Samsung Electronics said Friday it expects a record operating profit in the fourth quarter of 5.2 trillion won ($4.5 billion), 73 percent up year-on-year thanks mainly to strong smartphone sales. The South Korean firm, the world's largest maker of flat panels, memory chips and flat-screen televisions, was publishing its earnings guidance before official results are released later this month. It estimated sales of 47 trillion won in October-December, a 12 percent rise from a year earlier. The company gave no specific details in its earnings guidance and did not predict net profit. It said estimates may differ from the results because it has not completed an audit. Analysts cited by Dow Jones Newswires said the company benefited from better sales of mobile phones and high-end televisions in the fourth quarter, despite falling prices for chips and flat panels. They said the recent sealing of a deal to sell Samsung's hard disk drive business to Seagate Technology for $1.4 billion in cash and shares also boosted overall income. In the third quarter, the company achieved an operating profit of 4.25 trillion won on sales of 41.27 trillion.