Hii aspirant ,

Coming to your question I would like to tell you that after getting a good rank in the gate from mechanical engineering the different psu you can get is the ,

• Bhabha atomic research centre 
• DRDO 
• Oil and natural gas( ONGC )
• Indian oil corporation of India ( iocl)
• Mazagon dock shipbuilders 
• HPCL 
• Delhi development authority.
• NTPC 

These are the some top psu which recruit the mechanical engineers ,

Hope this helps you ,

Good luck.

• Bharath Heavy Electricals Limited - BHEL
• Hindusthan Petroleum Corporation Limited - HPCL
• Gas Authority of India Limited - GAIL
• Indian Oil Corporation Limited - IOCL
• Bharath Petroleum Corporation Limited - BPCL
• Oil And Natural Gas Corporation - ONGC