Abstract: Two elongated sealing members are provided to prevent escape of gases from between a movable wall member and an abutting wall member of a metallurgical vessel enclosure. A first elongated sealing member is mounted on the first of the wall members and has a compressible material facing the second of the wall members. A second elongated sealing member is mounted on the second of the wall members and has a blade facing the elongated receiving member. The elongated sealing members are located so that they make contact before the adjoining edges of the wall members are abutted. At least one of said elongated sealing members is movably mounted so that after the elongated sealing members make contact, the wall members may be moved to an abutting position with their adjoining edges touching so as to minimize the effect of heat on said elongated sealing members.