US refiner HF Sinclair saw profit from its lube and specialty products unit more than double in the second quarter of the year as sales rose faster than costs.

The lube unit’s operating profit of $134.88mn in the three months to end-June more than doubled from $59.93mn during the same period a year earlier.

Profit rose by 10pc from $122.09mn in the first quarter to the highest in at least five years.

Profit got a boost form a 27pc rise in sales of base oils and finished lubricants that outpaced the 17pc rise in the unit's costs.

The unit’s profitability benefited from lubricant prices that kept pace with higher base oils prices during the quarter.

Some lubricant blenders have faced increasingly squeezed margins over the past year as finished lube prices struggled to keep pace with rising costs.

Base oil prices surged in the second quarter of the year amid higher crude prices, even higher diesel prices and tight supply-demand fundamentals.

HF Sinclair’s firm lube prices partly reflected a focus on products like process oils rather than more mainstream products like passenger car motor oils.

The lube unit’s profitability also got a boost from improved integration between the refiner’s base oils supply and its finished lube business.

Other lubricant blenders have highlighted logistical bottlenecks and costs as one of many challenges they have faced over the past year.

The lube unit’s operating profit margin of 15.9pc in the second quarter edged down from 16.2pc in the first three months of the year.

The margin was still up from 9.0pc during the same period a year earlier and was the second highest in more than five years.