When the centrifugal pump is started, the pump shaft drives the impeller to perform high-speed rotating motion together, forcing the liquid filled in advance between the blades to rotate. Under the action of inertial centrifugal force, the liquid moves radially from the impeller to the periphery. During the movement of the liquid through the impeller, energy is obtained, the static pressure energy is increased, and the flow velocity is increased. When the liquid leaves the impeller and enters the pump casing, the flow path in the casing gradually expands and decelerates. Part of the kinetic energy is converted into static pressure energy, and then flows into the discharge pipe in a tangential direction. Therefore, the volute pump casing is not only a component that collects the liquid flowing out from the impeller, but also a energy transfer device. When the liquid is thrown from the impeller to the outer periphery, a low pressure area is formed in the impeller, and the liquid is sucked into the impeller under the effect of the total potential energy difference between the liquid level in the storage tank and the impeller. Depending on the continuous operation of the impeller, the liquid is continuously sucked in and discharged. The mechanical energy obtained by a liquid in a centrifugal pump appears as an increase in static pressure energy.

       1. It is forbidden to run without water, do not adjust the suction port to reduce the displacement, and it is forbidden to run at too low flow;

       2. Monitor the running process to completely prevent the stuffing box from leaking, and use new packing when replacing the stuffing box;

       3. Ensure that the mechanical seal has sufficient flushing water flow, and water-cooled bearings are prohibited from using excessive water flow;

       4. Do not use too much lubricant;

       5. Check at the recommended cycle. Establish operating records, including hours of operation, adjustment and replacement of packings, adding lubricants and other maintenance measures and time. The suction and discharge pressure, flow rate, input power, temperature of the washing liquid and bearings, and vibration of the centrifugal pump should be measured and recorded regularly.

       6. The host of the centrifugal pump relies on atmospheric pressure to pump water from low to high, and the atmospheric pressure can only support a water column of about 10.3m, so the host of the centrifugal pump cannot work 12 meters away from the water surface.

要求 Requirements after the centrifugal pump stops running

       1. After the centrifugal pump stops running, the inlet valve of the pump should be closed, and the valves of the auxiliary system should be closed after the pump has cooled down.

       2. The shutdown of the high-temperature pump should be performed in accordance with the provisions of the technical documents of the equipment. After the shutdown, the vehicle should be turned for half a turn every 20 to 30 minutes until the temperature of the pump body drops to 50 ° C.

       3. When the cryopump is stopped, when there are no special requirements, the pump should always be filled with liquid; the suction valve and discharge valve should be kept open; the cryopump with double-end mechanical seal, the level controller and the seal in the pump seal cavity are sealed. The fluid should maintain the grouting pressure of the pump.

       4. Pumps that transport media that are easy to crystallize, solidify, and precipitate. Stop the pump to prevent blockages, and flush the pumps and pipes with water or other media in a timely manner.

       5. Drain the liquid accumulated in the pump to prevent rust and frost cracking.