The work of submersible mixed flow pump is based on the lift theory in aerodynamics, when the impeller rotates at high speed, the liquid mass in the pump body will be subject to the action of the axial lift force from the impeller, so that the water flow in the axial direction. The mixed-flow pump is a pump between the centrifugal pump and the axial flow pump, the force on the liquid mass in the pump body is both centrifugal force and axial lift, and the direction of the water flow from the impeller is oblique. Submersible axial flow pump and submersible mixed flow pump are the newer and better products of the traditional pump-motor unit. The motor driving the pump is a dry and fully enclosed submersible three-phase asynchronous motor, which can be submerged in water for a long time.

Submersible mixed flow pump and submersible mixed flow pump have incomparable advantages of traditional water pump unit.

①, because the pump and motor structure into one, without the installation site time-consuming, motor drive mechanism, the pump axis alignment assembly process, site installation is convenient, fast.

②, because the electric pump unit is submerged in water, it can greatly simplify the civil structure of the pump station. It reduces the volume of work, reduces the installation area and saves 30~40% of the project cost.

③, electric pump operation noise is low, no high temperature in the pumping station, improve the operating environment, but also can be built underground pumping station, maintain the ground environment style.

④, submersible motor dry type, using double or triple mechanical seal, F-level insulation protection grade IP68, pump section using the national unified design of water conservancy model, high efficiency, good reliability, and with the traditional pump performance with interchangeability. Convenient for users to replace the selection.

⑤, easy to operate, easy to realize remote control and automatic control.

⑥、The use of this type of electric pump is the most thorough way to solve the problem of flood control by building pumping stations in the areas along rivers and lakes where the water level rises and falls, and the long shaft and intermediate bearing between the machine and pump are eliminated, making the electric pump unit more reliable in operation.

Installation and commissioning of submersible mixed flow pump

Installation of submersible mixed flow pump.

1、According to the installation drawings, verify the size of the civil construction, and after it is accurate, the crane will install the well shaft, piece by piece from the bottom to the top. As well as the installation of the outlet, over-wall pipe, floating box pat door, pay attention to the good sealing of the flange surface.

2, the boom and electric pump unit fixed, lift the electric pump slowly down into the well shaft, the electric pump did not enter the well shaft, the cable with tying wire or tie and boom tied firmly, every 40 centimeters tied once, while tying slowly down the well, until the correct match with the sealing cone table, the boom and the crossbar fixed with a card. Lift the blind cover plate, put the cable through the sealing hole, make a good flange seal and cable seal, and complete the whole installation.

Connect the outgoing cable to the electric control cabinet in the correct order, and test the three-phase line insulation to ground with megohm meter before wiring is greater than 50 megohms. If the distance is far, terminal box can be added to facilitate testing and enter the commissioning stage.

Submersible mixed flow pump's tuned operation

First check whether the water level is within the specified range, check whether the clapper door is open and closed freely, check the three-phase power supply and voltage of the electric control cabinet, and drive and start after it is accurate. Reduced voltage start, switching time adjustment between 6s-9s, instant start to observe the voltage drop, too low will lead to starting difficulties, after starting, observe the ammeter, check whether the three-phase current is average, whether the swing is too large, whether the water is normal, whether the sound is normal; usually the electric pump running current should be in the motor rated current 80-90%. After running smoothly, adjust the overcurrent rectification to 1.1 times of the rated current, during the commissioning period, reduce the frequent starting, each start interval 15min, submersible axial start for load starting, starting current is 6 times of the rated current, frequent starting has caused the motor to overheat, so that the insulation is reduced and affect the service life.