K Srinivas, Senior Manager of SMS Department, passed away this morning at the hospital, company sources said.
The explosion had occurred at the 'oxygen control unit' near the Steel Melting Shop-II at the plant on Wednesday night.
Some senior members of the managerial staff, alongwith workers, were among the victims.
The deceased include Deputy General Manager (Construction) L Srihari and Deputy General Manager (instrumentation) P V Karunakar.
General Manager (Projects) D S Kalsi and Assistant General Manager (SMS) M B R S Sarma, who were critically injured, have been shifted to Mumbai. A total of seven people are still undergoing treatment.
Union Steel Minister Beni Prasad Verma had yesterday ordered an high-level inquiry into the mishap.