The design of the latest generation of crawler cranes is being clearly defined by customer requests and site requirements. Laura Hatton reports
Crawler cranes are an ideal choice for longer term construction site projects, including power plant construction, wind farms, infrastructure and bridge work. “A crawler crane can also be installed on a special platform on a barge for use at sea” John Kennedy, Manitowoc’s senior vice president of crawler cranes, adds. “Such barge cranes perform material handling, installation and general construction work.”
Other factors that make crawler cranes an ideal choice are the ability to travel with a load, higher lift capacity compared to other crane types and the ability to be fitted with ring and tower attachments. The latest crawler crane model with these design features in mind from Lampson International is the Lampson Millennium 4100. The crawler has a computerised control system, hydraulic hoists and increased line pull. In addition, it is capable of handling tandem drum operations and can be configured with Manitowoc ringer and tower attachments without modification. Power comes from Tier 3 and Tier 4i Cummins engines.
Kate Lampson, Lampson International says, “Knowing that safety is paramount in the construction industry, we added no free fall capabilities to our crane. Not only does this feature allow the operator to lock the load, it also allows what was once viewed as an unsafe friction rig to work on almost any of today’s jobsites.”
New in 2014 from Manitowoc are the 300 tonne capacity MLC300 and 650 tonne MLC650 crawler cranes. The MLC300 has a 96 metre boom and the option of a fixed jib attachment; a 96 m luffing jib can be added to extend its reach to 144 m. The MLC650 has a 104 m main boom to which a fixed jib can be added. Both models are fitted with the Manitowoc Variable Position Counterweight (VPC) system, which automatically positions the counterweight to fit the required lift.
“The counterweight moves along the rotating bed and is automatically positioned based on changes in boom angle,” John Kennedy explains, “Advantages for customers include reduced ground preparation, lower ground-bearing pressure and less counterweight, without sacrificing capacity.”
For barge work there is also the VPC-MAX attachment, which allows increased capacity. Kennedy explains, “Because the counterweight attachment of the VPC-MAX on the MLC300 and the MLC650 never touches the ground, higher capacity lifts on barges that customers were never able to perform before are now possible.”
The latest crawler from Terex is the CC 8800-1 with Boom Booster kit. The kit is designed for steep and long boom configurations. It increases the CC 8800-1 capacity by up to 90 % and offers up to 72 m of boom structure. It can be disassembled and shipped in standard 12.2 m open-top containers. With safety in mind, Terex developed the Terex Cranes Fall Protection System, which is available for the Boom Booster as well as the Superlift 3800. For more on the Terex boom booster see IC April 2014.
The latest models from Chinese crane manufacturer Zoomlion are the ZCC550, which has a 55 tonne capacity and a 52 metre boom, and the ZCC800, which has an 80 tonne capacity and 58 m boom. Also from Zoomlion are several other models, ranging from the 130 tonne capacity QUY130 to the 650 tonne capacity QUY650.
The latest product series from Chinese manufacturer Sany includes the 8 series (developed with a China-USA associated research and development team), the E series and the A series. From the 8 series is the SCC8100-2, an updated version of the SCC8100 which is to be marketed in 2015 with a Euro 4 emission regulations engine. Also new is the SCC4000A, an upgraded version of Sany’s SCC4000. New E series products will include crawlers of less than 200 tonnes. The models have transport widths of 3 metres and a maximum component weight for transport of 50 tonnes, the manufacturer said. They are designed to meet CE certification requirements. At the top end of the capacity scale Sany offers the 1,000 tonne capacity SCC10000, the 1,600 tonne SCC16000 and the 3,600 tonne SCC36000.
The latest crawler crane from Liebherr-Werk Ehingen is the 1,000 tonne LR 11000. First presented in 2013 the LR 11000 has a 1,000 tonne capacity. An option is the Power Boom capacity enhancement system with a heavy luffing jib. It operates with a maximum of 250 tonne slewing platform ballast, 90 tonne central ballast and up to 450 tonne derrick ballast, which is fully adjustable.
“The standard equipment comprising the ‘S’ main boom and ‘W’ luffing jib enables the crane to achieve various boom systems, including a strong Power Boom system with a heavy luffing jib. Only the P adapter is required as a supplement for this purpose. The main S boom operation is possible with a 1,000 tonne head or a 650 tonne head,” a spokesperson adds. The model is fitted with fall protection equipment and stacking supports for lattice sections. It has a component transport width of 3.5 m and a transport height of 3.2 m.
From Liebherr-Werk Nenzing is the LR 1250. Launched in 2013, the model is driven by a 270 kW 6-cylinder diesel engine that meets III B and Tier 4i emission regulations. The crane is fitted with two winches, each with a 12 tonne line pull. The LR 1250 can be transported with boom and counterweight. Also launched in 2013 from Liebherr-Werk Nenzing is the HS 8300 HD duty cycle crawler crane. A spokesperson adds, “To ensure optimum safety, there is a fall protection system which has an automatic locking function. In case of a fall this locking function reacts immediately and prevents impact with the ground.”
Working in confined spaces is another trend that crawler cranes have to overcome. The latest model from manufacturer Link-Belt, for example, is the Tier 4 Final version of its 248 HSL. The 181.4 tonne capacity lattice boom model has a tail swing of 5.15 m, allowing it to work in tight spaces. It is fitted with a high-resolution rear view camera, an audio and visual travel alarm system and a rated capacity limiter (RCL).
Scott Knight, Link-Belt product manager for lattice and telescopic crawler cranes, says, “This 248 HSL comes standard with folding upper guardrails and full-length right and left catwalks with grab handles. The RCL monitoring system provides the operator all critical lift information and allows the operator to set swing and other control parameters.”
From Japanese manufacturer Kobelco is the G Series range of crawler cranes. Models range in capacity from 60 to 250 tonnes and are fitted with Tier 4 engines. The CKE-G series and BME-G series have a switch between dual and independent circuit system, which offers the operator the choice of independent circuits. The system allows hydraulic pumps to drive the main auxiliary hoists and operate the boom independently or dual circuits that use both pumps to drive hydraulic fluid together to operate the hoist motor, the manufacturer says.
Other features include independent and main and secondary hoists, free-fall function, which allows the speed of both winches to be synchronised, and a system that measures the jib angle relative to both the ground and the machine. For ease of transport, models in the series have a nested boom that allows the luffing insert jib to be stored in the middle boom, reducing the number of vehicles needed for transport.
The need for super heavy lift crawler cranes is another area on the rise. “The main applications for these types are mainly the construction of power plants and refineries where heavy loads have to be lifted at large radii,” a spokesperson from Liebherr says. “Large preassembled components and the handling of offshore components at ports are also driving demand.”
Kate Lampson, Lampson International adds, “There is certainly a demand for heavy-lift crawler cranes in today’s market, however, with a change in the current administration’s policies on fossil fuels there could be a lot more.”
The demand for heavy lift crawlers is evident around the world. As a spokesperson from Sany explains, “To realise the nuclear power planning in China by 2020, at least two generator sets should be brought into operation every year. This means that lifting operations would be undertaken simultaneously in multiple projects in which multiple sets of large cranes will be involved. Therefore, in the following few years, the market of large-tonnage crawler cranes will boom due to the restart of nuclear power projects.”
A spokesperson from Terex concludes, “High capacity crawler cranes used to be a rarity but, as structures become ever bigger and weights ever heavier, the need for these cranes increases.”