I. Complete Classification System of Pumps
To determine the category to which a centrifugal pump belongs, one must first understand the standard classification logic of the pump industry. According to the international standard ISO 5199 and GB/T 3216, pumps are classified into two major categories based on their working principles:
Dynamic Pump / Kinetic Pump
Centrifugal Pump
Axial Flow Pump
Mixed Flow Pump
Peripheral Pump
2. Positive displacement pump
Screw pump
Plunger pump
Diaphragm pump
Gear pump
Centrifugal pumps are the largest subcategory among power pumps. Approximately 80% of industrial pump applications worldwide utilize centrifugal pumps.
Centrifugal Pump vs Positive Displacement Pump: A Core Difference Comparison
| Comparison dimension | Centrifugal pump (power type) | Volumetric pump |
| Working principle | The rotation of the impeller generates centrifugal force. | Volume change forced compression |
| Flow characteristics | The flow rate decreases with the change in pressure. | The flow rate is basically constant. |
| Applicable viscosity | Low to medium viscosity (< 200 cSt) | High-viscosity fluids (with a maximum viscosity of up to 100,000 cSt) |
| Efficiency Curve | The efficient zone is narrow. The efficient zone is wide | Efficiency is stable. |
IV. Detailed Classification of Centrifugal Pumps
After understanding that centrifugal pumps belong to the category of power pumps, further exploration of their subcategories will help in making precise selections:
According to the structure of the impeller:
Closed impeller centrifugal pumps: High efficiency, suitable for clear water and low-solid content liquids
Half-open impeller centrifugal pumps: Suitable for media containing fibers or solid particles
Open impeller centrifugal pumps: Resistant to clogging, suitable for sewage treatment
According to the number of stages:
Single-stage centrifugal pumps: Head ≤ 150m, the most common working condition
Multi-stage centrifugal pumps: Head can reach over 1000m, used in high-pressure scenarios
According to the axial form:
Horizontal centrifugal pumps: Easy installation and maintenance, the largest usage
Vertical centrifugal pumps: Space-saving, suitable for deep wells, tank scenarios
According to the purpose:
Clear water centrifugal pumps: Building water supply and drainage, fire protection systems
Chemical centrifugal pumps: Corrosion-resistant materials, used in chemical processes
Waste discharge centrifugal pumps: Transportation of media containing solid particles
Shielded pumps / Magnetic pumps: No leakage sealing requirements scenarios
Five. Why are centrifugal pumps the most commonly used pump type in the industrial field?
Simple structure, high reliability: Only composed of core components such as pump body, impeller, shaft, and bearings, with low mechanical failure rate
Wide application range: Can cover water, oil, chemical liquids, and liquids with slight solid particles
Low operation and maintenance cost: Few wear parts, long maintenance cycle, high standardization of spare parts
Excellent efficiency performance: Modern efficient centrifugal pumps (in line with IEC standards) can achieve efficiency of 85% - 92%
Complete specifications: Flow range 0.1 m³/h ~ 50,000 m³/h, head range 1 m ~ 3,000 m, almost covering all industrial parameter requirements
VI. Selection Suggestions: When to Choose a Centrifugal Pump?
✅ Scenarios where a centrifugal pump is recommended:
The conveyed medium is clean water, low-viscosity liquids or emulsions.
The required flow rate is large, and the head is medium (up to 150m for a single stage).
The operating conditions are stable, and there is no need for frequent changes in flow rate.
Budget is limited, and attention is paid to cost control for procurement and maintenance.
The installation space is relatively spacious, facilitating maintenance and repair.
❌ Not suitable for centrifugal pump scenarios:
The viscosity of the medium exceeds 200 cSt (consider using a screw pump or gear pump)
Constant flow is required (the pressure can be maintained even when the outlet of the volumetric pump is blocked)
Contains large solid particles or long fibers (recommend choosing a sewage pump or volumetric pump)
Self-priming height needs to be over 5m (select a self-priming pump or volumetric pump)
