Manitowoc 31000 in largest ever lift
Crawler in 650t pick and carry in South Korea
Manitowoc Crane’s range-topping 31000 crawler crane, the largest crane it has ever built, has carried out its biggest job to date – a pick and carry lift of a 650 t cold box at a liquefied natural gas plant in Gwangyang, South Korea.
The recent lift took place at the Posco E&C plant where the 2,300 t (2,535 USt) capacity crane, which is the first 31000 in the field, has been working since March.
The 31000’s design means it can be disassembled, moved and re-assembled in just four weeks. As a result, it has a busy schedule of upcoming and ever-increasing lifts at the site, with a 900 t pick scheduled for November and two 1,000 t lifts due to take place in December and February.
The Manitowoc 31000 is owned by South Korea’s Chunjo Construction Co., one of the world’s biggest crane rental companies.
The crane is equipped with Manitowoc’s Variable Position Counterweight (VPC) system, which moves the position of the counterweight further back from the centre point when under heavier loads. This lift was the first to utilise the VPC technology.
“It’s great to see this flagship crane performing, making an awkward lift look easy,” said Chang Hwan Jang, chairman at Chunjo. “The 31000 has a minimal footprint thanks to its VPC but also offers a huge capacity, so it fits our needs perfectly. We are delighted with how well the crane is performing and look forward to seeing the next challenging lift it tackles.”
The Manitowoc 31000 lifted the 55 m tall cold box, which measures 9 m by 9 m, off a flat-bed trailer in tandem with a 600 t capacity Manitowoc 18000, also owned by Chunjo. Once airborne and upright, the 31000 took over and carried the load to its final location. The entire operation took less than two hours.
The tight lift was hindered by a high wall to the side of the 31000 that restricted its movement. To avoid this, the crane’s entire 55 m boom was raised to its highest angle, bringing the load closer to the crane and minimizing potential swing. The crane is also fitted with a 36 m luffing jib.
The VPC system minimizes the crane’s footprint and ground preparation by suspending the counterweight in mid-air, rather than using a wheeled counterweight trolley, found on other high-capacity crawler cranes. The VPC automatically positions the 31000’s counterweight to fit the required lift and ranges from 8 m fully retracted to 29 m fully extended.
Since arriving at the plant, the Manitowoc 31000 has completed a range of challenging lifts around the congested site. Two of the previous largest lifts included placing reactors that weighed 250 t and 450 t each. Manitowoc Crane Care engineers work closely with Chunjo to support its operators throughout its major lifts.