Samsung Electronics expects to almost double operating profit year-on-year in Q3 as the South Korean vendor continues to benefit from strong sales of its Galaxy smartphone range.

The firm guided that operating profit would come in at KRW8.1 trillion (US$7.2 billion) in Q3, up from KRW6.72 trillion the previous quarter and KRW4.25 trillion a year ago.

The operating profit is well ahead of an average forecast of KRW7.6 trillion in a Reuters survey of 16 analysts. Samsung estimated Q3 revenue at KRW52 trillion, in line with market forecasts of KRW51.7 trillion. It is scheduled to publish full Q3 results on 26 October.

According to Reuters, the figures would represent a fourth straight record profit quarter for the firm – but it predicts that the run could come to an end in Q4.

It says that Q4 could be impacted by Samsung having to spend more on marketing to counter Apple's latest iPhone and other rival products, and it may also need to put money aside to appeal the recent court ruling that awarded more than US$1 billion in damages to Apple for patent infringements by Samsung.

Profit from the mobile division is likely to have more than doubled to around KRW5 trillion on the back of an estimated 58 million smartphone sales, with the flagship Galaxy S3 (pictured) accounting for about a third of shipments.