How To Choose Submersible Axial Flow Pump?
May 17, 2022
With the continuous development of economy, we need more and more resources in our life, and the collection of resources has become a difficult problem, which has been solved by the emergence of pumps. Now our life is inseparable from the use of pumps, and all kinds of pumps are dazzling. In the fields of chemical industry, agriculture, mining and so on, the selection of well submersible pumps, submersible axial flow pumps, pipeline pumps, hot water deep well pumps and other pumps has become a difficult problem. A good pump can save time and effort for everyone's production. So how to buy submersible axial flow pumps? How to choose submersible axial flow pump? For this problem, let's introduce it to you by Xiaobian.
Model: QZ / qsz / QHB / QZB
Flow: 300-15000 m3 / h
Lift: 1-20m
Power: 15-450 kw
Description: QZB submersible axial flow electric pump and QHB submersible mixed flow electric pump are the updated products of traditional vertical water pump motor unit, with a design life of 20 years. Because the product is very convenient for installation, use and management, and anti-theft, it is widely used for drainage and irrigation of small and medium-sized pump stations in rural areas and towns.
1. The selection of submersible axial flow pump is based on the purpose. The submersible axial flow pump is mainly used in the drainage system of urban sewage treatment plant. Sewage treatment station in residential area. Civil air defense system and drainage system. Sewage discharge from hospitals and hotels. Municipal Engineering and construction sites. Exploration and mining auxiliary machines. Rural biogas digesters and farmland irrigation. It is especially suitable for occasions with large variation range of flow and head, which should be selected according to the purpose.
2. It is also important to purchase submersible axial flow pumps according to the site. The drainage pumps used in buildings include submerged sewage pumps, submerged sewage pumps, vertical sewage pumps and horizontal sewage pumps. Because the general site in the building is small and the drainage capacity is small, the submersible sewage pump and submersible sewage pump can be used preferentially for drainage pumps, which are generally used in important places; Vertical sewage pump and horizontal sewage pump need to install isolation foundation, self fill water and occupy a certain site, so they are rarely used in buildings.
3. According to the performance of submersible axial flow pump, the whole shell shall be made of stainless steel precision casting. The submersible axial flow pump shall have the characteristics of high speed, low noise, low vibration and low wear to prolong the service life. Equipped with overload protector, when the voltage drops, the impeller is blocked, and the water level drops below the ideal level, the temperature is too high, it will automatically cut off the power supply and stop the submersible axial flow pump. The closed impeller and shaft shall be used, which is wear-resistant and durable. Due to the special structure and mechanical position design of the impeller, the anti blocking performance is good. The submersible axial flow pump shall adopt two-way series mechanical seal. The mechanical sealing surface: the alloy is silicon carbide, the mechanical sealing rubber part: nitrile rubber, and the mechanical sealing spring: stainless steel; Durable and wear-resistant.
For example: what type of submersible axial flow pump is selected for 7000 m3 flow
This requires selection: 800 caliber submersible axial flow pump. However, the power and blade angle need to be selected in combination with the head.
When selecting the submersible axial-flow pump, we should also consider the impact of the industrial change of the submersible axial-flow pump on the medium flow, the amount of leakage and evaporation, the pressure of the suction tank and the pressure of the drainage tank. At the same time, we need to refer to the data of the pipeline system, such as the diameter and length of the pipeline, the type and number of pipeline accessories, and the geometric height of the suction tank, How to arrange the device characteristic curve in the pipeline is also very important in the design.
For the submersible axial flow pump, the chrome plated section of the pump shaft is 56mm. Generally, the stainless steel seamless steel pipe with an outer diameter of 60mm and a wall thickness of 6.5mm is selected. Shake the cut steel pipe on the lathe. At the same time, put the worn part of the submersible axial flow pump on the pump shaft 1mm larger than the inner diameter of the steel pipe, and then burn the finished stainless steel pipe red. After expansion, it is quickly sleeved on the shaft while hot. The embedded pump shaft is processed on the lathe again. In order to insert the sleeve at one time and achieve the purpose of multiple utilization, it is generally increased by 2mm on the basis of the original standard to become a small 58mm. If it is worn next time, it is processed to a small 56mm, then worn, and then processed to a medium 54mm. At the same time, the rubber bearing can increase the wear of the rubber bearing to 58 mm smaller for the first time, and continue to be used after the submersible axial flow pump. For the second time, replace the small 66 mm standard rubber bearing, and for the third time, replace it with a small 54 mm rubber bearing. This work of repairing the old and recycling the waste can make a shaft use at least four overhaul cycles, which greatly prolongs the service life of the pump shaft and saves the overhaul cost.
