Bore Pump Installation


Installing a Submersible Bore / Well Pump

 

Please feel free to use the info on this website as a guide only. There are different methods of installing a bore pump.

Please check the following points to ensure correct pump operation.

  • Pump should not be installed in water over 40 degrees centigrade.
  • Direction of rotation of pump must be checked prior to installing in the bore. On three phase pumps, check for direction of rotation before installing pump in the bore. Pump should run anti-clockwise when looking down on pump. Should direction be wrong change any 2 leads at termination box. Motor should be protected with the recommended thermal overloads.
  • Correct cable size must be used. (check with electrician).
  • Do not use pump to pump sand or gravel. The bore must be developed or rehabilitated and be producing clean water prior to installation.
  • If the pump is being used as a pressure system, use the recommended pressure tanks or pressure switch and do not allow pump to short cycle.
  • Do not run pump dry.
  • Pump is not suitable for use in some types of corrosive water. (If unsure have water tested and seek advice).
  • If the pump is throttled back Fig 8. to less than 0.5lps, then an Auto Control Box with water level monitoring probes must be used instead of the standard switch.
  • Pump should be installed using suitable support cable.
  • Starting voltage at the pump and frequency must be correct.
  • Bore suitability check the following.
    • Water quality.
    • Is the bore straight.
    • Is the bore correctly cased.
    • Has the bore got a sand screen.
    • Does the bore have sufficient capacity to suit the pump.
  • Check the burst pressure of the pipe to make sure that it is compatible with the pump pressure.  Refer to section below on Polythylene Pipe Class

  

INSTALLING PUMP IN BORE

There are many different ways to install a Submersible Bore / Well Pump. Here is one method of Pump Installation:

  • Splice the cable from the bore pump to the submersible cable refer to section below on Cable Splice
  • Feed the other end of the submersible cable through the hole in the bore cap and fix. Fig 1. Appropriate electrical fitting may need to be purchased if it is not part of the bore cap. Fig 2.
  • Wire the submersible cable to the appropriate Control Device as seen in Fig 1.
  • Lay the pump with cable along the ground from the top of the bore, so that the pump is at the bore end.
  • Lay the pipe and block the ends of the pipe so that no stones, dirt or gravel can enter the ends of the pipe and lay the pipe along the ground along-side the submersible electrical cable and pump. It is very important that you don’t kink or bend the poly (if using poly pipe) as this can result in the poly splitting later.
  • Install the shroud Fig 3. (if needed) refer to section below on Bore Pump Shroud.
  • Connect the bore pump to the pipe and bore cap using appropriately rated pipe fittings.
  • Make sure there is a non-return valve included on the line.

bore pump fittings

  • Lay the water level monitoring probes (if needed) next to the pipe.
  • Tape the probes to the pipe every 3 meters to prevent snarling of cable. Use a strong tape such as duct tape.
  • Attach the stainless steel support cable Fig 5. refer to section below on Stainless Steel Support Cable
  • You should now see bundled together and laid out on the ground, the pipe and probes taped together. Not taped, but laying along side them is the electrical cable and the safety cable.
  • MAKE SURE THE SAFETY SUPPORT CABLE IS CONNECTED TO THE BORE CAP AND SECURED.
  • The bundle of pump, pipe, cable, probes and safely cable can now be carefully lowered into the bore taking care not to cut or chafe the cable insulation on the bore casing.
  • Lower the pump into the bore slowly without force to the required depth. Your bore report will usually have a recommended ‘pump set depth’.  Make sure the poly doesn’t kink at all when lowering it into the bore as it may possibly cause the poly to split later when under pressure.
  • DO NOT SET THE PUMP AT THE BOTTOM OF THE BORE.
  • MAKE SURE THE PUMP IS POSITIONED ABOVE THE CASING SLOTS or at the recommended pump set depth on the bore report.
  • Pull on the bore pump support cable so the weight of the pump is on the cable and then fix it.

I will supply more images of a pump being installed down a bore / well soon

 

PUMP START UP
Partially throttle pump Fig 8. and run until the water is clear of sand or any impurities. Gradually open the throttle valve until the pressure gauge Fig 9. is at the required operating pressure. If the pressure gauge continues to drop once valve is set the water level is dropping in the bore. Close the valve further until a steady operating pressure is shown on the gauge.
If the capacity of the bore is unreliable a flow switch with timer or bore probes should be used to protect the pump from running dry.

