SHANGHAI, July 12, 2016 (Xinhua) -- Visitors watch the robot welding system during the Aluminium China 2016 at the Shanghai New International Expo Center (SNIEC) in Shanghai, east China, July 12, 2016. The Aluminium China 2016 started at the SNIEC on Tuesday, attracting more than 400 enterprises in aluminium industry from over 30 countries and regions. (Xinhua/Fang Zhe)