Guangzhou, Aug. 4 -- When Mr Sun Huihai first began working at a factory in the southern manufacturing belt of Guangdong some 13 years ago, his colleagues were all humans.

Now, they are joined by more than 200 robots that can work around the clock, seven days a week, to help produce air-conditioners for home appliances giant Midea.

Rows of bright orange robot arms whir at all hours of the day, fishing freshly pressed plastic parts out of hot metal moulds and onto a long conveyor belt.

Driverless robots with blinking lights store these parts in a multi-storey warehouse, and later take them to be assembled into units that are sold in China and around the world.

The number of robots put to work on the factory floor increases every year, ...