Learn - Sep. 19, 2022
Axial flow pump is a kind of high specific speed (more than 500) pump type, characterized by large flow rate, low head, large diameter, suitable for drainage irrigation, material for cast iron, famous for cast iron large diameter drainage axial flow pump. Axial flow pump has the characteristics of large capacity and low head, widely used in low-lying river network area of large area drainage and large flow and low head water transfer project.
In the professional hydropower engineering or Agricultural Water Conservancy Engineering, agricultural drainage irrigation engineering, the drainage axial flow pump according to the installation direction of the pump shaft is divided into Vertical Axial Flow Pump, Diagonal Axial Flow Pump and Horizontal Axial Flow Pump three types, the installation direction of the pump shaft is different, resulting in the hydraulic performance of the axial flow pump, installation and maintenance, engineering cost and adaptation conditions and other aspects of the change.
Can you tell the difference between vertical axial flow pump, diagonal flow pump and horizontal axial flow pump?
After reading the following paragraphs, you will know the answers.
Vertical Axial Flow Pump Diagonal Axial Flow Pump Horizontal Axial Flow Pump
A traditional commonly used pump type, is also the most used in continental agricultural countries a type of pump, used for river diversion, often called Drainage Axial Flow Pump, Agricultural Irrigation Axial Flow Pump. Vertical axial flow pump is the pump body is arranged in the pump layer, the motor and transmission part is arranged in the motor layer, the motor is connected with the vertical axial flow pump by a proprietary drive shaft. Usually, for the motor, the transmission part, the weight of the pump rotor and the axial force of the vertical axial flow pump are borne by the motor layer, while the vertical axial flow pump only bears the weight of the pump shell components and some other external forces during operation. Vertical axial flow pump wet chamber (open) and dry chamber (closed), the main difference is whether the vertical axial flow pump is completely placed in the liquid.
The characteristics of vertical axial flow pump are: the plane size is small, the workshop covers an area of small, the impeller of vertical axial flow pump is submerged in water, and the vertical axial flow pump is convenient to start; The motor can be installed in the upper part of the vertical axial flow pump, can be located above the highest flood level, ventilation, lighting and moisture-proof conditions are good. On the other hand, such installation method requires the height of the whole unit of vertical axial flow pump, the building where the pump group is placed is high, the foundation excavation is deep, and the foundation bearing capacity is concentrated. The installation environment of pump base has high requirements and the maintenance situation is complex. The installation environment of the vertical axial flow pump base has high requirements, and the maintenance situation is slightly complicated.
Taking an agricultural drainage and irrigation project as an example, the project started in 2014 and is located in a city in the southern plain of China. Four pump stations are constructed. Vertical axial flow pumps, diagonal flow pump, horizontal axial flow pump in this project have played the appropriate benefits of the application. Station A is located on the right bank of the main river bed in the city, with the river bottom elevation 11m and the pump house floor elevation 7. 51 m, the foundation excavation elevation is 6m, the maximum excavation depth is 5m. Pump station design water level 14. 5m, the lowest operating water level 13. 7 m, the highest operating water level 17. 5 m, the variation of water level of the pump is 3. 8 m. After comparison and selection in the design, the unit is selected as a vertical axial flow pump.
Inclined type axial flow pump has a vertical axial flow pump under low head does not have the advantages of axial flow pump in and out of the water flow condition of smooth fluent, not only can improve the efficiency of axial flow pump device, but also has less excavation, foundation stress is relatively uniform, axial flow pump and motor connection, the diaphragm coupling deformation range is bigger, can effectively compensate the error caused by the installation and foundation displacement with; The shell of diagonal axial flow pump adopts the form of splitting, which can directly lift the upper shell, convenient installation, repair and maintenance.
In this agricultural drainage and irrigation project, Station B is located on the east bank of the river in the urban area, and 6 diagonal axial flow pumps with an Angle of 30° are installed. Angle of 30° diagonal axial flow pump and Angle of 15° diagonal axial flow pump compared, Angle of 30° diagonal axial flow pump has 5 advantages: ① The flow is smooth when the axial flow pump is running, the efficiency can reach more than 65%, than Angle of 15° diagonal axial flow pump is 12% higher; ② Convenient installation and maintenance, emergency repair diagonal axial flow pump, can save half of the engineering quantity; ③ The foundation excavation of the building where the pump group is placed is significantly reduced. Take the diagonal axial flow pump with 1.8m impeller as an example, during construction, the excavation of earth and rock is reduced by 14%, the backfilling is reduced by 10%, and the inlet flow channel is raised, which reduces the siltation during operation. ④ Foundation stress becomes more uniform, and the coefficient of foundation inhomogeneity can be changed from 1. 80 down to 1. 09; ⑤ The junction box of the motor can be placed between the piers of the motor, without the need to arrange the location of the junction box.
Station C is located at the confluence of two rivers. The practice of engineering construction and operation shows that diagonal axial flow pump is also adopted.
The design head of the horizontal axial flow pump is within the range of 0 ~ 7.5m, the installation and maintenance of the axial flow pump is convenient, the axial flow pump and the motor are arranged horizontally, the load distribution of the pump group is more uniform, the foundation excavation of the pump group is less, and it is suitable for the pump station with weak foundation stress. On the other hand, it will cause the whole pump group room covers a large area, the efficiency of the axial flow pump can not be significantly improved.
Station D is located at the outlet of the flood control section of a river. The lowest operating water level of the inlet of the pump station is 1.0m, and the highest operating water level of the inlet of the pump station is 2. 2m, the design water level is 1. 50 m. The water level of the inlet has little variation, and the foundation is silt soil, which is difficult to excavate. The horizontal drainage axial flow pump is adopted, and the foundation stress is 80. 00 kPa, the foundation is treated with powder spraying pile to meet the load bearing requirements of the pump station foundation.
Statistical Table of Basic Situation of Pump Station
| Station Name | Design Head (m) | Design Flow Rate (m3/s) | Number (set × kW) | Building Size Length×Width×Height （m×m×m） | Pump Model | Foundation Feature | Pump Installation Scheme |
| A | 4.40 + 1.20 | 46． 60 | 4×1000 | 32×17×29 | 1800ZLB1166-3.38 | pebble bed | Vertical |
| B | 3.24 + 0.92 | 70． 20 | 4×800 | 39×17×22 | 1700ZXB11． 5 － 4． 16 | Coarse sand | Angle 30° |
| C | 0.81 + 1.17 | 139． 30 | 6×1000 | 52×21×21 | 2400ZXB － 2． 50 | Red sandstone | Angle 15° |
| D | 0.90 + 0.65 | 22． 50 | 3×250 | 32×17×15 | 1600ZW7． 5 － 1． 20 | Muddy soil | Horizontal |
Axial Flow Pump Summary
Modern agricultural water conservancy uses a large number of drainage irrigation axial flow pump, according to the specific situation to choose the appropriate vertical axial flow pump, or diagonal flow pump, or horizontal axial flow pump, can achieve high efficiency, low cost input, good operation of agricultural irrigation pump group, to achieve ECO- friendly green agriculture. We have been specialized in manufacturing axial flow pumps for 70 years. Thousands of cast iron axial flow pumps for drainage and irrigation have been installed in the world. Experienced engineers and technicians can choose the most appropriate pump for your drainage and irrigation pump group, professionally customize various sizes of drainage and irrigation agricultural axial flow pumps, and guide installation, testing and maintenance.
