SOOTBLOWER LANCE PORT WITH LEAK RESISTANT CARDON JOINT

摘要

A carbon joint (11) is provided for mounting in a wall of a boiler to accommodate a sootblower lance (67) and to allow the lance (67) to be manipulated with respect to the boiler wall. The carbon joint (11) includes a wall box (12) having a central opening (14). An outer ball (15) having a substantially spherical outer surface and a central bore (17) is mounted for axial rotation about a first axis within the central opening (14) of the wall box (12). An inner ball (18) having a substantially spherical outer surface (19) and a central bore (21) is mounted for axial rotation about a second axis within the central bore (17) of the outer ball (15). The first and second axes are mutually orthogonal and the central bore of the inner ball is sized to accommodate the lance of a sootblower. As the lance is manipulated to clean an opposite wall of the boiler, the inner (18) and outer (15) balls rotate about their axes to accommodate the manipulation. Substantially constant gaps (24, 26) are maintained between the outer ball (15) and the wall box (12) and between the inner ball (18) and the outer ball (15) to provide a controlled constant flow of seal air through the gaps (24, 26).