Other than GATE there are various other exams such as :

Bhabha Atomic Research Centre ( BARC)

Bharat Heavy Electricals Limited ( BHEL)

Fertilizers and Chemicals Travancore Limited (FACT)

Indian Rare Earths Limited ( IREL)

Madras Fertilizer Limited (MFL)

Energy Efficiency Services Limited (EESL)

Coal India Limited (CIL)

Vikram Sarabhai Space Centre (VSSC)
BHEL recruits through GATE also.

All the best!!

HI,

SEE GATE i.e graduate aptitude test in engineering is a national level entrance test, which score is evaluated to take admission in tier 1 colleges like iits, nits , bits etc. psus like ongc, iocl, ntpc like organizations hires engineers based on gate score. also some times individual recruitment comes from companies like tata motors, tata chemicals, also you may apply for public service commission exams which conducts by different state wise exam authority.