Terex AC 350/6 crane at work .
“The crane made us money,” says Chuck Paulson, Crane Manager for St. Cloud, Minn. -based Landwehr Construction, Inc., after completing back-to-back cooling tower installation and petro vessel removal projects for customers. “Had we not had a machine like the AC 350/6 crane, we could not have competitively bid the jobs.”
A little more than six months ago, Landwehr made the bold move and jumped up to the 400-US-ton (350-tonne) crane capacity class by investing in the Terex AC 350/6 all terrain crane. Since that time, the crane has not often seen Landwehr's yard. Prior to the purchase, the fifth generation family company that traces its heritage to the turn of the 20th century had a crane fleet ranging from 30 to 275 US ton (27 to 250 tonne) capacity class. However, increasing competition and changes in the market necessitated the increase in crane capacity.
“Simply put, we were missing out on the next level of work, the jobs with longer reaches and heavier lifts,” says Pat Herron, Crane Division Manager for Landwehr. “We were a little hesitant to make the jump at first, but, with our headquarters within about an hour's drive of Minneapolis, there is much competition in the lower capacity classes. Once you get to the 400-US-ton (350-tonne) class, there is less competition, especially when heading west toward the Dakotas, and we have a customer base where we will travel up to 500 mi (805 km) for a lift project.”
Landwehr's heritage stems from the construction industry. The company completes a broad range of work, ranging from utility and excavation and site development to environmental remediation and solar services. For decades, the crane and rigging division's primary work stemmed from lifts to support the other Landwehr divisions. The 275-US-ton (250-tonne) class cranes did not offer enough capacity for the growing body of construction work.
“Precast tilt-up walls for commercial building construction projects were getting bigger and heavier, and the radius and panel size were increasing,” comments Paulson. “We recently finished a department store construction project where the wall panels were 120,000 lb (54,4 t). If our fleet topped off at the 275 US ton (250 tonne) class, we would lose out on that work.”
Versatility and Durability
The type of 400-US-ton (350-tonne) capacity crane to add to Landwehr's fleet was made easier from previous experience of another all terrain crane. Sixteen years ago, when Paulson joined the Landwehr team, the company had just five cranes in its fleet. In 2016, that number has increased to 23 cranes, as the contractor has added taxi service and crane rental to its list of crane and rigging services provided.
“We have quite a few Terex cranes, including 30- and 60-US-ton (27- to 54-tonne) rough terrain cranes and other all terrain cranes,” says Herron. The longevity delivered by Landwehr's 2005 model Terex® AC 140 all terrain crane helped to tip the scales in favor of purchasing the larger AC 350/6 crane. “That AC 140 crane has more than 167,770 mi (270,000 km) on it, and it is still hammering down the road from site to site,” he continues. “We've only had to put one set of tires on it, and we have not had to put a lot of maintenance in it.”
Another reason for the AC 350/6 purchase is versatility. Using different counterweight configurations, Paulson reports that the crane is used on multiple jobs, and, depending on how much counterweight is needed to complete a lift, he can send just one, but no more than six, additional supporting truckloads for the full counterweight package.
“While we always want jobs with maximum counterweight, the ability to adjust counterweight packages keeps this crane busy,” explains Paulson. “We will go out with a basic 39,900-lb (18,1-tonne) counterweight package and one supporting truckload, and for 275-US-ton (250-tonne) capacity class jobs we use 76,500 lb (34,7 tonne) of counterweight. The ability to vary our counterweight keeps trucking costs down, so we remain competitive.”
Multiple boom options for the all terrain crane increase the project adaptability for Landwehr as well. The AC 350/6 crane offers a maximum 210 ft (64 m) main boom, and multiple luffing jib options give Landwehr a maximum 412.4 ft (125,7 m) system length for lifting flexibility at the project site. Additionally, the crane's Superlift structure for the main boom increases lift capacities when working at extended radius.
The combination of long luffing jib and Superlift configurations helped Landwehr to land and profitably complete two recent back-to-back industrial lifts.
