Foxconn, the world’s largest contractor of electronic components and principal supplier to Apple, is planning to expand its base for smartphones in China’s central Henan province next year.

The expansion plan, costing 7 billion yuan ($1.1 billion) is expected to bring $20 billion in sales revenue in 2012, state-run Xinhua news agency quoted the commission as saying.

The base will be centered on the Foxconn Science Park in Zhengzhou, provincial capital of Henan, increasing its current production lines to 95, Henan provincial development and reform commission said.

The new plant in Zhengzhou has reached a daily production of 200,000 Apple iPhones and employed 130,000 people, said Mr Guo Gengmao, governor of Henan province.

Foxconn opened new factories in Henan and Sichuan last year, targeting low labour costs and rising markets in the inland provinces.

The company currently employs 1.2 million people, with about one million of them based in the Chinese mainland.

Last year, Foxconn suffered a serious image crisis after a spate of suicides by its workers apparently due to stressful working conditions and poor salaries, after which it revamped its work places and increased remuneration.