Chief executive Yuan Guangyu said that the deal would be much larger than the takeover of STU from Russia's TNK-BP - its first acquisition abroad - which could be worth anywhere from $10 million to $66m, according media reports.
Global offshore drilling and services are booming because of huge increases in spending by producers trying to cash in on high oil prices, which peaked at $78.77 a barrel this month, and analysts expect the equipment sector to consolidate as players team up to chase the extra dollars.
China Oilfield now views Russia, the Middle East and the Gulf of Mexico as strategic markets it needs to explore. It already maintains a presence in Southeast Asia.
"There's no comparison. The Russian deal is just a taste test, but on this one we're getting serious," Yuan said.
"If we do everything well, the acquisition is likely to happen this year," he added.
China Oilfield had expected the Russian deal to be finalised in April. It got the green light from both companies and the Chinese government, but awaits approval from Russia's government.
"Whether it approves the deal or not, we'll keep trying.
Russia is one of our strategic targets and full of opportunities," Yuan said.
The firm now has operations in more than 10 countries and derived 18 per cent of its revenue from abroad in the first half of this year. It aims to raise that share to 30pc by next year.
To fund its expansion, China Oilfield has applied to regulators to sell up to 820m a shares on the Shanghai exchange. It also sold 1.5 billion yuan ($199m) in bonds. Yuan said the company would continue raising funds if it were to do more acquisitions.