Hard facing, dismantling and re erection of pipes, bends, elbows, T pieces or transition pieces of above classifiers, replacement or reversing of orifices in PF lines and tilting of straight PF lines for worn out pipes, replacement of worn out straight pieces in PF lines by removing matching flanges and welding to the new pieces of PF lines of Units 5 and 6 during the AOH period 2022-23