A major milestone was reached at the China-built K-2 reactor in the Karachi nuclear power plant in Pakistan, when so-called cold functional tests began on Nov 26, according to local reports.

Cold functional tests are carried out to confirm whether the main system and its supporting facilities are properly installed and ready to operate under high-pressure conditions.

The K-2 is the first overseas unit using Hualong One (HPR 1000) nuclear technology, a domestically developed third-generation nuclear reactor design.

It was built by China Zhong Yuan Engineering Corporation, or CZEC, a unit of China National Nuclear Corporation, also known as CNNC.

Officials from the Pakistan Atomic Energy Commission, CNNC, China Nuclear Engineering & Construction Group Corporation and CZEC attended the launch ceremony for the test.

Experts said that the test marked the point where the K-2 reactor has entered the commissioning stage, advancing from the installation stage.

Until now, the K-2/K-3 project has been safely under way for more than 2,080 days.

Officials said it had reinforced the increasing confidence being felt in the home-grown Chinese nuclear technology by countries involved in the Belt and Road Initiative.

HPR 1000 is the 3rd-generation nuclear power brand to which China has exclusive intellectual property rights. Officials said it is a demonstrative flagship project, powering China's nuclear power technology to go global.

Cold functional tests of the China-built K-2 reactor at Karachi nuclear power plant in Pakistan begin on Nov 26. [Photo/CNNC]