A pump casing is an outer shell of a pump meant to seal off internal components from the outside atmosphere while maintaining desired fluid pressure and preventing leakage. There are different casing constructions depending on the pump type, and each serves a distinct function.
Split case pumps are aptly named for their either vertical or horizontal split which provides easy access to internal parts, allowing for easy maintenance. Read on to discover how these split case pumps work and other advantages of this unique casing design.
Split case pumps have casings that come apart, making it easier for a technician to access the pump internals without disturbing the drive. These pumps have a between-the-bearings design, where the impeller has bearings on both sides. As a result, it makes the impeller much more planted under stress, making split pumps more efficient than frame-mounted pumps.
There are two types of split case pumps based on the axis of division:
Due to their design, vertical split case pumps have a minimal footprint compared to other pumps with similar capacities. However, they are not so popular as they tend to have lower efficiency. Vertical split cases are suitable for transporting high-pressure, high-temperature fluids.
Horizontal split case pumps are most common as they exhibit higher efficiencies (above 90%) and are more accessible to service. With a between-the-bearings configuration, these pumps are also stable at variable speeds and can work with various suction orientations.
Split case pumps are expensive and not as flexible as standard pumps. However, they are still used across different industries because of their reliability and performance. In addition, features like in-between-bearing designs enable these pumps to keep on working for more extended periods without needing frequent maintenance.
Also, they are the only type of common pump that features a double suction impeller. This allows the pump to suck in fluid from both sides of the impeller, further reducing the load on the pump bearings and offering excellent NPSH values.
Vertical split case pumps are typically used in industrial applications like oil and water supply, ballast, and cooling. On the other hand, horizontal split case pumps are the most common and used for pumping low viscosity fluids at low to medium pressure, like water. Hence, these types of split case pumps are used in municipal pumping stations and cooling tower stations, where they require water at constant pressure, and the pump needs to keep working for longer periods.
Deciding on a split case pump requires factoring in several variables. For example, you may need to determine whether you need single-stage or multistage split pumps. Does your split case pump also need to handle high pressure? What will be the best configuration? At Hayes Pump, we make it easy for our customers to choose the right pump for their unique fluid transportation requirements.