The main components of the dredging and sewage pump include the main part, control system and vacuum suction components, see the structure diagram.
1. Main part: It is composed of pump body, feed pipe and discharge pipe, and its work is suction and discharge.
2. Control system: The control system mainly uses the organic combination of air control reversing valve, travel switch, shuttle valve, ball valve and time logic reversing valve to realize the control and switching of the actuator to achieve the suction when the unit is working. The material and discharge are converted in an orderly manner;
3. Vacuum suction components: The vacuum suction components are mainly composed of Laval nozzles, negative pressure chambers and expansion tubes that are first contracted and then expanded. It is designed according to the principle of Venturi effect, including air supply port, exhaust port and vacuum port. When the gas supply pressure of the gas supply port is higher than a certain value, the nozzle ejects a supersonic jet. Due to the viscosity of the gas, the high-speed jet entrains the gas in the negative pressure cavity and makes the cavity form a higher degree of vacuum. The performance of the vacuum generator is related to many factors such as the minimum diameter of the nozzle, the shape of the shrinkage and the diffuser, the diameter and its relative position, and the size of the air source pressure. The vacuum suction component communicates with the suction port through the pump body. When the control system cyclically switches and controls the operation of the cylinder, the suction and discharge process of the unit can be completed.
The dredging and sewage pump shall be able to work normally under the following environmental conditions:
a) The suction pipe of the dredging and sewage pump shall be submerged under water and the length shall not exceed 8m.
b) The temperature of the conveying medium does not exceed 40°C.
c) Working environment temperature (0～40)℃.
d) The PH of the conveying medium is in the range of 6-8.
e) The maximum diameter of solid particles should not exceed 20mm.
f) The applicable air pressure range is 0.40MPa～0.70MPa.
Parameters
| Model of dredging sewage pump | flow | Lift | Air consumption | Working pressure | Installation dimensions |
| m³/h | m | m³/min | MPa | (Length × width × height) mm | |
| QYF25-15 | 25 | 15 | 11 | 0.5 | 1830×885×965 |
| QYF20-20 | 20 | 20 | 10.5 | 0.5 | 1830×834×915 |
| QYF17-20 | 17 | 20 | 8.5 | 0.5 | 1830×782×890 |
| QYF14-20 | 14 | 20 | 6.5 | 0.5 | 1830×782×890 |
| QYF10-20 | 10 | 20 | 6 | 0.5 | 1830×782×890 |
