Abstract: A vented coke oven door includes a door frame having a vertical face surface carrying a plug assembly having a central vertical internal opening to conduct coke oven gas generated at the bottom of a coal charge in a coke oven chamber. The plug assembly includes a plurality of U-shaped refractory plug segments arranged in an end-to-end aligned relation with leg sections of each U-shaped segment extending horizontally into an abutting relation with the face surface of the door frame. Each leg section carries either an embedded hooked end or a T-shaped head of a threaded fastener which is supported by the door frame so that the leg sections are unrestrained against movement toward and away from each other in response to a thermal gradient across the wall thickness of the refractory plug segment.