Axial pump performance characteristics is what? Use, should pay attention to what issues? Axial flow pump shape and working principle of centrifugal pumps are different, its performance is also very different. In practice, we must strictly distinguish between the use of different methods to guide the production practice to solve production problems. Axial flow pump performance parameters used to represent. Flow, lift, power, efficiency and other parameters have a certain relationship between each other, if the relationship between the parameters used to represent the curve, is the pump performance curve, the curve is the pump plant experimental methods, to provide users with technical information. Flow and lift, flow and power changes between the law is the same. In general, the head and power decreases gradually with the increase of pump flow, but there is a turning point in the process of change. With the increase of flow rate, the head and power gradually increase but then gradually decrease. When the flow rate is high, the efficiency is the highest. When the flow rate Q = 0, the pump lift and shaft power are all about 1.5-2 times of the highest efficiency. Axial flow pump in the case of small flow, because the pump swirl, the formation of a sharp drop in pump efficiency, and performance instability will appear in the working state, is not allowed in the production. From the axial flow pump performance parameters of the relationship between the law of change tells us: 1. Axial flow pump can not easily reduce the flow, otherwise, the pump will be unstable working conditions, and produce severe vibration and noise, efficiency also dropped sharply This is very bad for pump work. 2. In order to reduce power starter power, axial pump should be opened valve, because at this time the minimum power, the most safe power machine. Otherwise, the motor starting power is too large, resulting in burning motor. 3. Axial flow pump should not be used to adjust the variable valve performance of the pump. In summary, axial-flow pumps are characterized by high-flow, low-lift agricultural pumps. Axial pump in use, how to adjust its performance? Axial flow pump in use, and sometimes pump performance does not meet production needs, we must adjust the pump performance, so that it can meet the actual needs. For example, the winter dry season, summer flood season, into the pool or the pool water level has changed, that is, the actual terrain Pumped water height has changed, the original head and flow has been determined to not meet, lower efficiency, the pump is not operating. Therefore, to meet the new requirements of the water pump, but also to work under higher efficiency, which requires the performance of the pump to adjust. Axial flow pump performance adjustment, usually using two methods: 1. Variable speed regulation We already know that axial flow pump is working at a certain speed, and access to the appropriate flow, lift, power and efficiency. When the speed changes, its performance parameters also change accordingly, so as to achieve the purpose of regulation. If the axial flow pump is powered by a diesel engine or a gasoline engine, the throttle speed can be changed by changing the throttle size. If the axial flow pump is connected with the power machine through a V-belt or flat belt indirect transmission device, the diameter of the transmission pulley can be changed to change speed Drive wheel or driven wheel can, the purpose is to change the transmission ratio. Variable speed pump performance, more economical, the scope of application is broader, all agricultural pumps can be used. 2. Variable angle adjustment From the structure point of view, axial pump impeller with a huge hub for easy installation of adjustable angle blades. When the blade installation angle is changed, the blade lift on the water also changed, thus changing the pump performance, which is the axial pump variable angle adjustment. As the blade mounting angle increases and decreases, the axial flow pump flow, lift, power that is changed, however, the highest point of efficiency but no change, it is very conducive to the axial flow pump performance regulation. According to the structure of the impeller, the blade installation angle of the device, the leaves are divided into three types: (1) the fixed blade leaves and wheel cast as a whole, blade installation angle has been fixed in the design and manufacture, can not be adjusted during use . This type of impeller used for small pumps. (2) Semi-adjusting vanes Loosen the fixing nut and set screw of each vane on the impeller hub. Adjust the vane mounting angle according to the requirements and fasten it. General blade mounting angle from the negative 100-180. In this range, according to the requirements to adjust. (3) Leaf-blade leaves with special design of the angle adjustment mechanism to adjust, you do not have to disassemble the impeller, you can directly manipulate the mechanism to change the blade mounting angle, the adjustment range from 0-260. Blade angle adjustment mechanism has two kinds of mechanical adjustment and hydraulic adjustment. This impeller is mostly used for large-scale axial flow pump. Axial pump operation, the pump is not water or water reduce the reason why? How to troubleshoot? Axial pump operation more reliable. However, there are times when problems can occur. Failure, it should be ruled out promptly. Axial pump operation, the pump does not water. Reason for the failure: Remedy: Impeller submerged depth is not enough 1. Lower the pump installation height 2. Pump rotation direction is not 2. Adjust the pump rotation direction 3. Pump speed is too low 3. Change the transmission speed ratio, increase pump speed 4. Impeller and blade Between the rupture or blade fixed 4. reinstall the impeller, tighten the nut, or replace the impeller nut loose, leaves move around 5. leaves a lot of debris around the backwash red mixed several times, still no water, you need Remove the pump to the miscellaneous axial flow pump in operation, reduce the amount of water. Reason for the failure: Remedy: blade outer wear or blade crushing partially 1. Replacement of the impeller lift is too high 2. Adjust the lift, check the water outlet pipe plug phenomenon is not enough depth of the impeller 3. To reduce the impeller installation height The pump speed is less than required 4. Replace the drive pulley to improve the pump speed around the weeds and debris on the leaves 5. Shutdown backwater several red hybrid, plus the trash in the sink mouth To prevent failure, should pay attention to the operation: Attention to changes in the instrument ; Attention to the sound and vibration of the unit pay attention to changes in the water level into the pool, such as into the pool water level down to the minimum level below the prescribed time, should be shut down; pay attention to the cleanliness of the pool, such as the pool of weeds and debris, it should be promptly Picked up Small mobile axial flow pump in what occasions apply? What are the characteristics? In promoting the use of what should pay attention to? Axial flow pumps are generally used for fixed pumping operations, which control irrigation and drainage area is relatively large. In recent years, with the reform of rural production system and the rapid development of aquaculture, a small mobile axial-flow pump has been widely used. Although this pump head is low, but the flow is quite large, and the supporting power is small, stable performance, reliable work, simple structure, small size, light weight, installation and transfer is extremely simple and can be used for small-scale irrigation or drainage ponds, Can also be used for water supply and drainage of other water conservancy projects or construction sites. Small mobile axial flow pump developed by Agricultural Machinery Factory in our province has been formulated as one of series of agricultural water pump with specifications of 4, 6, 8, 10 and 12 inches. Its structural features are as follows: Supporting power are optional vertical motor, coupling direct drive, where in the field erected a place where the grid can be used. Installation form for the mobile vertical, easy to use. In operation, the fault is less. Single-stage impeller, fixed blade, blade number 4. Under the water tube generally installed under the bracket or grating. Pumps, motors, transmissions, and inlet and outlet pipes are all unitary, so the pump is compact. In the promotion of use, should pay attention to the matter: This small pump, flexible, suitable for mobile pumping operations. Generally do not set up pump room, placed in the field pumping, sun and rain, the motor is easy to damp, Moreover, the connection of the motor wire, most of the temporary cable. Therefore, in promoting the use, should pay special attention to electricity safety, so as to avoid electric shock accident. The pump head must be calibrated on the nameplate to use the value, can not arbitrarily increase the outlet pipe, otherwise there may be overloaded. Pump erection, diagonal work can be, when used obliquely, its head to a vertical height meter. Long-term use of the pump, the pump body to be placed upright, and pay attention to motor moisture.