Submersible sewage pump has the advantages of high efficiency, compact structure, long continuous operation time and convenient installation and maintenance. It is widely used in municipal engineering, industry, hospital, construction, hotel, water conservancy construction and other industries. With the rapid promotion of submersible axial flow pump and sewage pump, the correct purchase of equipment has become the focus of users' attention.
1. Characteristics of medium: medium name, specific gravity, viscosity, corrosivity, toxicity, etc
2. Diameter and content (mass or volume percentage) of solid particles contained in the medium
3. Medium temperature: (℃)
4. Required flow
Generally, the leakage in the pipeline system can be ignored in the process flow of industrial pump, but the influence of process change on flow must be considered. If the agricultural pump adopts open channel for water transmission, leakage and evaporation must also be considered.
5. Pressure: pressure drop (head loss) in the penstock system of the suction tank pressure drainage tank
6. Pipeline system data (pipe diameter, length, type and number of pipeline accessories, geometric elevation from suction tank to pressure tank) if necessary, the device characteristic curve shall also be made. The following matters shall be paid attention to in the design and layout of pipelines:
A. Reasonably select the pipe diameter. Under the same flow, the pipe diameter is large, the liquid flow speed is small, and the resistance loss is small, but the price is high. The small pipe diameter will lead to the sharp increase of resistance loss, increase the head of the selected pump, increase the belt power, and increase the cost and operation cost. Therefore, it should be considered comprehensively from the perspective of technology and economy
B. The pressure that the discharge pipe and its pipe joint can bear shall be considered
C. The pipeline shall be arranged as a straight pipe as far as possible to minimize the accessories in the pipeline and the length of the pipeline. When it is necessary to turn, the bending radius of the elbow shall be 3 ~ 5 times the diameter of the pipeline, and the angle shall be greater than 90 ℃ as far as possible
D. The discharge side of the water pump must be equipped with valves (ball valve or stop valve, etc.) and check valves, which are used to adjust the working point of the pump. The check valve can prevent the pump from reversing and prevent the pump from being hit by water hammer when the liquid flows back (huge reverse pressure will be generated when the liquid flows back, causing damage to the pump)
Determination of flow head flow
1. If the normal flow has been given in the production process, the flow shall be considered according to the flow
2. If only the normal flow is given in the production process, a certain margin should be considered. For large flow with NS > 100, the flow margin of unintended head pump should be 5%, for small flow with NS > 50, the flow margin of high head pump should be 10%, and for pump with 50 ≤ ns ≤ 100, the flow margin should also be 5%. For pump with poor quality and poor operating conditions, the flow margin should be 10%
3. If the basic data only give weight flow, it shall be converted into volume flow
4. Submersible sewage pump flow: submersible sewage pump is a product that must be equipped and installed for industrial enterprises, municipal and other projects before the design of submersible axial flow pump. The selection must take into account the possible waterlogging of enterprises and cities caused by rainstorm and typhoon. The designed flow must ensure the occurrence of special conditions. Generally, there are main pumps and auxiliary pumps.
2. Submersible sewage pump head: the vertical height, horizontal distance, elbow and other factors must be comprehensively considered for the submersible pump head. In general, the selected submersible non clogging sewage pump should be within 20% of the required lift of the submersible axial flow pump; If it is lower than the required head, it will not be able to pump water. If it is higher than the rated head too much, the submersible pump will exceed the rated flow, and the motor will have over current, causing the machine to heat or even burn down.
5. Power supply voltage of sewage submersible pump: the motor voltage of three-phase power supply is 380V; The motor voltage of single-phase power supply is 220V. 220V single-phase sewage pump is generally used for civil electricity, 380V three-phase sewage submersible pump is generally selected for industrial enterprises, and 660V / 1140V explosion-proof type is generally selected for mining enterprises.
6. Size and mode of submersible sewage pump: the size of the submersible sewage pump body plus elbow is generally large, and the size of the sewage pit should be fully considered. If it is too small, it will cause untimely heat dissipation. There are two common installation methods of submersible axial flow pump, namely mobile installation and coupling installation. Among them, the mobile installation is relatively simple. Only hang the pump with rope and pull it into the sewage pool. The coupling installation is more complex, which can be carried out under the guidance of the manufacturer.