Shaft-sealing device and vertical shaft pump equipped with shaft-sealing device

The present invention pertains to a shaft-sealing device for preventing the leakage of a fluid from a shaft-pass-through section of a container through which a rotating-shaft passes. The shaft-sealing device (30) is affixed to a container (2) for separating a high-pressure fluid and a low-pressure fluid from one another, and seals the shaft-pass-through section of a rotating shaft (6), which extends so as to pass through the container (2). The shaft-sealing device (30) is equipped with: a seal casing (33) that has a through-hole (35a) through which the rotating shaft (6) passes, and a sealed chamber (33a) which is connected to the through-hole (35a) and into which the high-pressure fluid flows; and a disc-shaped seal body (31) that is housed inside the seal chamber (33a), integrally rotates with the rotating shaft (6), and has a ring-shaped surface (31a) that is perpendicular to the axial center of the rotating shaft (6). The inner surface of the seal casing (33) which forms the sealed chamber (33a) and faces the ring-shaped surface (31a) of the seal body (31) is a flat surface that is also perpendicular to the axial center of the rotating shaft.