The bridge of the polar crane for unit 1 of the Haiyang nuclear power plant in China's Shandong province has been raised into position near the top of the AP1000 reactor building.
|The bridge of the polar crane is lowered into place at Haiyang 1 (Image: SNPTC)
The 350-tonne bridge was successfully raised into place on 23 March, State Nuclear Power Technology Corporation (SNPTC) reported. Sitting on a circular rail, it can rotate 360 degrees and will be used to lift reactor components and main pump components.
A trolley and lifting mechanism will now been installed on the bridge to complete the crane, after which the dome of the reactor building can be built on top of the containment walls, marking a major milestone.
Polar cranes are used in pressurized water reactors to lift reactor vessel heads, internals, and a multitude of lighter loads during refuelling outages. In some plants the polar crane is also used to lift the reactor vessel itself and the steam generators during construction.
The AP1000 polar crane is almost 38 metres long, 13.5 metres wide, and weighs more than 450 tonnes. It has a main hoist capacity of 300 tonnes and an auxiliary hoist rated at 25 tonnes. The bridge has a rated capacity of 800 tonnes to enable it to support special construction lifting equipment if necessary.
Haiyang 1 is the second Westinghouse-designed AP1000 reactor under construction in China, following Sanmen 1. Two AP1000 units are under construction at each site, with third and fourth units planned.
Researched and written
by World Nuclear News