Motiva shuts Port Arthur refinery's 2nd largest CDU after leak -sources

(Updates with Shell (LSE: RDSB.L - news) statement)

HOUSTON, Feb 17 (Reuters) - Motiva Enterprises shut its 195,000 barrel per day (bpd) crude distillation unit, the second largest at its Port Arthur, Texas, refinery, on Tuesday morning due to a leak in a pipe, said sources familiar with plant operations.

Traders said shutting of the VPS-4 CDU at the 600,250 refinery, the largest in the United States, will be bearish for U.S. crude futures.

A Motiva spokesman said there was an operational upset on a unit at the Port Arthur refinery.

"There were no injuries associated with this situation," said Motiva spokesman Ray Fisher. "All appropriate agencies were notified. For reasons of commercial confidentiality, we do not provide details about the operational status of individual units or information on supply."

Crews were trying to determine exactly which part of VPS-4's piping was leaking and how long it might take to fix it, the sources said.

The shutdown of the CDU will back out more crude in the Houston area, putting pressure on cash differentials because of the abundance of oil already available in the U.S. Gulf Coast, traders said.

That extra supply will likely slow down flows into the region, including TransCanada Corp (Toronto: TRP-PA.TO - news) 's Marketlink pipeline and Enterprise Products Partners LP's Seaway and Seaway Twin pipeline.

Production has been slowed on several other units at the refinery due to the shutdown of VPS-4 on Tuesday, the sources said.

The Port Arthur refinery's 60,000 bpd hydrocracking unit called HCU 2 was shut on Monday due to a leaking seal on the unit's compressor, sources said.

Motiva is also performing a planned seven-week overhaul of the Port Arthur refinery's 92,000 gasoline-producing fluidic catalytic cracking unit. Units (HKSE: 0405.HK - news) associated with the FCCU, including an 18,000 bpd alkylation unit and a 49,000 bpd catalytic reformer are also shut as part of the work, which began on Jan. 13.

Motiva is a 50-50 joint venture between Royal Dutch Shell (Xetra: R6C1.DE - news) Plc and Saudi Aramco.

(Reporting by Erwin Seba in Houston and Catherine Ngai in New (KOSDAQ: 160550.KQ - news) York; Editing by Chizu Nomiyama, Marguerita Choy and Cynthia Osterman)