What is the structure of the middle pump? The suction inlet and outlet of the single-stage pump are under the pump axis, and the horizontal direction and the axis are in a vertical position and the pump shell. In the middle, there is no need to disassemble the water inlet during maintenance, the discharge pipe and the motor (or other prime mover) look from the coupling to the direction of the pump, the pump is rotated in the direction of the reverse inch needle, such as according to the special order needs of users can also be changed to the clockwise inch needle rotation. The main components of the single stage pump are: pump body, pump cover, impeller, shaft, double suction sealing ring, shaft sleeve, bearing and so on. In addition to the use of high-quality carbon steel shaft, the rest of the cast iron. The pump body and the pump cover constitute the workshop of the impeller, and the inlet and outlet water flange is provided with a pipe screw hole for installing the vacuum gauge and pressure gauge, and the lower part of the inlet and outlet water flange is provided with a drain pipe screw hole.

After static balance check, the impeller is fixed by the sleeve and the sleeve nuts on both sides, and its axial position can be adjusted by the sleeve nuts. The axial force of the impeller is balanced by the symmetrical arrangement of its blades, and part of the residual axial force may be borne by the bearings at the coaxial end.

The shaft of the medium-open pump is supported by two single-row radial ball bearings, which are mounted in bearings at both ends of the pump body and lubricated with butter. The double suction seal rings are used to reduce the leakage of water from the pump pressure chamber back into the suction chamber.

The pump coupling of the middle open pump is driven directly by the motor. The shaft is sealed with soft packing, in order to cool and lubricate the sealing cavity and prevent air leakage into the pump, there is a water seal ring between the packing. When the pump is working, a small amount of high pressure water flows into the packing cavity through the water seal tube and plays the role of water seal.

How to install the middle pump?

1. Start and stop: Before starting, rotate the rotor of the pump, the rotor should be smooth, close the outlet gate valve, and inject water into the pump (if there is no bottom valve, evacuate the water with a vacuum pump) to ensure that the pump is filled with water and no air. If the pump is equipped with a vacuum gauge or pressure gauge, turn off the rotary motor connected to the pump and restart it until the speed is normal. Then gradually open the outlet gate valve. If the flow is too large, the small gate valve can be adjusted appropriately. Otherwise, if the flow rate is too small, please raise the gate valve and evenly tighten the compression nut on the packing gland to make the liquid drip out. At the same time, pay attention to the temperature rise of the packing chamber. Stop the pump operation, first close the plug of the vacuum gauge, pressure gauge and the gate valve on the outlet pipe, and then close the motor power supply, such as when the ambient temperature is low, should open and remove the square plug in the lower part of the pump body to avoid freezing and rupture, stop using for a long time, disassemble the pump, dry the other part of the water. Apply anti-rust oil to the machined surface and keep it safe.

2. Operation: The limit high temperature of the pump bearing should not exceed 75°C, the amount of calcium-based butter used for lubricating the bearing should account for 1/3~1/2 of the bearing space, due to the wear of the filler, the filler gland can be properly pressed, if the wear is too much, it should be replaced, regularly check the shaft components, pay attention to the temperature rise of the motor bearing, during operation, such as noise or other abnormal sounds, Should stop immediately, check the cause and rule out. Do not arbitrarily increase the speed of the pump. However, the rotation speed can be reduced. For example, the rated speed of this pump is N, the flow rate is Q, the head is H, the shaft power is N, the converted speed is n1, the flow rate, the head and the shaft power are Q1, H1 and N1 respectively.