Split Case Pumps: High-Flow Double Suction Pumps Built to Service
Double suction split case pumps sized for sustained high flow with a casing that opens for in-line service, supported across the Upper Midwest.
What is a split case pump and where does it belong?
A split case pump is a centrifugal pump whose casing splits along the shaft centerline, so the entire rotating assembly lifts out for service without touching the suction or discharge piping. It usually carries a double suction impeller that balances thrust and moves very large volumes, which makes it the go-to for high-flow, moderate-head duty such as municipal water, HVAC circulation, cooling water, and fire protection. Where large volumes run continuously and downtime is costly, this design earns its place.
Common split case applications
Municipal Water
High-volume transfer and distribution where flow is large and steady.
HVAC and Cooling
Chilled and condenser water circulation for large buildings and campuses.
Fire Protection
Fire service duty demanding dependable, high-flow output on call.
Process Water
Continuous plant cooling and process supply at high flow.
Why double suction matters
Most split case pumps draw flow into the impeller from both sides at once. That double inlet balances the axial thrust on the shaft, so the bearings carry less load and last longer, and it lets the pump handle very large volumes smoothly. The twin inlet also lowers the net positive suction head the pump requires, which helps on installations where suction conditions are marginal. Together these traits are what make the design suited to sustained, high-flow service rather than intermittent duty.
Built to service in place
The split casing is the design's signature advantage. To service the pump, technicians unbolt the upper casing half and lift out the complete rotating assembly, so the impeller, shaft, bearings, and seals all come out without breaking the piping. That access dramatically cuts the downtime of seal and bearing work compared with pumps that must be pulled from the line. For critical continuous duty, that serviceability is often the deciding factor.
Sizing near best efficiency
Because these pumps run continuously at high flow, sizing is about matching the required flow and total dynamic head to a point near the pump best efficiency, where energy cost and vibration stay low over the life of the unit. Verify available net positive suction head against the pump requirement, confirm the driver, speed, and materials suit the water quality and duty, and leave margin so the pump is not run off the end of its curve. An engineer will select against your system curve, not just a duty point.
Split case pump lines available through Brabazon
Brabazon supplies Peerless split case pumps and sizes them against your system curve for water, HVAC, cooling, and fire service. Send the duty and we will match the pump, driver, and materials.
Industries served
When a split case pump is NOT the right fit: for low-flow, high-head, or small footprint duty, a split case pump is oversized and costly. Those services call for an end-suction, multistage, or vertical pump instead. For low-flow or high-head selection, start at the pump category overview and we will point you to the right type.
Repair and rebuild
We rebuild rotating assemblies, replace bearings and seals, and restore wear rings through pump repair and rebuild.
Split case pump questions, answered first
What is a split case pump used for?
A split case pump is used for high-flow, moderate-head duty such as municipal water, HVAC circulation, cooling water, and fire protection. Its casing splits along the shaft centerline so the whole rotating assembly lifts out for service without disturbing the piping. Between the high flow capacity and the serviceable design, it is a workhorse wherever large volumes move continuously.
Why does a split case pump use double suction?
A split case pump usually uses a double suction impeller so flow enters from both sides, which balances the axial thrust and lets the pump move very large volumes smoothly. Balanced thrust means less load on the bearings and longer bearing life, and the double inlet also lowers the net positive suction head the pump requires. That combination is what makes the design suited to sustained high-flow service.
How is a split case pump serviced?
A split case pump is serviced by unbolting the upper casing half and lifting out the complete rotating assembly, so the impeller, shaft, bearings, and seals come out without breaking the suction or discharge piping. That access sharply reduces downtime for seal and bearing work compared with end-suction pumps that must be pulled from the line. It is one of the main reasons the design is chosen for critical continuous duty.
How do I size a split case pump?
Size it by matching the required flow and total dynamic head to a pump curve near its best efficiency point, then verify available net positive suction head against the pump requirement. Because these pumps run continuously at high flow, selecting near best efficiency keeps energy cost and vibration down over the life of the unit. Confirm the driver, speed, and materials suit the water quality and the duty, and leave margin so the pump is not run off the end of its curve.
Talk to a Pump Engineer
Send your flow, head, and system curve and an engineer will size a split case pump near best efficiency, then quote sale or repair. We answer 24/7.
Request a quote or sizing review
Tell us the flow, head, and duty and an engineer will size a Peerless split case pump against your system. Urgent? Call 800.825.3222, answered 24/7.
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