What should you do when you encounter some annoying pump problems? On the one hand, the choice of large brand stainless steel gear pumps can reduce the incidence of failure to a certain extent; On the other hand, some small failures in the process of use, in fact, 80% can be solved by themselves, as long as you master some quick elimination methods, that is, you can eliminate many unpleasant small obstacles, save worry and effort.
Common faults of pump and motor are sorted out for you.
In practice to deal with the fault, because according to the specific problems, the actual analysis, should comply with the principle of the first outside after the inside, do not operate blindly.
First of all: should check the power supply situation: whether the connection is reliable; Whether the switch contact is careful; Whether the fuse is blown; Whether the three - phase power supply is equal. If there is a circuit break, bad contact, fuse blown, lack of phase, should find out the reason and repair in time. Second: check whether it is a mechanical failure of the pump itself.
* fault one, the water pump can not start
Common reasons: packing is too tight or between the impeller and the pump body is blocked by debris accumulation; Pump shaft, bearing, leakage reduction ring rust; The pump shaft is seriously bent.If you have an air source, it is recommended to use diaphragm pump AODD or EODD, which has a long service life and is widely used. High viscosity liquids can also be transferred.
Elimination method: relax the packing, dredge the drainage tank; Disassemble the pump body to remove debris and rust; Remove the pump shaft to correct or replace the new pump shaft.
* fault two, insufficient flow
Causes: mostly suction pipe leakage, bottom valve leakage; Water intake blockage; The water depth of the bottom valve is insufficient; Pump speed is too low; Excessive wear of sealing ring or impeller; Water absorption height exceed the standard, etc.If you are using a plastic centrifugal pump, check the impeller for wear and the fluid for particles.
Exclusion method: check the suction pipe and the bottom valve, block the leakage air source; Clean up the silt or blockage at the intake; The depth of the bottom valve into the water must be greater than 1.5 times the diameter of the inlet pipe, increase the depth of the bottom valve into the water; Check the power supply voltage, improve the pump speed, replace the sealing ring or impeller; Lower the installation position of the pump, or replace the high head pump.
* fault three, not suction water
Causes: there is air in the pump body or gas accumulation in the intake pipe, or the bottom valve is not closed tightly, the filling water is not satisfied, the vacuum pump packing is leaking badly, the gate valve or the shutter is not tight.Please note : Gear bitumen Transfer Pump con't transfer water，Gears tend to wear out if water is diverted.
Elimination method: 1. First put the water pressure, and then the pump body filled with water, and then boot. At the same time, check whether the check valve is tight, and whether the pipeline and joint have air leakage. If there is air leakage, apply lubricating oil or blending paint at the joint after disassembly, and tighten the screws. 2. Check the oil seal ring of the pump shaft, and replace it with a new one if it is seriously worn. 3. Pipeline leakage or air leakage. Nuts may not be screwed tightly during installation. If the leakage is not serious, cement can be daubed in the place of leakage or leakage, or cement slurry mixed with asphalt oil. For temporary repairs, apply mud or soft soap. If the joint is leaking, the wrench can be used to tighten the nut, if the leakage is serious, it must be disassembled again, replace the cracked pipe; Lower the head and press the nozzle of the pump into the water by 0.5m.
* fault four, the water pump does not water
Causes: pump body and suction pipe is not filled with water diversion; Dynamic water level below the pump filter pipe; The suction pipe is broken.
Elimination method: eliminate the bottom valve fault, filled with water; Lower the installation position of the water pump so that the filter pipe is below the moving water level or the filter pipe is pumped up at the same moving water level; Repair or replace the suction pipe.
* fault five, the pump body violent vibration or noise
Causes: the pump is not installed firmly or the pump is installed too high; Motor ball bearing damage; The pump spindle is bent or different from the motor spindle, not parallel, etc.
Treatment method: stabilize the water pump or reduce the installation height of the water pump; Replace the motor ball bearing; Correct the bending of the pump spindle or adjust the relative position of the pump and the motor.
* fault six, power consumption is too large
Cause: pump speed is too high; The pump spindle is bent or the pump spindle is different from the motor spindle or is not parallel; Selection of pump head is not appropriate; Pump suction sediment or blockage; Motor ball bearing damage, etc.
Treatment method: check the circuit voltage, reduce the pump speed; Correct the main shaft of the pump or adjust the relative position of the pump and the motor; Choose suitable head pump; Clearing sediment or blockage; Replace the motor ball bearing.
