* Motiva plans overhaul at Norco, La. refinery in Oct
* Phillips 66 to replace Ponca City coke drums (Consolidates earlier stories about refinery maintenance)
By Erwin Seba
HOUSTON, Aug 8 (Reuters) - Several refiners on the U.S. GulfCoast and in the Midwest have planned large-scale overhauls forthe fall as well as making longer-term maintenance plans thatwill temporarily crimp gasoline supplies in parts of the UnitedStates, sources familiar with operations at the refineries said.
The four refineries having work done in the autumn have acombined crude oil capacity of 761,900 barrels a day. Thatamounts to about 4 percent of U.S. refining capacity, thoughwork at other refineries is also likely and the work will nottrigger total shutdowns of the plants.
One of the largest projects planned for the fall is theoverhaul Motiva Enterprises plans for its 233,500barrel per day (bpd) Norco, Louisiana, refinery.
The company has twice re-set the date for the start of thework, which will include a crude distillation unit and agasoline-producing residual catalytic cracking unit, sourcesfamiliar with operations at that refinery told Reuters.
The work is now set to begin Oct. 1, the sources said. Thecompany changed the date, looking to maximize output before therefinery is shut.
A Motiva representative was not immediately available todiscuss refinery operations.
Also planning an extensive overhaul is Phillips 66,which is set to replace giant coking unit drums at its 198,400bpd Ponca City, Oklahoma, refinery in October, said sources withknowledge of Phillips' plans.
During the overhaul, the coking unit, which boosts theproduction of motor fuel from a barrel of crude oil, will beshut for at least four weeks.
A Phillips 66 spokesman declined to discuss the refinery'splans.
Total Petrochemicals and Citgo Petroleum Corp both plan reformer overhauls at their refineries inTexas in September, sources at those plants said .
Citgo will also shut a BTX unit, which processes refiningby-products benzene, toulene and xylene, at the company's163,000 bpd Corpus Christi, Texas, refinery.
2014-2015
In the longer term, Total plans a crude distillation unitoverhaul in either late 2014 or early 2015 at its 167,000 bpdPort Arthur, Texas, refinery.
In the first quarter of 2014, Valero plans to shut a crudedistillation unit, a reformer and an sulfur recovery unit at its180,000 bpd Memphis, Tennessee, refinery.
The work, scheduled for March, will shut half the refinery'sproduction for up to four weeks.
BP Plc's 405,000 bpd Whiting, Indiana, refinery isscheduled to shut a gasoline-producing fludic catalytic crackingunit in first half of 2014 for an overhaul, said sourcesfamiliar with Whiting refinery operations.
Projects that have yet to be scheduled are Valero's plannedcrude oil capacity expansion at its 156,000 bpd McKee refineryin Sunray, Texas.
The company hopes to have a permit to go forward with theproject by the end of the year. Valero plans to add 50,000 bpdin crude oil refining capacity. Valero first announced its plansin 2011.
Valero spokesman Bill Day said the company was awaitingpermits from Texas regulators to begin construction.
"Once we are permitted, construction can begin fairlyquickly," Day said.
Another project expected within the next few years, but notyet begun is integration of Tesoro's Corp's two Los Angelesrefineries.
Tesoro has said it plans to integrate the newly-acquired246,000 bpd Carson, California, refinery with its 103,800 bpdWilmington, California, refinery.
A Tesoro spokeswoman declined to discuss plans for the tworefineries. (Reporting by Erwin Seba; Editing by Terry Wade and DavidGregorio)
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