April 15 - Pollock & Sons Crane Hire has supplied two six-axle Grove all-terrain cranes to help hoist an 84-tonne barking drum at the Tasman Mill site in Kawerau on New Zealand's north island.

The two cranes - a Grove GMK6400 and Grove GMK6300L - were transported from Pollock & Sons' headquarters in Tauranga, about 100 km from the jobsite, in order to carry out the complex lift.

Before installing the new drum, the old one had to be removed in four loads, each weighing around 62 tonnes. The log decks, which weighed between 35 and 55 tones each, were also removed.

For this project the GMK6400 was configured with a full counterweight of 135 tonnes and its MegaWingLift capacity enhancing attachment, which increases the crane's lifting capacity by up to 70 percent for some boom positions. The GMK6300L crane was also equipped with a full counterweight of 92.5 tonnes.

Once the two cranes had helped remove the old drum, the new piece of equipment, which measured 25 m long and 3.7 m in diameter, was lifted by the two cranes to a height of 13 m.

"Our biggest challenge was bringing the drum between the two cranes and rotating it without touching either boom, which would have resulted in damage," said Carl Hawkins, dispatch operations at Pollock & Sons. "With the two cranes' differing swing radiuses and lift capacities, a considerable amount of time and planning went into the lift."

Once the drum was in place, the chutes that feed logs into the drum had to be installed. Each of the chutes weighs between 50 and 60 tonnes.