Fire Pumps

The distinguishing feature of a split case fire pump is that the part of the casing holding the impeller can be lifted off so the inside can be reached. Pumps of this type run on twin bearings and tolerate heavy vibration. Their casings are generally designed to withstand high pressures, and their robustness lets them run at very large water flows.

Water enters the impeller from two separate points, which is why they are called "double suction" pumps. If the water enters unevenly, hydraulic imbalance can damage the pump shaft. For that reason NFPA 20 sets rules for the length of pipe on the suction side of split case double suction fire pumps.

Split case pumps are connected to the motor by a coupling or a shaft, which means they take up considerable space when installed horizontally. Although they cost more than other fire pumps, the split casing makes maintenance easier, which in turn means a longer service life.