This video walks through the steps to adjust and set end play on a typical vertical hollow shaft pump motor.

EASA service centers looking for options for expansion, or to replace evaporating existing electric motor repair markets, have seen pump repair as a good fit. A majority of EASA service centers currently repair roto-dynamic pumps. Pumps are by far the largest category of machines driven by electric motors. If a service center is repairing electric motors, then it is almost certain that some of those motors are driving pumps, and the prospects for pump repair are its existing customers.

Los centros de servicio miembros de EASA que buscan expandirse o que estén interesados en reemplazar los mercados de reparación volátiles existentes, han visto en la reparación de las bombas algo idóneo. Por lo general, la mayoría de los mismos repara bombas roto-dinámicas. Por mucho, las bombas son la categoría más grande de máquinas accionadas por motores eléctricos.

High vibration is a common problem for motors that are installed on top of vertical pumps. Its source can be a mechanical issue with the pump, motor or coupling or even hydraulic forces from the pump.

 Vertical motors can be identified by their capacity for an external thrust load. One common application with this factor is vertical pumps. The thrust load applied is the sum of the weight of the pump line shaft, the column of water in the casing that is being lifted, the weight of the pump impeller and the thrust produced by the pump’s volutes which forces the water to move upward. The distance between the motor and the impeller can be very short such as pumping from a tank at or above ground level to lifting water from a subsurface aquifer several hundred feet deep. In the latter example, the combined weight of the thrust load can be thousands of pounds (kilograms). The motor must then have a bearing design capable of these loads utilizing thrust bearings. 

Los motores verticales se pueden identificar por la capacidad de soportar cargas de empuje externas. Una aplicación común en la que encontramos este factor son las bombas verticales. La carga de empuje aplicada es la suma del peso del eje lineal intermedio de la bomba (line shaft), la columna de agua que se está levantando, el peso del impulsor de la bomba y el empuje producido por las volutas de la bomba que fuerzan el agua hacia arriba. La distancia entre el motor y el impulsor puede ser muy corta, tal como sucede al bombear agua desde un acuífero subterráneo que se encuentra a cientos de pies de profundidad, hasta un tanque situado por encima o por debajo del suelo. En este último ejemplo, el peso combinado de la carga de empuje puede ser de miles de libras (kilogramos). El motor deberá estar diseñado con un rodamiento capaz de soportar estas cargas, por lo que se utilizan rodamientos de empuje. 

Service centers that provide field service for equipment removal and installation have little trouble handling most common horizontal pumps. However, vertical turbine pumps (and similarly mounted vertical pumps) present some additional challenges.

When motors are installed on top of vertical pumps, high vibration is a common problem. The source of the problem can be a mechanical issue with the pump, motor or coupling, or it can be hydraulic forces from the pump. Often structural issues involving resonance amplify the vibration. An understanding of the nature of this style pump and the various forces is essential to diagnosing and correcting vibration problems on vertical pump motors.