The application forms would be coming out for IOCL, BHEL, NTPC, MDL etc in the month of January. Also, the applixation fee would be starting from 100/- to 1000/- but it varies year and PSU wise.
Also, to check the complete information about all the PSUs through GATE, you can go through the below article -
PSU through Gate 2018
Hope this helps!!!
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