China’s oil trading giant Unipec has significantly increased the number of hired tankers to ship a key crude from eastern Russia. China International United Petroleum & Chemical Co., better known as Unipec, has chartered at least 10 tankers so far this month to transport Russian ESPO crude that’s loaded from Kozmino port, according to traders and a shipbroker. That would be a fivefold increase on the number of vessels booked for the trade a month earlier, data from shipping analytics firm Vortexa show. The hired vessels are mostly smaller aframax ships as well as two much larger supertankers, including the Yuan Qiu Hu , which was recently involved in a rare ship-to-ship transfer of ESPO off South Korea. The Russian grade can usually be transported to China on a direct, five-day journey, although its unclear if all the vessels booked by Unipec will deliver their cargoes to Chinese ports. […]