* Fault Seven, drive shaft or motor bearing overheating
Cause: lack of lubricating oil or bearing rupture, etc.
Treatment method: add lubricating oil or replace bearing.
These are the common causes of the pump "failure", not all the reasons, in practice to deal with the failure, but also because according to the specific problems, the actual analysis, should comply with the principle of the first after the inside, do not operate blindly.Most of the time, the bearing is damaged, perhaps jaw couplings or pin bush coupling are not in the same horizontal line.
Before the analysis of pump failure, we must also learn to use the multimeter and megohmmeter, the use of notes are:
1, if it is impossible to estimate the size of the measured voltage or current in advance, it should first dial to the highest range to measure once, and then gradually reduce the range to the appropriate position according to the situation. After measurement, switch the range to the highest voltage and turn off the power supply.
- When measuring the voltage, the digital multimeter should be in parallel with the circuit under test; When measuring current, it should be in series with the circuit to be measured. When measuring direct flow, it is not necessary to consider positive and negative polarity.
- When the AC voltage block is misused to measure the DC voltage, or when the DC voltage block is misused to measure the AC voltage, the display screen will display "000", or the number on the low position will jump.
- It is forbidden to change the range when measuring high voltage (more than 220V) or large current (more than 0.5A), in order to prevent arc generation and burn the switch contact.
- When "BATT" or "Low BAT" is displayed, it means that the battery voltage is lower than the working voltage.
Problem 1: The motor overload when the pump works
General motors have a rated operating power, called the rated power, in watts (W) or kilowatts (kW). Under some circumstances, the actual running power of the motor exceeds the matching rated power of the water pump, then this situation is called motor overload. The motor has the following manifestations:
Motor heat is too large;
The motor speed drops, or even drops to zero speed, showing that the motor does not rotate;
The motor has a low buzzing sound, accompanied by a large vibration;
When the motor load changes dramatically, the motor speed will fluctuate between high and low.
Problem two: the three-phase motor is missing when the pump is running
The three-phase motor must be driven by three cables in operation to achieve three-phase balanced operation; If the power supply is provided by two power lines, it can also run, but the longer running time will cause the motor to burn out due to lack of phase. Method of identifying motor phase loss:
Use a multimeter to measure the voltage of three power lines, whether there is no voltage drop in one phase;
Check the copper wire in the three power cables, whether two of them are black, and the copper wire of one power cable is not black and remains the same as before;
Open the motor cavity, in general, two phases of the three-phase motor will burn out, the other phase remains the same.
Problem 3: The water pump motor suddenly tripped
If the matching power protector and the pump motor is consistent, under normal circumstances, the protector will not trip. The main reasons for the tripping of the protector are:
Pump motor overload;
Pump motor temperature rise is too high;
Pump motor running current is too large;
The supply voltage of the water pump is too high.
Causes and solutions of the problem:
Question 4: The water pump motor has been flooded
In general, the pump motor is not allowed to enter the water (the exception of the water pump). There are several cases of motor inlet water:
Waterproof cable damaged water;
The water pump motor power line is not sealed well;
The sealing structure of the inlet line of the pump motor is damaged and enters water;
Mechanical seal damage water pump;
Water pump O-type sealing ring damage;
The bolt at the sealing place is not tightened, resulting in water intake of the motor;
The parts of the pump are damaged and seeping.
Causes and solutions of the problem:
Problem 5: There is leakage in the pump motor
In general, the pump motor is not leakage, but in the following circumstances, the electricity will leak:
Waterproof cable damage leakage;
Water pump motor power line wiring is not sealed well leakage;
Water pump motor leakage;
Leakage after the pump motor is burned out;
Too low insulation resistance leads to leakage.
In order to ensure the personal and property safety of the pump in the case of motor leakage, it is necessary to correctly install the ground of the pump, and it is best to install the leakage switch at the same time.
Question 6: The gear pump and motor cannot start
The pump electric machine does not start (does not rotate or the speed is too low) generally from the following reasons:
Water pump leakage;
The supporting power supply voltage is too low;
Pump gear due to foreign body stuck;
Bearing damage stuck;
Motor overload operation (overload);
Three-phase gear pump three-phase power supply reverse connection;
Phase loss of three-phase motor;
Electrical scavenging;
Capacitor damaged, reverse connection, low capacity.
