amp switch gear, installing a 1,200-amp main power feed to the new presses, installing chiller water, compressed air, a fire suppression system and an oil containment trench drain.

Lift, slide, repeat

Fagioli used its 500-ton capacity Hydra-Slide HT500 heavy track hydraulic skidding system and other rigging equipment to remove a 230,000-pound pipe bending machine and replace it with a spare system.

Fagioli’s scope of work included removing the existing machine from a pit, slide it to a loading area, loading it onto a hydraulic trailer and repeating the operation in reverse with another pipe bender that was kept in storage for replacement purposes. Both systems were identical in weight and measured 18 by 10 by 8 feet.

Cowboy’s Services Inc. (CSI) hauled the machines and sub-contracted Fagioli to execute the replacement operation. The job required three days of planning and three days of installation.

“We already had plans to acquire a Hydra-Slide skidding system and securing the order from CSI was the tipping point to proceeding with the purchase,” said Edoardo Ascione, president and managing director of Fagioli Inc.’s U.S. division.

The team also used four 200-ton capacity Fagioli hydraulic climbing jacks and timbers to raise the machine 6 feet out of the pit before commencing the slide some 60 feet.

Ascione explained that due to limited headroom, the combination of climbing jacks and skidding equipment was the only viable solution to replace the machine. The HT500 has a total height of only 8 inches, saving jacking time and suiting the product to such confined spaces.

“The design information for the machines was not complete, as is often the case for such equipment,” said Ascione. “We estimated the center of gravity based on how the machine was supported in the pit. The capacity of the jacking system was a lot more than required, as a measure of safety. Once the jacks took the load we could confirm the position of the center of gravity and carry on the replacement operation.”

A leg up

Last year Mammoet Italy reached out to the Mammoet USA team to help a client on a tight deadline. The scope of work was to modify a deck for an offshore platform in New Iberia, LA.

The deck and jacket were scheduled to be transported to the Congo in West Africa. To meet the environmental specifications, the legs needed to be shortened by 24.5 feet. With a timeline in place, the operation needed to be quick, within budget and pose as little risk of damage to the deck and jacket as possible. The clock was ticking.

The deck was 89 feet wide, 83 feet tall, 95 feet long and weighed 880,000 pounds. The original approach was to use a climbing jack and block method. This method would gradually lift the deck so that a small section of the legs could be cut and then the deck would be lowered. The process would be repeated five times before the legs were cut at the desired points.

But this plan was time consuming and the longer the deck was elevated increased the possibility of wind-related issues, stability issues, damage to the deck and injury to personnel working below. Mammoet believed this could be done quicker, simpler and safer using a JS500 jack-up system. With the right planning, engineering and modifications to existing equipment, Mammoet could lift the entire deck with the JS500 system and cut the legs at the correct points at one time. This solution would be faster and reduce the potential risks associated with the deck being elevated for an extended period. It was also more cost efficient.

For this solution to work, Mammoet’s engineering team would have to work through a couple of challenges. While the ground conditions were good, the job site was susceptible to high winds. Engineering would have to ensure that the deck would be stable in winds up to 30 miles per hour.

The second challenge was that the JS500 has a maximum reach of 33 feet, and to reach the required height to cut the legs, modifications would need to be made to exceed the system’s limits. Mammoet would have to find a way to add another 18 feet to support the deck. After hours of meticulous pre-planning regarding engineering, safety and technical capabilities, Mammoet came up with a solution and was ready to execute.

Mammoet asked the client to add temporary bracing to the deck. The additional bracing would create new, strong jacking points to keep the deck stable during the cutting and removal of the legs. To save the client time and additional costs, Mammoet suggested a minimal amount of necessary bracing be added. The deck would need to be supported at 35 feet on one side and 51 feet on the other.

After the bracing was added, the JS500 was assembled. To exceed the 33-foot lifting capacity of the system, Mammoet made modifications to some of its existing auxiliary equipment. On the shorter side, a steel mat was secured to the first two JS500 cans placed into the system.

On the other side, four steel jack stands were secured together, secured on top of a steel mat and then to the top of the first two cans in the system. The JS500 cans were fed into the system one by one until the mats and modified jack stands met the jacking points.

Once in place, Mammoet added two additional braces for extra wind protection. The legs were ready to cut.

Once the lower section of the legs were detached, Mammoet raised the deck as far as the modified system could reach to allow clearance for the 24.5-foot, 40,000 pound sections to be removed. Because of limited space, each leg had to be removed with only four axle-lines of SPMTs.

