Solar Water Pump Pipes: Pipe Sizing Chart

Pipe Sizing Chart for solar water pumps

Solar water pumps require a pipe sizing chart to determine the required output pressure and the pipe size. It is essential to do correct pipe sizing math to figure out pressure losses. A pipe sizing chart helps to get the required figures concerning flow in US GPM, velocity, and the required pipe size in plastic, steel or copper pipe material. Due to these many calculations that are required, charts have been noted to be a quicker and suitable way of determining pressure losses in a solar water pump system.

Pipe sizing, pressure and flow rate

A solar water pump generally requires a larger pipe. This is because it is hard to force the water through a small pipe. Pressure loss is evident as water flows through due to the resistance of the walls. This is known as friction loss. The pipe size and the flow rate determine the friction losses. Greater friction loss results when smaller pipes are provided with higher flows. The size of the pipe that will provide the optimal flow from the pump is always bigger than the pipe size of the pump outlet, which is a general rule. In short: a 11/2″ pipe is likely to be attached to an outlet pipe that is 1″. In order to save money, solar water pump manufacturers tend to use smaller size outlets and inlets. To make this work simpler, a pipe sizing chart is suitable for deriving these measurements.

Chart calculation essentials - sample

The Williams and Hazen Formula of analyzing a friction chart is used in majority of the cases. A Head Loss of 100’ of pipe is discussed while a 10 year old pipe is assumed. In the chart, the US GPM, velocity, and the required pipe size in a plastic, steel or copper pipe material are filled using the above estimations. When selecting the required pipe sizing it is necessary to get the size from the chart, depending on the pipe material. In order to get the effective length of the solar water pump pipe from the fittings, the actual and equivalent length of the pipe should be added. Pipe sizing charts help to identify the size of the pipe, the flow rate, velocity, and the type of pipe. Always bear in mind that 1 PSI=2.31 Feet of Head. This is the basis of pipe sizing since every pipe curve is written in PSI (pound/square inch) or FoH (Feet of Head). This means that at one point, it will be required to change everything into feet of head in order to proceed with the curve and pick a pump. It is difficult to troubleshoot or choose a pump without knowledge of PSI and FoH. Always ensure that the size of the pipe in the solar water pumping application is not very small as this could decrease the flow rate. The height in which water is being lifted also has a significant effect on the flow rate and friction loss. The length and diameter of the pipe can help to solve the differences. Therefore, an optimum pipe sizing can help to reduce the power requirements.