Abstract: A coke oven door, which includes a metal frame, means for latching the door in a closed position, a sealing member extending around the perimeter of the frame having forward edges adapted to contact a sealing surface on a coking chamber door jamb for effecting a continuous seal. The coke oven battery also having at least one attached protrusion proximate the coking chamber extending outwardly from the battery, such as a latch or a guide bar, said door comprising a door plug passing with clearance and fitting into the coke oven, said plug having an inner surface that forms an interior end wall of the coke oven wherein a first plane is formed by the perimeter of said inner surface.

Abstract: In the fabricating of a mandrel bar, a plurality of used mandrel bar segments are provided, each of which has a central bore comprising a smooth surface portion and a threaded portion. Each segment has a circumferential recess at an end thereof and a bevelled surface adjoining the recess and extending inwardly of the segment at an angle to the vertical. A coupling has a smooth central boss section and threaded ends. A connection is made by threadedly connecting the ends of the coupling with a pair of opposed mandrel segments, with the smooth boss of the coupling fitting inside the smooth portion of the bore of each segment to effect, with the threaded joint, a straight, tight joint. A weld groove of gull-shaped cross-section is provided between the opposed ends of a pair of mandrel segments, having a body portion formed by a pair of opposed bevelled surfaces and wings formed by a pair of opposed recesses.