Figure 1: Stainless steel water pump.
1.Check whether the water pump motor is in good condition.
2.Good airtightness should be ensured between water pump and pipeline. Particularly when the water pump is used to pump water, it must be ensured that there is no air leakage, and the device has no possibility of trapping air. The weight of the inlet and outlet pipelines shall not be added to the flange of the water pump.
3.After the water pump is leveled, concrete shall be poured between the pump and the foundation. For the water pump unit with shock absorber, the intermediate isolator can be moved to adjust the level of the unit.
4.Sluice valve and check valve are usually installed between water pump and outlet pipe. The sequence is pump outlet—gate valve—check valve—water outlet pipeline.
Figure 2: Water pump control valve.
If the geographical environment permits, the water pump shall be as close to the water source as possible to reduce the length of the suction pipe. The foundation at the pump installation site shall be firm, and a special foundation shall be built for the fixed pump station.
The water inlet pipe shall be reliably sealed, and must have a special support, not being hung on the water pump. For the water inlet pipe with bottom valve, the axis of the bottom valve shall be installed as perpendicular to the horizontal plane as possible, and the included angle between the axis and the horizontal plane shall not be less than 45 degrees. When the water source is a channel, the bottom valve shall be more than 0.50m higher than the bottom of the water, and net shall be added to prevent junks from entering the pump.
The machine and pump base shall be leveled and firmly connected with the foundation. When the machine and pump are driven by belt, the tight edge of the belt is at the bottom, so the transmission efficiency is high. The rotation direction of the water pump impeller should be consistent with the direction indicated by the arrow; when coupling transmission is adopted, the machine and pump must be coaxial.
Figure 3: The installation of submersible sewage pump.
The installation position of the water pump shall meet the requirements of allowable maximum vacuum suction height. The foundation must be horizontal and stable to ensure that the rotation direction of the power machinery is consistent with that of the water pump.
If there are a multitude of machine units in the same machine room, there should be a distance of more than 800 meters between units and between units and walls.
Suction pipe of water pump must be sealed well, and elbows and sluice valves shall be minimized. The suction pipe of the water pump must be well sealed, and elbows and gate valves shall be minimized. Air shall be exhausted during filling and water diversion. There shall be no air accumulated in the pipe during operation. The suction pipe is required to be slightly upward inclined to connect with the water inlet of the water pump, and the water inlet shall have a certain submergence depth.
1.Check that the pump body is free of damage, intact in the nameplate, clear in the direction of water flow, clean in the appearance and intact in the paint.
2.Check whether there is leakage. If there is water leakage, please ensure immediate repair.
3.Replenish lubricant, and replace it if the quality of oil changes and has impurities.
4.Replace them if coupling screws and rubber washers of the coupling are damaged.
5.Tighten the base screws and take anti-rust measures.
6.Maintain flexible rotation and ensure the pump shaft and motor shaft are on the same center line.
Figure 4: Centrifugal pumps Installed at the wall corner.
1.The valve door can be opened and closed flexibly without jamming, and closed tightly without water leakage inside and outside.
2.The one-way valve can be operated flexibly without water leakage.
3.The appearance of pipes and accessories shall be clean and beautiful without cracks, and the paint shall be intact without falling off.
4.The needle of the pressure gauge is flexible, is accurate in indication, is clear in dial, is easy to observe, is good in fastening, and the gauge valve and joint are free of water seepage.
1.Ensure clean appearance, clear nameplate, all parts are fastened, the coupling is provided with a protective cover, and the ground wire is well connected.
2.Disassemble the wire connecting strips in the motor junction box, and use a 500V megger to telemeter the insulation resistance between phase and phase, phase to ground of the motor winding, which shall not be less than 0 5MQ。
3.Ensure three-phase conducting wires and connecting pieces in motor junction box are tightly connected, with no signs of heating and discoloration, and indications are clear. The external connecting wire does not move or hinder the operation.
Figure 5: Water pump control cabinet.
1.Disconnect the main power supply of the control cabinet, check each changeover switch, and keep the start and stop buttons flexible and reliable.
2.Check whether the air switch, contactor, relay and other electrical equipment in the control panel are in good condition, and tighten the wiring screws of the contact wire head and connecting terminal of each electrical equipment.
3.Clean the inside and outside of control panel and ensure no dust.
1.Close the automatic air switch in the control panel, turn on the power supply of the control circuit, and check that the power indication is normal.
2.Ensure flexible rotation after manual driving.
3.Start water pump and observe whether the steering, starting current and electrical action are in normal sequence.
4.Observe that the water pump operates stably without obvious vibration and abnormal sound, the pressure gauge indicates normally, each electrical equipment in the control panel has no abnormal noise, and the three-phase current imbalance is less than 20%.