From Dairy to Diesel
Landwehr recently mobilized its AC 350/6 all terrain crane 45 mi (72,4 km) from its headquarters to Melrose, Minn. for a cooling tower lifting project at a dairy processing facility. Due to the tower's weight, facility's wall height and how deep into the roof supporting materials had to be placed, the pick required 157.5 ft (48 m) of luffing jib. “The crane can be equipped with up to 236.2 ft (72 m) of luffing jib to increase machine flexibility,” mentions Ben Steege of RTL Equipment, the supporting Terex authorized distributor.
The crane's full 257,300-lb (116,7-tonne) counterweight package was required to lift the 30,000-lb (13,6-t) cooling tower. Mobilizing the crane, luffing jib and counterweight required a total of only seven truckloads. “The base crane goes out with one basic counterweight and rigging truckload,” says Paulson. “Full counterweight requires an additional five trucks, and we need one additional truck for the luffing jib. The way the counterweight slabs and jib segments are designed helps us to maximize truckloads, which helps us to keep trucking costs down to remain price competitive.”
Within about an hour, the crane and truckloads arrived at the dairy facility. It took Landwehr's four-person rigging crew plus two operators just five hours to configure the AC 350/6 crane with maximum counterweight and luffing jib for the lift.
Including the tower unit, supporting structure pieces, catwalks and ladder, the crane made a total of 12 picks for the job. By far, the most complex part of the lift was the 30,000-lb (13,6-t) cooling tower critical pick. “Lift planning for the cooling tower,” recalls Paulson, “was one of the biggest challenges. We had to devise a flight plan to minimize worker evacuation for the cooling tower pick, since this was an active factory during work hours.”
To clear the 25-ft-tall (7,6-m) factory wall while lifting the 12-ft-wide by 24-ft-long by 10-ft-high (3,7- x 7,3- x 3,0-m) cooling unit, the crane's center pin was positioned 26 ft (7,9 m) away from the building. Crews initially used 74 ft (22,7 m) of main boom with the 157.5 ft (48 m) of luffing jib positioned at 73 degrees. “At this configuration, the AC 350/6 crane offers a 36,200-lb (16,4-tonne) capacity at a 150.9 -ft (46-m) radius,” says Steege.
Some of the structural steel had to be placed an additional 80 ft (24,4 m) into the building's roof. For this, the crane operator telescoped the main boom to 178 ft (54,3 m) and changed the luffing jib's angle to 65 degrees. “This gave us a 6,000-lb (2,7-tonne) capacity when we were working at a 230-ft (70,1-m) radius,” says Paulson. “The ability to change main boom length during the lift was the key to economically using this crane and winning the bid.”
Within eight hours, all the lifts were made. Afterwards, Landwehr's crew had the crane derigged in about five hours and prepped to move for its next project. It made another 45-mi (72,4-km) trek to Little Falls, Minn. to lift and remove a 60,000-lb ((27,2-tonne) vessel at an ethanol plant.
This time, Landwehr called upon the crane's Superlift structure to boost main boom lift capacities. Using 211,000 lb (95,7-tonne) of counterweight, the operator needed 177.8 ft (54,2-m) of main boom to lift the 113-ft-tall (34,4-m) vessel. It worked at a 72-ft (21,9-m) radius to maneuver the vessel into its final position. “The Superlift boosts the crane's capacity to 76,700 lb (34,8 tonnes), which was more than enough to make this lift,” says Paulson.
With space being tight at the refinery, the all terrain crane's size and close radius working capabilities proved to be significant benefits for Landwehr. “At a mere 54.8 -ft (16,7-m) total length, the AC 350/6 is the most compact six-axle crane in its capacity class, and it offers six different steering modes to easily maneuver the carrier into tight spots,” comments Steege.
Paulson adds, “The ability to boom up and work in as little as a 26.2 -ft (8-m) radius in this configuration made removal of the vessel in tight quarters go smoothly. By being able to quickly change from the luffing jib configuration to main boom with SL configuration, we were able to use the same crane to win bids for two different applications against multiple crane companies.”
The crane's ability to adapt to a variety of lift configurations has Landwehr expanding the types of applications where it considers successfully using the quick, nimble and powerful crane. While a true economic benefit for Landwehr, it serves to extend the times the crane is required in the field, making the AC 350/6 crane increasingly homesick for Landwehr's yard.
For more about Landwehr Construction, Inc., follow this link: www.landwehrconstruction.com/
For more information about Terex, visit www.Terex.com.