DavyMarkham sends 320t cutterhead to China

Sheffield heavy engineering company DavyMarkham has manufactured a 320t cutterhead for a 12.4m diameter tunnel boring machine (TBM) and despatched it the mountains of Sichuan Province, China.

On arrival, the cutterhead will be mated to the rest of the TBM manufactured by The Robbins Company of Ohio, and will be instrumental in building the new 4,800MW Jinping II hydropower station on the Yalong River.

The £1.15m head was fabricated in six sections, the heaviest of which is 60t, and test assembled at DavyMarkham’s works.

Robbins will fit the head to the TMB in a massive underground launch chamber, pre-excavated by drill and blast methods. Once assembled, the TBM will create a headrace tunnel almost 17km long (one of the longest in the world) to deliver water under pressure to the turbines.

Once completed in 2010, the new installation will be the Ertan Hydropower Development Company’ largest power station and transmit electricity to many eastern provinces and cities like Shanghai and Beijing.