Calculation of the pump for the well on a country site

The heart of any autonomous water supply from a well or well is a pump. The comfort of using this system, its efficiency of operation, the durability of the well operation and, of course, the quality of drinking water largely depend on its selection. Below are the rules for calculating pumping equipment, which are used in their work by specialists.

Algorithm

1. At the first stage, it is necessary to determine the type of equipment - submersible or self-priming. You should also study the technical characteristics of pumps for wells, to understand what you need. For example, self-priming, due to their principle of operation, can deliver water to the surface from a depth not exceeding 9 m with a built-in ejector and from 7 m without it.

There is also pumping equipment with a remote ejector that can deliver liquid from almost 40 meters.

Tip: you should not use these units because of their low efficiency, as to raise the liquid to the surface, they must pump a part of it into the well, which requires additional energy.

1. Advantages of suction equipment:

• offered in the form of a pumping station. It is sufficiently hydraulically connected to the well with your own hands and you can begin to pump water;
• the pump is located at the top, so it has maximum access for repair and inspection. In addition, it operates in relatively mild conditions than submersible borehole equipment.

Experts recommend the use of such pumps for wells in which the dynamic water level does not fall below 9 m. Otherwise, you need to purchase a submersible borehole pump.

1. Find out the flow rate to understand what kind of pump is needed for the well in your case. Equipment productivity should be 10-30% less. Otherwise, the well will quickly begin to silt.

1. Determine the minimum pump capacity for the well that you need to meet your own needs. For example, for industrial facilities, the calculation depends on the production capacity and the people working for them. Such industrial borehole pumps must be equipped with soft-start automatics or a frequency converter.

Calculation of pumping equipment performance

The overall performance of the equipment should be provided by the project for a specific object. For example, for a private house, the amount of water consumption is often determined from the regulatory data on the points of water intake, which are sink, toilet, bath, etc. It is usually assumed that 200 l of water are needed per person per female. Given that water consumption will occur in the morning and evening.

If we assume that 200 liters will be spent in 2 hours, the average water consumption for a family of 4 people will be about 0.5 m³/ h At the same time, when water is used for other purposes, for example, watering the vegetable garden and garden, this should also be taken into account. On average, 1.5 m is sufficient for these needs.³/ h, therefore, the overall performance of the equipment should be 2 m³/ h

If the addition to a half-cube per hour forces one to acquire a more powerful pump and, consequently, a more expensive one, in order to save, be guided by technological consumption, i.e. in our case 1.5 m³/hour.

Tip: to ensure the remaining half a cube of water, purchase a membrane hydroaccumulator.

Example of calculating pumping equipment for a well

Let's learn how to calculate a pump for a well using an example. Take a family of 4 people who live in a private house on a country plot with a garden and a garden. The calculation will be conducted from the pump with a capacity of 1.7 m³/hour.

It is necessary to find out whether his pressure will be enough to “finish off” to the bath on the second floor.

Tip: do not forget to compare the performance of the pump with the flow rate of the well.

To determine the minimum required head of pumping equipment, there is a formula - H =? H + 10.2xP + ?? P, in which:

• H - min pump head, m;
• P - denotes the pressure in the pipeline system, the standard is 2.5-3 atm;
• ?H - the difference between the highest point of water pumping and dynamic water level in the well, m. If the equipment is suction, then this is the distance between it and the highest point of water pumping;
• ??P - hydraulic losses:
• pipeline - about 10% of its entire length;
• on valves, filters, tees, corners - about 15-20%.

Then we select the brand of pumping equipment and the model for which the technical characteristics are closest to our calculated parameters. After that you need to compare the diameter of the well with the diameter of the selected water pump.

The latter must be less if you use a submersible pump. If the instruction provides for the installation of a downhole adapter, it is necessary to take into account that the pump passes exactly in the place where its static part is fixed.

Recommendations

Often you can meet the requests, type, advise the pump for the well, and then the old pump is very bad.

The answers to many questions will be presented below the recommendations of experts.

1. When choosing a pump for the well, exclude from your priorities the vibration options, the price of which is significantly lower. Such types should be used more in ordinary wells, as due to the work of their communication mechanism, they are gradually filled with sand.
2. Centrifugal submersible pumps are significantly better and more advanced. Well in this case will not zapazkovyvatsya
3. Install pumping equipment not less than 1 m from the filter, this will give an opportunity to get high-quality water.
4. When determining the amount of water flow, also consider peak consumption, and not just average values. Pay attention to the need to obtain water for watering plants, washing a car, etc.

1. The water pump should have 20% of the power reserve of the selected parameter, which will make it possible to create an overpressure in the system, ensuring an acceptable water head. This is due to the use of a filter that can significantly reduce the pressure, moreover, gradual silting of the water pipes results in pressure losses. Such a calculation without special knowledge is very difficult to conduct, so it is better to entrust it to specialists.
2. Lower the pump to a depth that is 1 m below the dynamic level of the well. This will prevent the pump from running dry when its engine is not cooled by water from the outside.

1. Install voltage regulators to protect equipment from power surges. So you can significantly extend the life of the submersible pump, which requires stable parameters of electric current.

1. Keep in mind that the diameter of the pump should be at least 1 cm smaller than the diameter of the well. This will simplify the installation of equipment and its dismantling, as well as significantly extend the life of the pump. For example, a pump for a well 3 inches (3 * 2.54 cm = 76 cm) should be no more than 74 mm in diameter.

Conclusion

When calculating pumping equipment for a well, many factors affecting its operation should be taken into account. If you doubt your abilities, ask for help from specialists. In the presented video in this article you will find additional information on this topic.