14 and the back 30 of strut 31 fig5 a shows a channel 74 with low profile depth this profile is created by bending a plate and provides for a variable profile depths or avoids depressions in locking devices if existing equipment must be used in the extreme case the sealing element 12 per fig6 is shaped as a flat sheet 32 fig7 shows other embodiment of a coke oven door with spring supported bolts 33 instead of bolts 22 springs 33 are positioned in members 4 and 5 on bolts 33 one spring end is hereby supported by the member surface whereas the opposite end of the spring acts against disc 35 which is mounted on bolt 33 this disc is equipped with a centering boss of about 10 mm in length which protrudes into the inside of the spring the disc can also abut against a boss not shown of the bolt at the other end of the spring 34 this achieves the possibility of assembling spring 34 and disc 35 into members 4 and 5 of the hollow frame with subsequent installation of bolts 33 the bolts can be secured against loss by means of pins at one end fig8 shows a sealing strip preferably of steel instead of soft seal 26 and corner guard 27 the sealing strip is designated as 36 and is bolted continuously with the free leg 14 of sealing unit 2 sealing strip 36 has an angular shape and presses with its smaller leg against.