BORE PUMP SHROUD
If the pump is being installed below the water inlet level, then a pump shroud should be used.  A shroud should also be used in:

  • Cascading bores
  • Low yielding bores
  • Top feeding bores
  • If the bore casing is greater than 5”diameter
  • If the pump is throttled back more than 25% of it’s rated flow
  • If the position of the slots in the casing is unknown
  • If the pump is being installed in a dam or river
  • If the pump is to be set below the production level of the bore

Pump shrouds are installed over the body of the pump and motor. The shroud  protects the pump from damage from falling sand and ensures that the water flow past the motor is sufficient to achieve adequate cooling of the motor.  Failure to install a shroud can result in motor shutdown and failure.
A pump shroud can easily be made from PVC pipe.
Buy a PVC Shroud Adapter

CABLE SPLICE
After first checking cable size for suitability, proceed with the cable splice. This is a very important step and extreme care should be taken. On three phase pumps, check for direction of rotation before installing pump in the bore. Pump should run anti-clockwise when looking down on pump. Should direction be wrong change any 2 leads at termination box. Proper submersible heat shrinks need to be used to seal underwater joins and all systems need to be properly earthed.
All wiring should conform to national and local codes and be done by a competent electrician.

STAINLESS STEEL SUPPORT CABLE
Never allow the pump weight to be supported by the electric cable alone. Stainless steel safety cable must always be installed to support the pump.  A strong saddle is often used to connect the safely cable to the hole in the top of the bore pump.
The support cable should be secured to the well / bore head fitting which in turn should be able to transfer the weight to the concrete surface pad around the top of the bore casing.
Stainless steel support cable is required to provide insurance for those unfortunate times when the metric poly pipe breaks or loosens in the fittings. It is used for lifting the pump in and out of the bore and to support the pump in the bore so there is no pump weight on the electrical cable or the rising main.

POLYTHYLENE PIPE CLASS
Water delivery pipe, needs to be of sufficient pressure rating and diameter to sustain pressure loads and still deliver adequate flow rates without being restricted by friction loss. All pipe fittings need to be of the same or better pressure rating as the rising main.
Pumps installed down to 120 metres are commonly done so on 40 or 50 mm. Class 12 polythene pipe. Installations to 150 metres should use class 15 polythene up to 2.2 Kw motor size. For depths greater than 150 metres or motor sizes larger than 2.2 Kw use steel or galvanised pipe to install the pump. It is very important to check the pressure rating of the pipe and make sure it is compatible with the
pump pressure.
If you take the pump details along with the depth that you are installing the pump at, to your irrigation store, they will let you know exactly what size pipe to get.

There are many variations to the following method of bore pump installation. I have included these instructions as a general guideline. If you have your own method and have photos which you would like me to include on this site, please contact me

All the accessories needed to install a bore pump are listed on my BORE PUMP ACCESSORIES page

 

The are many different ways of installing a submersible bore pump. Here is an example only of a submersible pump installation.
CLICK HERE to view a video on installing a submersible bore pump:

Fig 1

Bore pump is spliced to submersible cable. Submersible cable is fed through the bore cap and wired to the Control Device

Bore pump is spliced to submersible electrical cable which is threaded through the appropriate hole in the bore cap and wired to the Starter Box (or control box).

 

Fig 2

Bore Cap Well cap

There are many different types of bore caps available. Each one should have a slot for the submersible cable to be threaded through making sure it is secure.

Fig 3

PVC Shroud Adaptor

PVC Shroud Adaptor

 

Fig 4

Submersible Electric Cable / Electric Drop Cable

Submersible Electrical Cable or Electric Drop Cable. There is different ratings for insulated submersible cable so it is very important that you select the correct cable for your situation.

Fig 5

Safety Wire / Support cable

Stainless Steel safely wire or support cable is vital to support the bore pump in the well so that the weight is on the cable and not the pump.

 

Fig 6

Shackle or saddle used to secure safety cable to pumpHole in bore pump for safety wire

A saddle or shackle can be used to secure the support cable to the Pump. Every bore pump should have a hole at the top of the pump for positioning of the support cable.

 

Fig 7

Irrigation fittings will need to be fitted to the bore cap to secure the pipe to the bore cap

Special irrigation fittings need to be purchased to secure the mains pipe to the bore cap.

 

Fig 8

Tap used to throttle back the flow of water from the bore

A tap installed at the top of the bore can be used to throttle back or adjust the flow of water from the bore.

manifold kit for bore pump installation using a pressure tank

When including a pressure tank on the line, use a manifold kit which ensures that all the items are correctly spaced

If using a larger stand alone tank, then the braided connection will connect to the socket where the tank is and this is then connected to the tank

 

Fig 9

Pressure Gauge used to monitor pump system discharge pressure

Gauge used for monitoring the water pressure from the bore.

 

Fig 10

Heat Shrink Splice Kit waterproof tape

There are many different ways to splice submersible cables.  Heatshrink, Shrinkwrap or Waterproof tape along with connectors create a watertight splice