The invention relates to a shaft bearing having a seal arrangement to prevent steam leakages that can occur in the event of temperature fluctuations or pressure fluctuations between a liquid medium on the one side and a gaseous medium on the other side of the compact bearing, wherein, between a primary radial seal and a rotation bearing portion, a lubrication space surrounding a shaft circumference is arranged that receives a volume of lubricating grease that has a higher viscosity than a lubricating oil and a coolant; and a volume compensator for compensating a temperature-dependent volume fluctuation is provided that comprises a compressible material, and is arranged vertically in interaction with the volume of the lubricating oil and/or the volume of the lubricating grease.