JULY 5, 2013 — Cargotec subsidiary MacGregor has won the contract to deliver North Star, the jewel-shaped, glass capsule that will lift passengers on Royal Caribbean's new Quantum Class cruise ships more than 300 feet above the ocean for spectacular 360-degree views (see earlier story).
North Star's 7.1 tonne viewing gondola will be lifted by an electro/hydraulically-driven MacGregor slewing crane with an outreach of 41 m. It will be able to accommodate 14 guests and one crew member and will be fitted with a stabilizing system that will ensure that it remains level with respect to the vessel's deck and will also damp gondola movements, providing a comfortable ride for the guests.
The crane's slewing function will also allow the viewing gondola to be swung out over the sea.
"We are the first crane supplier involved in anything like this type for a cruise ship," says Jonas Hägglund, MacGregor Sales Manager. "Safety is paramount, and the operator needed a crane supplier that would not only deliver the highest safety standards, but also proven, reliable technology for the North Star guest experience."
The system is designed for 100 percent redundancy with two separate power units, each large enough to drive the crane in reduced speed mode; it will also be provided with a diesel-driven emergency power pack. Additional safety features include automatic cut outs and safety valve overload protection on all crane motions. The crane is designed to standards set by German technical certification company, TÜV süd.
North Star will be controlled using a separate PLC safety system in addition to a MacGregor CC3000 crane control system.
"The CC3000 provides excellent load control and can easily be adjusted with a laptop computer for different parameters, such as speed ramp times," says Mr. Hägglund. "All crane movements will be smooth and immediate, with stepless speed control, essential for this type of guest experience. It is also important that the experience is as quiet as possible, so the main power pack will be rubber-suspended to minimize vibrations and noise transmission; the crane housing will also be isolated to minimize noise.
"Given the vessel's cruising areas, the system is fitted with an air-type cooler to keep the crane's hydraulic oil at a moderate temperature even in very hot ambient conditions; this ensures a long oil life and reliable crane performance," he adds.
The two 167,800 grt, 1,141 ft (348 m) 4,180 passenger Quantum class ships are under construction at Meyer Werft. The first, Quantum of the Seas, is set to enter service in fall 2014, sailing out of New York Harbor from Port Liberty. Sister ship Anthem of the Seas is scheduled for delivery in spring 2015