* New crude unit main feed pipe faces repairs within 12 months
* Overhaul of 80,000-bpd crude unit expected to finish in mid-April
* Overhaul of 90,000-bpd FCCU put off until 2015 (Adds additional work planned, Motiva comment)
By Erwin Seba
HOUSTON, March 28 (Reuters) - The new crude distillation unit at Motiva Enterprises' Port Arthur, Texas refinery has been running at its faceplate capacity of 325,000 barrels per day (bpd) for about a month, sources familiar with operations at the refinery said on Thursday.
The CDU, called VPS-5, was shut for seven and a half months of repairs before resuming production in late January. VPS-5 was the centerpiece of a $10-billion, five-year expansion by Motiva co-owners Royal Dutch Shell Plc (LSE: RDSB.L - news) and Saudi Aramco to boost the refinery's capacity to 600,000 bpd, the largest in the United States.
VPS-5 faces more work within 12 months, however, as the main pipe feeding crude into the unit continues to experience excess vibration, increasing the risk of leaks, the sources said.
The excess vibration on the main crude feed pipe is also preventing Motiva from raising the throughput on VPS-5 to an anticipated range between 360,000 bpd and 370,000 bpd, the sources said.
Most new refinery units are capable of increasing their throughput to levels higher than their start-up faceplate capacity.
Motiva spokeswoman Kimberly Windon said VPS-5 is operating at planned rates. She declined to discuss any work that may be planned for VPS-5 and the status of other units at the refinery.
The sources also said that Motiva expects to finish the overhaul of VPS-2, an 80,000 bpd crude distillation unit, in mid-April, about two weeks later than expected by some media reports but within the window set out by the refinery when it began the work in mid-February.
Motiva may begin the restart of a hydrotreater shut for overhaul along with VPS-2 as early as this weekend, they added. A delayed coker also undergoing overhaul could restart within a week after planned work is completed.
Motiva has put off the planned overhaul of a 90,000 bpd gasoline-producing fluidic catalytic cracking unit until February 2015. The work had been scheduled for February 2014.
VPS-5 began production in late April 2012, but was shut in early June after cracked and pitted pipes in the atmospheric section of the CDU began leaking. The damage was found to be caused by a leak of caustic sodium hydroxide while the unit was shut for what was expected to be a week of repairs.
Leaks in the main crude feed pipe prevented the return to production of VPS-5 in December. Sections of the main crude feed pipe were replaced in early January, making possible the CDU's return to production on Jan. 21. The leaks in the main crude feed pipe were not related to the damage done by caustic leaks.
VPS-5's throughput was slowly raised to 325,000 bpd between late January and late February. (Reporting by Erwin Seba; Editing by Ed Davies and Edwina Gibbs)