UPDATE 1-BP's Whiting, Indiana refinery to shut large CDU for up to 10 days - sources

(Adds details on CDU outage, company no comment)

HOUSTON, Sept 16 (Reuters) - BP Plc plans to shut thelarge crude distillation unit for up to 10 days of repairs atthe company's 413,500 barrel per day (bpd) Whiting, Indianarefinery, Midwest trade sources said on Friday.

A BP spokesman declined to discuss operations on Friday atthe Whiting refinery.

Repairs on the 290,000 bpd CDU, called Pipestill 12, areexpected to begin early next week, coinciding with the plannedshutdown of a smaller crude unit and the refinery'sgasoline-producing fluidic catalytic cracking unit, sources havetold Reuters.

Sources familiar with plant operations said on Friday theyunderstood Pipestill 12 would only be partially shut, reducingthe unit's production by up to 50 percent.

If Pipestill 12 is only partially shut, the repairs may takea month to complete, the sources familiar with operations saidon Thursday.

The planned overhaul on the refinery's 90,000 bpd Pipestill11C crude unit is planned to run until early November as is theoverhaul on the 110,000 bpd FCCU 500.

Whiting's 75,000 Pipestill 11A CDU and the 60,000 bpd FCCU600 will remain in production during the work.

The repairs on Pipestill 12 are expected to focus on theunit's pumps, which have been prone to plugging up the pump, thesources said.

CDUs do the initial refining of crude oil coming into arefinery and produce feedstock for all other units. (Reporting by Devika Krishna Kumar and Scott DiSavino in NewYork; Erwin Seba in Houston; Editing by Diane Craft)