Crude oil prices fell on Monday after U.S. unions called a refinery strike and activity in China’s factory sector shrank for the second month in a row, quashing Friday’s bullish mood. At 0938 GMT (4.38 a.m. ET) Brent crude oil futures were down $1.05 at $51.94 a barrel while U.S. crude futures were down $1.13 at $47.11 a barrel. The move down followed a rally on Friday fueled by month-end short covering and a record weekly drop in the number of U.S. oil rigs employed, according to Baker Hughes. The count is now down 24 percent from its October peak. Both contracts rose by about 8 percent and Brent closed at $52.99 a barrel on Friday. But on Sunday workers at nine U.S. refineries and chemical plants went on strike in a bid to pressure oil companies to agree to a new national contract. “So far […]