Hello

It depends on many factors :

1. From which Department you are from.
2. The PSU that you are applying for
3. No of openings in the PSU.
4. Moreover AIR 1000–1500 will give you the chances of getting into it !
5. And one more thing is that you have to clear the interview.

All PSUs are somewhat similar to each other in terms of salary and benefits. There are certain other factors which you might consider while joining. For Chemical Engineers most vacancies come in IOCL, BPCL, HPCL, ONGC,GAIL. Another good company is EIL but it conducts its own test.

I hope it will help you

Good luck...