Frequently Asked Questions

Questions & Answers

How do I prevent the windmill from over pumping the borehole?

Use a smaller size cylinder or furl the windmill tail.

What is the ideal speed of a windmill or powerhead?

A comfortable speed is between 22 and 25 strokes per minute. For a windmill to maintain this, a wind speed of 24 to 30 kilometers per hour is required.

How to adjust the stroke length to reduce the load?

Lower the pump rods until the plunger lies on the foot valve. Reduce the length of the pump rods under the windmill slightly so that at the end of the stroke, the plunger is about 40mm above the foot valve. The Jooste stroke adjuster facilitates the task to adjust the stroke.

How do I determine what size pipes to use with a borehole cylinder?

A general rule of thumb (without doing all the calculations) is the riser pipes should not be less than half the diameter of the cylinder.

How do I determine the size of the windmill wheel?

The more volume of water required and the higher the total head, the larger the windmill wheel will have to be. One has to determine how much the column of water and the pump rods weigh before you can choose a windmill wheel size.

Size of Wheel Approximate weight it can lift
8 foot wheel 250kg
10 foot wheel 380kg
12 foot wheel 550kg
14 foot wheel 700kg

 

How do I prevent sand from being drawn into the cylinder?

Install the cylinder in a PVC pipe which extends approximately 1.5 meters below the cylinder's inlet.