Hello arwaz,

Cut off for any college depends on the number of seats available in a college, difficulty level of the question paper, and the performance of other candidates so they change every year. Your admission in BIT, BHILAI will be determined according to the category to which you belong to. For the unreserved category closing rank(CR) was 295, for ST category was18685, for SC category was 5308, for OBC category was 630. 

For any further information regarding this please refer to the following careers360 link.

https://www.google.com/amp/s/engineering.careers360.com/articles/cg-pet-cutoff/amp

Hope this information was helpful.

Good luck!