UPDATE 1-Valero Aruba repairs seen finished mid-May -sources

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HOUSTON, April 28 (Reuters) - Repairs to the crude oil vacuum distillation unit at Valero Energy Corp's (VLO.N: Quote, Profile, Research, Stock Buzz) 275,000 barrel per day Aruba refinery are expected to finish by mid-May, according to sources familiar with refinery operations.

The sale of the refinery to Brazil's state-owned oil company Petroleo Brasileiro SA (Petrobras) (PETR4.SA: Quote, Profile, Research, Stock Buzz) is expected to take place soon after the repairs are completed, the sources said.

Valero spokesman Bill Day declined to discuss the timing of the repairs' completion.

"We're not saying when the repairs will take place because they are tied to the sale," Day said.

Valero Chief Executive Bill Klesse has said the sale will conclude in the second quarter of this year.

Jorge Zelada, director of international operations for Petrobras said earlier this month the company's board would vote on the purchase in April.

Sources familiar with the talks between the two companies have said Petrobras had agreed in principle to buy the refinery for about $2.8 billion prior to a Jan. 25 fire that damaged the 155,000 bpd vacuum distillation unit. (Reporting by Erwin Seba; Editing by John Picinich)