Plug for protecting coke-oven chamber doors from the action of the internal temperature in the oven

Claim 1

A plug for protecting a coke-oven chamber door from heat within the oven, said plug comprising a plurality of vertically stacked refractory bricks mountable on the inside of said door: said bricks having first and second spaced, parallel vertical faces, said second face being abutable with said door and said first face facing away from said door; said faces being joined by side walls, said side walls including short transition portions joined to said first face and converging in a direction away from said door, said side walls having adjacent portions joined to said transition portions, said adjacent portions being longer than said transition portions and converging in a direction away from said door but at a smaller angle than said transition portions, said side walls further including diverging portions joined to said adjacent portions and to said second face, said diverging portions diverging in a direction away from said door, the uppermost brick in said stack having a surface intersecting said first face and side walls which forms a part of the upper end face of the plug and which extends obliquely upward from said first face in a direction toward the door; said diverging portions of said side walls ending below the intersection of said oblique surface and said first face, said plug having a downwardly extending tar discharge chute formed in each side wall of said plug; the lowermost brick in said stack being supportable on said door; the height of an intermediate one of said bricks being selected in accordance with the desired height of said plug; and said bricks having recesses therein receiving a plurality of countersunk bolts extending through said bricks and engageable with said door for fastening said bricks to the door.