SINGAPORE, Jan 20 (Reuters) - Top Asian oil and gas producer PetroChina has swapped the portfolios of two top trading executives in a management reshuffle, sources with direct knowledge of the matter said on Wednesday.

The personnel changes, aimed at keeping managers fresh with new challenges, are not likely to alter in a significant way the business strategy of PetroChina's flagship trading vehicle China National United Oil Corp, or Chinaoil, which has reaped record profits in 2020, the sources said.

Zhao Yong, previously president of Chinaoil and who started as one of the firm's founding crude oil traders some 26 years ago, has, since November, become the general manager of PetroChina Fuel Oil Co Ltd.

The unit specializes in fuel oil trading and bitumen production and marketing, and holds a licence to supply bonded marine fuel in the east China a bunkering hub of Zhoushan.

Huo Jinsan, former president of PetroChina Fuel Oil and a veteran in domestic chemicals marketing, has taken Zhao's role.

PetroChina did not respond to requests for comment.

The changes are the latest of in a series of new appointments since 2017, when Tian Jinghui was appointed Chinaoil's chairman.

"The idea is to move around top managers who have stayed in the same job for a long time and take on new challenges," said one company executive, who requested anonymity.

Also among recent moves, Zhang Tong, Chinaoil's former vice president in charge of refined products trading, has been appointed to run the firm's Hong Kong operations which cover fuel trading and retailing in Hong Kong, Macau, Taiwan, Vietnam and the Philippines, as well as financing in Asia.

Zhang, who is going to take on the new role in coming weeks, replaces Wang Zhijun, who has become head of Chinaoil's Kazakhstan unit, the sources said.

In a posting on its official social media account on Tuesday, Chinaoil said it had between 2016 and 2020 traded a total of 2.4 billion tonnes of oil and gas, about 9.6 million barrels of oil equivalent a day, a volume that rivals global traders like Trafigura and Glencore. (Reporting by Chen Aizhu; Editing by Florence Tan and Robert Birsel)