Terex AC 350/6 expands the range of jobs at Landwehr Construction
“The crane made us money,” says Chuck Paulson, crane manager for 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 based in Minnisota, USA made the bold move to invest in the 350t (400USt) crane capacity class and bought the Terex AC 350/6 all terrain crane. Since then the crane has not often seen Landwehr’s yard.
Prior to the purchase, the fifth generation family company had a crane fleet ranging from 30 to 275USt capacity, however, increasing competition and changes in the market necessitated an increase in crane capacity.
Pat Herron, crane division manager for Landwehr says, “Simply put, we were missing out on the next level of work, the jobs with longer reaches and heavier lifts. 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 400USt class, there is less competition, especially when heading west toward the Dakotas, and we have a customer base where we will travel up to 500miles [805km] for a lift project.”
Landwehr’s heritage stems from the construction industry and 250t (275USt) class cranes did not offer enough capacity for the growing body of construction work, but another reason for purchasing the AC 350/6 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 39,900lb [18,1t] counterweight package and one supporting truckload, and for 275USt [250t] capacity class jobs we use 76,500lb [34.7t) 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 64m (210ft) main boom, and multiple luffing jib options give Landwehr a maximum 125.7m (412.4ft) 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 win and profitably complete two recent back-to-back industrial lifts.
Landwehr mobilised its AC 350/6 all terrain crane 72.4km (45miles) from its headquarters to Melrose, Minnesota for a cooling tower lifting project at a dairy processing facility. Due to the tower’s weight, the facility’s wall height, and how deep into the roof supporting materials had to be placed, the pick required 48m (157.5ft) of luffing jib. “The crane can be equipped with up to 72m (236.2ft) of luffing jib to increase machine flexibility,” says Ben Steege of RTL Equipment, the supporting Terex authorised distributor.
The crane’s full 116.7t (257,300lb) counterweight package was required to lift the 13.6t (30,000lb) cooling tower. Mobilising 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 maximise truckloads, which helps us to keep trucking costs down to remain price competitive.” Within 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 13.6t cooling tower critical pick. “Lift planning for the cooling tower,” says Paulson, “was one of the biggest challenges. We had to devise a flight plan to minimise worker evacuation for the cooling tower pick, since this was an active factory during work hours.” To clear the 7.6m (25ft) tall factory wall while lifting the 3.7m wide by 7.3m long by 3m high (12 x 24 x 10ft) cooling unit, the crane’s centre pin was positioned 7.9m (26ft) away from the building.
Crews initially used 22.7m (74ft) of main boom with the 48m (157.5ft) of luffing jib positioned at 73deg. “At this configuration, the AC 350/6 crane offers a 16.4t (36,200lb) capacity at a 46m (150.9ft) radius,” says Steege. Some of the structural steel had to be placed an additional 24.4m (80ft) into the building’s roof. For this, the crane operator telescoped the main boom to 54.3m (178ft) and changed the luffing jib’s angle to 65deg.
“This gave us a 2.7t (6000lb) capacity when we were working at a 70.1m (230ft) 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 72.4km (45miles) trek to Little Falls, Minnesota to lift and remove a 27.2t (60,000lb) vessel at an ethanol plant. This time, Landwehr called upon the crane’s Superlift structure to boost main boom lift capacities. Using 95.7t (211,000lb) of counterweight, the operator needed 177.8ft (54.2m) of main boom to lift the 34.4m (113ft) tall vessel. It worked at a 21.9m (72ft) radius to manoeuvre the vessel into its final position.
“The Superlift boosts the crane’s capacity to 34.8t (76,700lb), 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 16.7m (54.8ft) 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 manoeuvre the carrier into tight spots,” says Steege.
Paulson adds, “The ability to boom up and work in as little as a 26.2ft [8m] 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 can successfully use the AC 350/6 all-terrain crane.