Choosing the Perfect Submersible Pump for a 1200 Feet Deep Bore Well

When selecting the right submersible pump for a 1200 feet deep bore well with a 6-inch diameter, several critical factors must be considered, including the required flow rate, total dynamic head (TDH), friction loss, and the specific characteristics of the pump. This article will guide you through the process of determining the ideal pump for your deep well application.

Key Considerations

Total Dynamic Head (TDH)

The Total Dynamic Head (TDH) is a crucial factor that determines the pressure required to lift water to the desired height and account for any pressure losses within the system. For a 1200 feet deep well, the vertical lift is the primary component of the TDH. Additional pressure requirements, such as friction loss in the piping and elevation changes, must also be considered for an accurate calculation.

A rough estimate of friction loss can be calculated using the Hazen-Williams equation. However, a general rule is that for every 1000 feet of lift, you can expect a friction loss of around 100 feet. Therefore, for a 1200 feet lift, the friction loss would be approximately 120 feet, leading to a total TDH of around 1320 feet.

Flow Rate

Determining the required flow rate in gallons per minute (GPM) is essential for your specific application. The flow rate will significantly influence the horsepower and number of stages needed for the pump. Accurate flow rate information can be obtained from the local irrigation department or by estimating based on your project needs.

Pump Stages

Submersible pumps typically have multiple stages to increase pressure. For a depth of 1200 feet, you will likely need a pump with between 5 to 10 stages, depending on the flow rate and efficiency of the pump.

Each stage can typically lift water around 20-40 feet. Therefore, to meet the 1200 feet lift, you will need to add 6 to 10 stages to the pump. This will ensure that the pump can efficiently lift the water to the surface and maintain the necessary pressure within the system.

Horsepower

The horsepower (HP) required can be estimated using the formula:

HP (GPM × TDH × 0.00833) / Pump Efficiency

For a typical submersible pump, you can expect efficiencies around 60-80%. Using this formula, we can calculate the necessary horsepower for a given flow rate and total dynamic head.

Example Calculation

Assuming a flow rate of 10 GPM and a total dynamic head of about 1300 feet (1200 feet lift 100 feet friction loss), the calculation would be as follows:

Total Dynamic Head (TDH): 1300 feet Flow Rate: 10 GPM Pump Efficiency: 70% (0.7)

Plugging these values into the formula:

HP (10 × 1300 × 0.00833) / 0.7 ≈ 18.9 HP

This suggests a pump in the range of 20 HP would be suitable.

Recommendations

The recommended pump type for a 1200 feet deep bore well with a 6-inch diameter would be a multi-stage submersible pump that is specifically designed for deep well applications. The horsepower would be approximately 20 HP, with the actual value varying based on specific flow requirements and pump efficiency.

The number of stages would range from 6 to 10, depending on the exact flow rate and efficiency of the pump. This will ensure that the pump can efficiently lift the water to the surface and maintain the necessary pressure within the system.

Conclusion

Selecting the right submersible pump for a 1200 feet deep bore well is a critical task that requires careful consideration of several factors. By understanding the total dynamic head, flow rate, pump stages, and horsepower, you can choose the perfect pump to ensure the efficiency and reliability of your water extraction project.