US refiner HF Sinclair Corp saw profit from its lubes and specialty products unit surge in the first quarter of the year amid strong demand for finished products and as prices outpaced rising feedstock costs.The unit’s operating profit of $122.09mn in the first three months of the year was up 83pc from $66.61mn during the same period a year earlier. Gross profit rose by 30pc to $250.43mn..The higher profit mirrored a similar trend among other base oil producers as global base oil prices rose in response to higher feedstock costs more quickly than finished lubricant prices did.The higher profit in turn contrasted with increasingly squeezed margins for lubricant blenders.HF Sinclair’s profit rose even as production of specialty products edged lower in the first quarter from year-earlier levels. But the sales volume of specialty products still rose by 7pc to 35,010 b/d.More than 50pc of that volume consisted of finished products, and 30pc of base oils. The base oils share was the highest in almost three years.The unit’s total sales of $755.01mn in the first quarter rose by 44pc from year-earlier levels. Costs rose even faster, by 52p to $504.58mn.The higher costs squeezed the unit’s gross profit margin to 33.2pc, down from 36.8pc during the same period a year earlier. But it remained well above more typical levels of less than 30pc during the previous four years..US refiner Calumet’s Q1 loss narrows