Abstract: A pump for conveying a fluid includes a stationary housing, an impeller conveying the fluid from a low pressure region to a high pressure region, a shaft to rotate the impeller about an axial direction, and a separation device to restrict a flow of the fluid from the high pressure region to the low pressure region. The separation device includes a rotary part connected to the shaft, and a stationary part stationary with respect to the housing. The rotary and stationary parts face each other and delimit a gap between the stationary part and the rotary part. The gap is arranged between the high and low pressure regions. A recess is disposed in the stationary part or the rotary part, the recess including a bottom, and a non-metallic insert is disposed in the recess. A relief channel enables fluid communication between the bottom and the low pressure region.

Abstract: A pump for conveying a fluid includes a stationary housing, an impeller conveying the fluid from a low pressure region to a high pressure region, a shaft to rotate the impeller about an axial direction, and a separation device to restrict a flow of the fluid from the high pressure region to the low pressure region. The separation device includes a rotary part connected to the shaft, and a stationary part stationary with respect to the housing. The rotary and stationary parts face each other and delimit a gap between the stationary part and the rotary part. The gap is arranged between the high and low pressure regions. A recess is disposed in the stationary part or the rotary part, the recess including a bottom, and a non-metallic insert is disposed in the recess. A relief channel enables fluid communication between the bottom and the low pressure region.

Abstract: The present application provides a dynamoelectric machine. The dynamoelectric machine may include a stator, a rotor, and an air gap separating the stator and the rotor. The rotor may include a rotor retaining ring. The rotor retaining ring may include a slanted length extending along the air gap.