We have dig the borewell for 900 feet, got water around 420 feet and 700 feet while digging. after put the motor (15HP Taxmo), its not giving continues water, its giving water for 2minute then stops for 40sec… What to do to get continues water ?
Looks like a yield issue here.
I would suggest you for a draw down test or V notch and identify the exact bore yield in LPM - Lets call this X
Select a suitable motor and pump that would pump Y LPM at a preferred head and ensure that Y is < X.In your case lower your pump further till as per Texmo’s performance chart so that Y is less than X.
Also, PFA a file from Indiawaterportal.org on hydrofracturing.
Also,For improving the output in the bore-well, go for water harvesting technique. At a distance of five to six feet from your bore-well dig a pit of three to four feet in depth with a dimension of 3 feet by 3 feet length and breadth (square). Pour a layer of sand at the base of the pit, followed by a layer of small size concrete and again a layer of sand over the concrete, thus filling the pit with alternate layers of sand and concrete. During the rainy reason, the rain water gets filtered in the pit before entering the bore-well.
Hope this helps you!
HYDROFRACTURING.pdf (878 KB)
please note concrete as stone jelly. As concrete will not allow water to pass.
Even you can fill the pit with big stones of 1 feet or so and then every layer smaller than the earlier one and final with sand. You have to make all/part the water from your land to fill the pit and make arrangements for extra water to flow out of the pit.
In your case, you have got two potential yield Points at the depths of 420 feets & 700 feets, and as informed by you, the pump runs for 2 minutes at every 40 secs, considering your pumping pattern, we can assume the following scenarios for not getting continuous flow of water -
Scenario - I - Optimal Development of Yield Points NOT DONE by cleaning & Flushing of the Borewell after completion of drilling -
The borewell is drilled by the DTH (Down The Hole) method, In DTH drilling the percussion mechanism – commonly called the hammer – is located directly behind the drill bit. The drill pipes transmit the necessary feed force and rotation to hammer and bit plus compressed air or fluids for the hammer and flushing of cuttings. The fast hammer action breaks hard rock into small flakes and dust and is blown clear by the air exhaust from the DTH hammer, in this process, due to higher ROP (Rate Of Penetration) the borewell with the mediocre yield may end up giving no yield due to the cementation caused due the dust & water (Influxes) on the wall of the borewell.
Therefore, to get the water yield available in the borewell, we have to maintain the Annular Velocity of minimum 3000ft/min for cleaning of the borewell & 5000ft/min for the optimum cleaning of the borewell, by introducing the appropriate amount of Drilling Fluid (Water) to avoid the influxes in the annulus that may restrict the bore hole cleaning with continued Air drilling in the presence of water.
Solutions to Scenario - I -
a. Pump Purging -
The pump purging is done to flush the borewell with liquid, you need to make a of soapy liquid by mixing SURF detergent powder in 02 No.s of Barrel filled with water (SURF powder must be mixed in proportion to make water soapy, where in the fingers slip with soapy water).
Pour the soapy water into the borewell & recycle the water within the borewell.
Sp. Note - DO NOT discharge the water out from the borewell for at least 24 hours
During this process, due to the pressure of the Pump & because of the agitation created by the water movement within the borewell, along with the special chemical properties of the SURF detergent powder the influxes in the borewell shall be cured and the free flow of water from the aquifer (Yield Points) shall be available for getting the actual yield from the borewell.
Scenario - II - Improper Pumpset Selection, Changes required in Pumping Pattern, Automization system etc -
A proper selection of submersible pumpset ensures trouble free working for a longer duration. The following criteria have to be considered for selection.
Bore well size:
As submersible pump sets are normally installed on bore wells, the diameter of the bore well is the restricting factor in selecting the size of the pump-set. The best size of borewell be 6 to 7 inch diameter because the pump can be inserted to the bottom of the ground and fixed easily.
The yield of the bore well is an important criteria for pump selection. For an overall efficient performance, the rated discharge of the pump should be taken as 80% of the yield of the bore well. It is desirable to obtain a yield certificate from bore well contractor. So you no need to struggle for calculations just take an approximation from the list provided from the manufacture and select the amount of water you need to fill your over head tank. Almost all manufactures provided the same specification because of standard physical if followed for the design of submersible pump.
To workout the total Head, add static head, drawn down, seasonal variation in water level and the frictional losses in bends, reducers, non return valve, column pipe and delivery pipe. This is simply other terms which include the height of the discharge outlet of the pipe, because the height is directly proportional to the pressure of liquid at that particular position, the pressure at which the liquid to pumped out the discharge outlet point is termed as the head of the pump.
Motor H.P number of stages:
From the pump selected above and the desired head, select the number of stages and the corresponding H.P/ phase from the performance chart having maximum efficiency at that duty point.
As per your pumping pattern, I shall consider that the Pump has been installed at any depth below 750 feets, you had mentioned 15 HP Texmo Submersible Pumpset, as per the depth of the borewell mentioned by you the Pumpset Installed by you shall be -
Make - TEXMO
Model No. - RS40/26-30
Horse Pwr -15
Stages - 26-30
Head Range = 155m - 266m.
Discharge in LPM = 200 LPM to 80 LPM
Now if we consider the minimum discharge of 80 LPM i.e. 4,800 LPH with above mentioned Pump installed in your borewell you need a Water Yield of 2½ inch i.e. 5,919 LPH from the borewell for getting the continuous flow of water.
Suggested Solution -
If the delivery outlet of the Pump is 2 inches, u may install a 1 inch dia ball valve at the discharge nozzle of the suction pipe & return the pipe from the ball valve back into the borewell to control the volume of water discharged from the borewell as per the water yield available from the borewell.
Please Note - We suggest to exercise the Pump Purging solution given in Scenario - I, first, then follow the scenario - II solution for better results.
We wish u all the Best for getting the continuous flow from your borewell.
May u have any further queries, please feel free to contact us at any time.
ALL THE BEST!
YASH D SHAH