A calculation method of high temperature cut-off butterfly valve for catalytic flue gas and its sealing surface

Abstract

The invention discloses a high temperature stop butterfly valve for catalysis smoke. The high temperature stop butterfly valve comprises a valve body (1), a valve plate (2) and a valve shaft (3). A medium runner (4) is arranged in the valve body (1). A shaft support structure is arranged in a stepped hole (6). A shaft locating ring (10) is fixed in a small hole of the stepped hole (6). One end ofthe locating ring (10) stretches into the medium runner (4). A bearing outer ring (8) is arranged in a large hole of the stepped hole (6). A spherical groove (13) is formed in the bearing outer ring (8). A bearing inner ring (7) capable of rotating around the axis of the spherical groove (13) is arranged in the bearing outer ring (8). An installing hole (14) penetrating through the bearing inner ring (7) is formed in the middle of the bearing inner ring (7). The high temperature stop butterfly valve has the beneficial effects of being compact in structure, reliable in operation, tight in sealing and long in service life.

Description

Technical field [0001] The invention relates to the technical field of cut-off butterfly valve structures, in particular to a high-temperature cut-off butterfly valve for catalytic flue gas and a calculation method for the sealing surface of its sealing ring. Background technique [0002] At present, the butterfly valves used for shut-off mainly include butterfly valves with single eccentric, double eccentric and triple eccentric structures, and the structure that can realize metal-to-metal close breaking is only a triple eccentric structure. Because the existing metal-sealed butterfly valves used in high temperature conditions have defects in sealing performance and flexibility of action, butterfly valves are rarely used as a form of tight shutoff under high temperature conditions. However, due to the large-scale modern industrial equipment, There is a need for a large-diameter high-temperature cut-off valve with compact structure and light weight. Because the existing butterfl...

AI Technical Summary

Problems solved by technology

Because the existing metal-sealed butterfly valves used in high-temperature conditions have defects in sealing performance and operational flexibility, butterfly valves are rarely used as a form of strict shut-off under high-temperature conditions. However, due to the large-scale modern industrial equipment, There is a need for a large-diameter high-temperature cut-off valve with a compact structure and light weight

Because the existing butterfly valves are not combined with the high-temperature operating conditions of the valve in terms of shaft support, sealing pairs, and system rigidity, they cannot adapt to the operating requirements above 400 °C

Because the temperature of the circulating medium is high, the valve shaft will elongate in the axial direction after being heated, which will drive the valve plate installed on it to move, and eventually the sealing ring on the valve plate will be in close contact with the valve seat, resulting in the failure to open the valve. In addition, after the sealing ring is worn for a long time, there will be a gap between the sealing ring and the valve seat, resulting in a loose seal and reducing the service life of the valve.

Moreover, due to the high pressure of the circulating medium, the valve shaft is completely deformed, and the journals at both ends of the valve shaft are stuck in the bearings, resulting in a stuck phenomenon. Therefore, the existing cut-off butterfly valve cannot be applied to the operating requirements at temperatures above 400 °C.

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