SUBMERSIBLE PUMP SELECTION, INSTALLATION, MAINTENANCE AND TROUBLESHOOTING
Houses which depend on the groundwater system, they of-course needed an effective and efficient pumping system and pumping equipment. One of the pumping devices which are mostly useful for pumping out water from undercover is a
submersible pump.
However, to make the certain acceptable performance of individuals submersible pumps, it is vital that pump-set is properly selected, installed and maintained. Proper maintenance does not start with rectification or repairs or substitute of worn parts but starts right during equipment selection. Essential is a proper installation. Negligence of fundamental precaution, during installation, can lead to premature failure in the equipment. Finally, a good operation is determined by good maintenance.
1. Selection of
pump set:
A highly effective selection of submersible pumps ensures trouble-free employed by a long duration. The following criteria have to be considered for selection.
Borewell size:
As submersible pump sets are often put on bore wells, the diameter in the bore well could be the restricting aspect in selecting how large the pump-set. The most effective size borewell is six or seven-inch diameter because the pump might be placed towards the feet from the floor and glued easily.
Discharge:
The yield in the bore well is a crucial criterion for pump selection. With an overall efficient performance, the rated relieve the pump needs to be taken as 80% in the yield in the bore well. It's desirable to get a yield certificate from bore well contractor. Discharge might be around roughly for .5 hp is 5 gallons for each minute. And that means you don't have to struggle for calculations take an approximation within the list provided within the manufacturer and select the amount of water you need to fill yours over mind tank. Almost all manufactures provided the identical specs because of standard physical if adopted for design for the submersible pump.
Total Mind:
To work out the whole Mind, add static mind, attracted lower, periodic variation in level as well as the frictional losses in bends, reducers,
non-return valve, column pipe and delivery pipe. Case other terms such as the peak in the discharge outlet in the pipe because the height is directly proportional for the pressure in the liquid only at that particular position, a pressure in which the liquid to pumped the release outlet point referred to as since the mind in the pump.
Motor H.P volume of stages:
Within the pump selected above as well as the preferred mind, select the number of stages as well as the corresponding H.P/ phase within the performance chart getting maximum efficiency only at that duty point.
2. Description of submersible pump set:
Motor and pump are together referred to as pump set and they are described individually as:
The submersible pump set that's wet type possesses a motor of type squirrel cage which can be completely filled with cold, apparent water. Motors work for operating in current choice of 350 to 440 volts in three phase and 180 to 240 volts inside the situation of single phase power. Whether or not this contains thrust bearing laptop or computer can withstand axial thrust loads with minimal degeneration. A seal ring and sand guard needs to be given to safeguarding the pump in the sand as well as other foreign particles.
Pump:
Submersible pumps have a very mostly centrifugal multi-stage pump, and you'll find 2 types with regards to the needs like to find the best heads radial flow type of pump can be used along with for top discharge mixed flow type of centrifugal multi-stage pump may be used.
3. Installing Submersible pump:
Motor filling: Position of the motor needs to be stored vertically. Mostly a water filling plug is provided at the top of pump casing so it might be primed with clean, acidity free water. Water needs to be oil-free and sand free before flowing to the plug hole. Gently gradually slowly move the motor backward and forwards by leaving it for 10-15 minutes, while using plug holes open to make sure that any air bubble locked in the winding will escape. Now pour more water to losing volume introduced on through the steered obvious of air bubbles and ruin the two plugs, the motor is going to be checked completely for leakage water before it's installed. The motor is becoming ready to be from the pump and installed.
Cable Connection and Megger Test: Connect additional cable length to the plain 3-meter cable provided while using a pump.
Choosing the extra cable ought to be proper to make the certain proper functioning of a pump. Cable - section/size should match the motor power, line length and beginning system. To select the right cable diameter size we've to understand detail in regards to the nominal current in the motor, the nominal the motor as well as the supply cable total length details.
