(OH) Flexibly coupled pumps feature a separate bearing assembly, in addition to the motor. The vertically oriented impellers are suspended below the support and are submerged into the medium. VS–Vertically suspended pumps– VS pumps are supported above the medium to be pumped. For all pumps of this type, the impeller is placed horizontally, in plane with the bearings.By placing bearings on both sides of the impeller, a better support is achieved. Its advantages are a single bearing housing and a single seal or packing, but an overhung impeller load is a disadvantage.īB–Between bearing pumps– The impellers of BB pumps are suspended in between the supports. The impellers of these pumps can be mounted either horizontally or vertically.

the overhung mass and the rotor dynamic and hydraulic forces. The support has to take care of all forces, e.g. OH–Overhung pumps– The impellers of these pumps protrude from the bearings. The API 610 pumps are primarily divided in three groups: OH, BB and VS. Each of the following pumps types are a sub-category of the API 610 Centrifugal Pump Standard.ĪPI 610 provides a classification for various types of centrifugal pumps. Below are simple definitions for each API pump type. The number is used to differentiate more detailed configuration options within each section. The letters are used to define the main different pump types, where OH stands for Overhung, BB stands for Between-bearings, and VS stands for Vertically Suspended. These are called out by a set of two letters followed by a single number. Within the API 610 Centrifugal Pump Standard, there are various configuration codes for different types of centrifugal pumps. This does not mean that ANSI pumps are unreliable, but rather API-610 pumps have an added aspect of robustness, due to the high temperatures and critical nature of their service. The main focus of the API-610 is reliability, not dimensional interchangeability. It provides design criteria for the design of the actual centrifugal pump, as well as how the centrifugal pump is to be tested, and what type of base it is to be mounted on.ĪPI-610 covers centrifugal pumps, and includes end suction, double suction and other types. API 610 is the API standard relating specifically to centrifugal pumps and centrifugal pumping systems.

Centrifugal pump size chart