BP Whiting refinery to cut output of large CDU for repairs -sources

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HOUSTON, Sept 15 (Reuters) - BP Plc will cut production this weekend by at least 50 percent on the large crude distillation unit for repairs at its 413,500 barrel per day Whiting, Indiana refinery, sources familiar with plant operations said on Thursday.

The work will coincide with the planned shutdown of a smaller CDU and the gasoline-producing fluidic catalytic cracking unit at the refinery for a planned overhaul lasting until early November, the sources said.

A BP spokesman declined on Thursday to discuss operations at the Whiting refinery.

After the news, the U.S. crude front-month discount to the second month widened to as much as 62 cents.

Work on the 290,000 bpd Pipestill 12 CDU is expected to take at least a month to complete, the sources said.

The planned overhaul on the refinery's 90,000 bpd Pipstill 11C crude unit is planned to run until early November as is the overhaul on the 110,000 bpd FCCU 500.

Whiting's 75,000 Pipestill 11A CDU and the 60,000 bpd FCCU 600 will remain in production during the work.

The repairs on Pipestill 12 are expected to focus on the unit's pumps, which have been prone to fouling, the sources said.

CDUs do the initial refining of crude oil coming into a refinery and produce feedstock for all other units. (Reporting by Erwin Seba; Additional reporting by Devika Krisha Kumar in New York; Editing by Chizu Nomiyama and David Gregorio)