Allowing you to connect the additional cable for the pump cable, stop and strip the cable ends, to make sure that each lead joints are staggered at regular occasions. The colors in the leads which needs to grow to become part of together ought to be identical.
Insert the bottom plug and plastic tube to the pump cable and top plastic plug ought to be placed for the jointing cable. Join each lead and solder properly. Make certain that whenever jointing roughly 15 mm of intact sheathing lies within the interior in the cable splicing sleeve on the sides. After soldering file in the sharp corners around the soldering joints. insulate each joint individually by winding the rubber taps and adhesive tape tightly low of two inches within the joint.
Push the plastic tube inside the joints and make certain it's central. Cap the bottom plug and push it securely into the feet from the tube. Wind the Adhesive tape tightly across the bottom finish in the tube and plug as well as the pump cable, and press firmly to make certain a perfect seal.
suspend the joint vertically, therefore, the bottom finish in the tube points downwards. Heat the tar based compound inside a small tin and pour the molten compound inside the tube within the top finish. Refill the cavity to conquer any shrinkage and enable the compound to awesome. Slide the most effective plug lower the pump cable and push it securely into topside in the tube. Make adhesive tape and wind tightly crazy plug and tube.
To look for the insulation, conduct megger test with 500v megger, after preserving your joint in water.
4. Operation of Submersible Pump:
Turn on the power supply and verify the present indication within the voltmeter. Check if the 3 phase supply current is same or else. Otherwise, don't start the pump.
The direction of Rotation:
The direction of rotation might be altered by interchanging two phases, Greater discharge shows the best direction of rotation.
Sand Test:
Care needs to be taken before installing the pump the borewell is well flushed that it's free from sand and silt. The pump set is suitable for pumping apparent cold water with the maximum allowable sand content of 10 gms per cubic meter. A recently installed bored well, submersible pump to get started while using
gate valve round the discharge line partially opened up at the initial condition. The undercover water needs to be examined and tested for your quantity of sand content. Sand content in water show up in the glass tube, then pump set needs to be run continuously while using gate valve on discharge line is partially opened up up up to the sand content in the water involves a satisfied level. A realizing action that requires thinking about the pump should not be stopped till we observe apparent water, i.e it should not be turned off during pumping sand contained water. The greater degree of sand content could cause the premature tear and set on of pump interiors.
Shut -Lower Periods:
The pumps shouldn't be left idle for just about any week roughly since it could cause jamming of moving parts. It must be started one or more times in every single week for 5-10 minutes. This could make certain that pump set is ready for service at any preferred time.
Operation at Switch Off:
The pumps shouldn't be run more than three minutes at zero discharge since the pump could possibly get overheated due to the churning water inside the pump. Once the low discharge is required no less than one fourth from the utmost discharge ought to be allowed.
Switching Frequency:
The standstill time period of the pump between switching off and switching on again needs to be no less than a few minutes.
5. Troubleshooting submersible pump problems:
For every operation, I have to pour water inside the pipe to start motor to operate water from undercover bore well to overhead tank.
Causes and remedies:
Failure of NRV (non-return value or check value) round the discharge kind of the pump. Find out if solid particles are stuck within it, repair it if possible otherwise switch the worth. It can help to hold water inside the pump casing and suction line after the pump is switched off. This avoids the pump becoming empty for next operation. So you don't have to fill water again and again.
Maybe the level on your lawn is dropped lower, therefore, the suction lift is not achievable with the pump. The airlock will probably be created inside the suction, they are removed once we pour water
What sort of discharge pipe is suitable for a submersible pump to produce water from the bore well.
Selection
Usually GI pipe can be used discharge pipe, however, this pipe corrodes quickly due to the water and moisture inside the well.
HDPE pipe is corrosive facing the bore well atmosphere and could withstand the undercover temperatures. However, should there be essential to eliminate the motor and pump in the bore well for maintenance likely to chance of jamming? HDPE pipe may stretch with the applied pressure during remove and deform its size and shape.