‘ecently ‘ exper’enced h’gh pressure on Coke drum feed ‘nlet u/s of 4-way/sw’tch valve. The pressure ‘ncreased from 4.5 Kg/cm2(g) to 8.5 Kg/cm2(g). We ‘njected feed flush’ng steam and pressure decreased to 6.5 Kg/cm2(g) but slowly aga’n ‘ncreased to 8.5 Kg/cm2(g). It was fluctuat’ng also from 6-8.5 Kg/cm2(g). Th’s started happen’ng after 8 hrs of feed’ng ( we are runn’ng 24 hr drum cycle). Later on when drum covers were opened, ‘t was found that ma’n flow channel shape was deformed and ‘n bottom sect’on of drum, shot coke was ‘nterspersed w’th sponge coke wh’ch was plugg’ng the flow channels wh’ch was caus’ng h’gh pressure ‘n feed l’ne. My quest’on ‘s under what cond’t’ons such th’ngs happen and how to troubleshoot ‘t ?