Mammoet executed the jacking process in three hours. Once all four legs were cleared from the area, the deck was lowered, seated into cup cans and welded out. Mammoet held the load with the JS500 until the welding was complete.

Tanked up

Vigor Industrial subcontracted Oxbo Mega Transport Solutions to provide equipment that could lift and precisely set four 1,100-ton tanks that measured 95 feet long by 76 feet wide and 54 feet tall and four 600-ton decks that measured 100 feet long by 94 feet wide by 32 feet tall for a new barge construction project.

One of the major challenges of the project was that the tanks had to be lifted 60 feet in the air to clear the existing barge walls and then moved 300 feet over the top of the barge to be in position to lower 60 feet down into the hull. Once the tanks were in place, the 600-ton decks needed to be lifted 70 feet in the air and then slid over the top of tanks and set into place.

The team at Oxbo designed, engineered, fabricated and erected a 1,200-ton capacity gantry system that was mounted on the company’s skid system. The lifting system was a set of four 600-metric ton strand jacks that were driven by four diesel power packs located on the top of the gantry. All the controls were routed to a control center that was mounted on the lower leg of the gantry. With the four strand jacks, the hydraulic lift cylinders on the skid system and the ability to skid the entire gantry gave Oxbo precise control of three different directions of movement from one central command center. Each of the eight picks were able to be safely and efficiently completed in a single 10-hour shift from start to finish.

Tight headroom

Burkhalter set a 160,000-pound galvalume pot in the basement of a working operating facility using gantries. To save the customer time, Burkhalter set up the gantries and equipment on the top floor while the plant was still operational and, once the shutdown occurred, utilized gantries with counterweights cantilevered behind them to hold the pot out in front and set it into the basement, with mere inches of clearance.

The job spanned 10 days. Burkhalter developed a plan that involved the use of a 500-ton capacity J&R Engineering Lift N Lock gantry.

The focus of the project was the headroom, which was about six inches. And for the circle in which the pot would be lowered into the basement there was less than one inch of clearance.

Burkhalter developed a rigging plan to work within the tight quarters. It was critical that the string length was exact to have strength but didn’t hit overhead structures.

The pot was assembled in an adjacent bay. The weight of the pot, with the lifting equipment and counterweights, was greater than the acceptable load bearing of the concrete floors.

The gantry system was constructed using an existing 20-ton overhead crane. Climbing jacks were used to shore up the floor to protect the structure. The work was performed during a shutdown and happened over three-day period. It took a day to setup up the equipment and to shore up the floor. Then there was a day to set the pot and then a day to break everything down.

Many of the keys to success of this project was the safety plan. Workers always wore PPEs. Another key to the success of this job was the innovation of using a gantry system to create a cantilever system to lower the pot.

Burkhalter used counterweights from its Liebherr LR1400 from its nearby Columbus, MS yard. The innovative use of equipment provided a safe and efficient solution to save time and money for the client.

Engine lifter

Shuttlelift recently delivered a 100,000-pound SB50 rubber-tired gantry crane to Mustang Cat Power Systems in Houston, TX. Mustang Cat is the authorized Caterpillar dealer in Southeast Texas offering earthmoving equipment, power systems, vocational trucks and more. The Houston location serves as the headquarters to the greater metro area and specializes in handling large 3,500-3,600 Cat industrial engines.

“We handle a very high volume of these engines on a day-to-day basis,” said Scott Weaver, service operations manager. “Our new Shuttlelift allows us to stack them in rows much more efficiently. Rather than spending an hour on a forklift to get the next engine in line, our SB50 allows us to essentially walk the machine down the rows and bring them directly to the front with a single pick, saving a tremendous amount of time.”

The flexibility of the Shuttlelift gantry crane has continued to streamline operations through the latest features designed to meet their exact specifications.

“The versatility we now have throughout our day-to-day operations is what gave Shuttlelift the competitive advantage,” said Weaver. “With the wireless remote control, we have the capability to turn what used to be a two or three-man operation into a one or two man job with just one spotter walking around, improving our maneuverability and operational safety.”

In addition to being equipped with the wireless remote control package, Shuttlelift’s engineering team designed the 100,000-pound capacity machine with a custom spreader capable of handling their complete line of industrial engines. The LED light package also provides the ability to keep operations running through the night.n