The starting step of the centrifugal pump should be: first open the inlet valve completely, close the outlet valve, start the motor, and wait until the speed is normal, then gradually open the outlet valve to adjust to the required working conditions.
Correct operation method of centrifugal pump
The operation of the centrifugal pump can be divided into three steps, namely start, run, and stop.
Startup: Before starting, the following preparations should be made:
(1) Check the condition of the water pump equipment.
(2) Bearing oil filling, normal oil level, and qualified oil quality
(3) Open all inlet valves of the centrifugal pump.
(4) Inject water in the pump or draw water from the vacuum pump (except for backfill) and open the air release valve to exhaust.
(5) Check the leakage of the shaft seal. It is better to use a little dripping for the packing seal.
(6) The direction of motor rotation is correct.
After the above preparations are completed, you can start the motor. After the speed is normal, check the pressure and current and pay attention to whether there is vibration and noise. After everything is normal, gradually open the outlet valve and adjust to the required working conditions. Note that the idle time of closing the valve should not exceed 3 minutes.
Operation: During operation, it is mainly a tour inspection, the inspection content has four aspects:
1. Inspection of bearings
(1) The bearing temperature does not exceed 75 ° C.
(2) No water or impurities can enter the bearing chamber, and the oil cannot be emulsified or blackened.
(3) When the rolling bearing is lubricated with thin oil, the oil level should not be lower than the centerline of the oil mark.
(4) Is there any abnormal sound? When the rolling bearing is damaged, abnormal sound will usually appear.
2. Whether the reading of vacuum gauge, pressure gauge and ammeter is normal
(1) The pointer of the vacuum gauge cannot swing too large, which may cause the pump inlet to vaporize. In addition, the vacuum gauge reading may not be too high. If the vacuum gauge is too high, the inlet valve may be blocked, stuck, or the water level of the suction tank may be reduced.
(2) The reading of the outlet pressure gauge is too low, it may be that the sealing ring and the guide vane sleeve are seriously worn. The rotor gap is too large, or the outlet valve is too open, the flow is large, and the head is low.
(3) If the ammeter reading is too large, it may be that the flow is large, or there is friction between the stator and the rotor.
3. Whether the pump unit generates large vibration, the reasons for the vibration are:
(1) The water pump and motor shafts are not aligned.
(2) The foot bolts of the water pump or motor are loose, or the foundation is not strong.
(3) The rotor mass is unbalanced.
(4) The pump runs at a small flow rate, generating radial force, backflow, and cavitation.
4. Whether the sealing work is normal
(1) There will be no dripping during the normal operation of the K-shaped power seal.
(2) If there is a cooling water device, check whether the water flow is normal.
Stop the pump
(1) If the centrifugal pump is stopped, the outlet valve should be closed first to prevent the failure of the check valve, which will cause the pressure water in the outlet pipe to be poured back into the pump, causing the impeller to reverse and cause damage to the pump.
(2) If the inertia is small when the pump is stopped, that is, the pump will stop quickly after power off, indicating that there is a mocha or eccentricity in the pump.
Conclusion: The three steps of starting, running and stopping of the centrifugal pump are very important, but the most important thing is the adjustment of the outlet valve. If it is in the suction state, the opening of the outlet valve can be relatively larger, and if it is in the backfilling state, the opening of the outlet valve can be relatively smaller. The closer the working point of the outlet valve adjustment is to the design point of the pump, the better the actual flow state and the theoretical design will be, and the pump will have high operating efficiency and save resources. Because the high-efficiency point of the pump is at or near the design point, of course, the ultimate premise is not to overload the current.
When the centrifugal pump is started, there is no water in the outlet pipe of the pump, so there is no pipeline resistance and lifting height resistance. After the pump is started, the pump head is very low and the flow rate is large. At this time, the pump motor (shaft power) The output is large (according to the pump performance curve), and it is easy to overload, which will damage the motor and circuit of the pump. Therefore, the outlet valve must be closed when starting to make the pump run normally.
The galvanized wire is made of carbon steel wire, such as Q195, Q235, AISI/SAE1045, AISI/SAE1065, etc. It is extensively used in construction, handicrafts, woven wire mesh, express way fencing mesh, packaging of products and other daily uses. The zinc coating is from 10g/sq.m to 250/sq.m. The diameter range is from 0.50 to 5.5 mm. Tensile Strength includes 350-500Mpa, 600-800Mpa, 700-900Mpa, 1100-1300Mpa, 1300-1700Mpa, etc.
Packing: 1 kg-800 kgs/ Coil lined with wax paper or pvc stripes and wrapped with hessian cloth; as customer's requirements.
Galvanized Iron Wire,Hot Dipped Galvanized Small Tie Wire, Electro Galvanized Tension Wire
DINGZHOU TIAN YILONG METAL PRODUCTS CO., LTD. , https://www.wiremeshsolution.com