Group executive vice-president Koon Poh Min said that the company had invested RM3bn ($953M) in the new plant.
He said the higher combined production would go a long way towards helping the company realise its goal to emerge as a global supplier of ingots and billets.
The first plant, sited 38km from Mukah, Malaysia produces 120kt/y. The Mukah plant, which started production in August 2009, is a joint venture with Japanese industrial giant Sumitomo Corp.
The two plants are operated by Press Metal Sarawak, a subsidiary of Selangor-based Press Metal Bhd
Both plants used Aluminium Corp of China's technology, which is also used in 215 aluminium smelters worldwide.
Koon said the domestic market accounted for half the company's current production, while the balance was exported to Japan, South Korea and the growing economies in the Asia-Pacific.
He said the Mukah plant, which employs 800 workers on three shifts, was in the midst of installing a third production line to produce a new product called A356 used to manufacture alloy wheels.
Source: The Star, Kuala Lumpur