Reliance Industries Ltd plans to shut one of its four crude distillation units (CDU) for regular maintenance in March, the company said.
The CDU will be shut from March 20 for about 3-1/2 weeks, the company said in a statement without specifying the unit's capacity.
Reliance also plans to replace a catalyst at a vacuum gasoil and naphtha hydrotreater.
"The rest of the refinery will continue at normal levels of operations," the company said.
Reliance operates two refineries in Jamnagar with a total capacity of 1.24 million barrels per day (bpd), making this one of the world's largest refining complex in a single location.