Manitowoc has launched two new crawler cranes sporting variable position counterweight (VPC) technology at ConExpo, three years after first launching a VPC capable crane at the last Las Vegas show.
The VPC was previously available on Manitowoc’s large scale 31000 crawler crane, which, with a 2,300 tonne maximum lift weight, is designed mainly for super large lifts in the energy sector, especially nuclear.
The two new cranes, the 300 tonne MLC300 and the 650t MLC650, are likely to have a wider array of uses, including the energy sector and infrastructure.
The VPC system moves the counterweight laterally from the pivot point in response to the lift weight, in part reducing the total amount of counterweight which must be transported to a lift site, which is ordinarily a major cost on any lift.
The counterweight moves along the rotating bed and is automatically positioned based on changes in boom angle. Other advantages include reduced ground preparation, lower ground-bearing pressure.
The counterweight boxes are also designed to be common across multiple crane platforms.
“The VPC is game-changing technology,” said John Kennedy, SVP crawler cranes. “This new technology will have a significant impact on the lifting industry, as it enhances crane capacities, reduces mobilization time on the job site, and in the end, saves customers a significant amount of time and money.”
Kennedy said that both cranes are ideal for energy-related projects, including refineries, petrochemical installations, and power plants, as well as infrastructure applications. The smaller footprint plus the Variable Position Counterweight system enable the cranes to easily move around a job site, and a VPC-MAX capacity enhancing attachment allows increased capacity for heavy lifts that would usually require a wheeled-type lift enhancer.
The MLC300 features 96 metres of boom and has the option of a fixed jib attachment of 30m. A 96m luffing jib can be added to extend its reach to 144m. Meanwhile the MLC650 has a 104m main boom to which a 30 m fixed jib can be added. A 101m luffing jib can be added to reach a maximum 157m .
The VPC-MAX attachment increases capacity and boom and jib combination lengths, which for the MLC300 translates to a maximum boom and luffing jib combination of 168m, while for the MLC650 the boom and luffing jib combination stretch out to a total of 205 m. The MLC650 maximum capacity increases to 700t with the VPC-MAX installed.
The ground preparation area needed for the MLC300 using the VPC-MAX can be only one-tenth of that required by competitive cranes.
Manitowoc had previously revealed that it was working on developing two smaller VPC crawler cranes in court documents released in its patent stoush with Sany over the variable position counterweight technology, which it alleges Sany has infringed with its SCC8500 crawler crane.