When it comes to pumps, the term “head” refers to the height a pump will push liquid up into the air. A high-head pump produces more pressure and will push liquid up further – whereas a medium head pump has more flow, but less pressure and therefore will not push the liquid as high.
Low flow high head capability in centrifugal pumps is required in many critical applications in the hydrocarbon, petrochemical, chemical, power generation, gas production, and specialty processing industries.
Sundyne makes Low Flow High Head Pumps in two main configurations:
- Vertical Low Flow High Head Pumps – are used in cases where one stage is enough to reach the desired high head. Motors are mounted directly above the pump or supported by a motor stand, depending on the power.
- Horizontal Low Flow High Head Pumps – are used for larger motor sizes or multistage configurations.
High-speed integrally geared pump designs offer numerous advantages over multistage pumps, including:
Compactness:
Single stage designs or designs with fewer and smaller stages achieve the required high head. A compact design calls for shorter shaft spans resulting in lowered shaft deflection and improved shaft dynamics. This contributes to the high reliability of high-speed centrifugal pumps. Compactness of the pump contributes to a more economical solution, especially when special metallurgies are required for harsh applications, reducing weight with smaller pump cases and seals. Lower installation costs are also realized with a smaller footprint and foundation costs.
Simplicity:
Maintenance of a low flow high head centrifugal pump is quick & easy due to fewer parts than multistage pumps. Single stage and inherently larger clearances reduce shimming and lengthy fitment. The number of spare pump parts to keep in inventory is also greatly reduced.
Highest Efficiency:
Low flow high head pumps running at higher speeds offer by far the best efficiency in the low flow ranges with reduced disk (impeller) friction losses. Hydraulics are custom-sized for every pump to exactly match BEP to customer conditions. An optional inducer is used to address applications with low available Net Positive Suction Head (NPSHa).
Robust Design:
Low flow high head pumps offer a robust design. Large impeller clearances are tolerant of upsets and they enable the pump to handle soft slurries.
Ease of Re-rates:
Low flow high head pumps can be easily re-rated, if the process conditions change over time, by changing the combination of impeller, diffuser, speed and inducer geometry.
For more information on Sundyne’s Low Flow High Head Pumps, please visit:
About the Author:
Hélène Balligand is Sundyne’s Pump Product Line Manager. She oversees Sundyne’s Low Flow High Head product management activities, with a focus on customer & market needs, as well as growth & profitability of Sundyne’s flagship products.
