Drain Capacity Calculator

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Drain Capacity Calculator

The Drain Capacity Calculator helps you determine the drainage capacity of a pipe based on its diameter, slope, and flow rate. This tool is essential for engineers, contractors, and homeowners who need to ensure proper drainage in plumbing and civil engineering projects.

How to Use the Calculator

  1. Enter the pipe diameter in inches
  2. Enter the pipe slope as a percentage
  3. Enter the flow rate in gallons per minute (GPM)
  4. Click the "Calculate" button to get the drain capacity

Formula

The drain capacity is calculated using the following formula:

Drain Capacity (GPM) = Pipe Area (square inches) × √(Slope (%) / 100) × Flow Rate (GPM)

Where:

  • Pipe Area = π × (Diameter / 2)²

Example Calculation

For a pipe with:

  • Diameter: 4 inches
  • Slope: 2%
  • Flow Rate: 10 GPM

The calculation would be:

  • Area = 3.1416 × (4 / 2)² = 12.5664 square inches
  • Slope Factor = √(2 / 100) = 0.1414
  • Drain Capacity = 12.5664 × 0.1414 × 10 = 17.77 GPM

Importance of Proper Drainage

Proper drainage calculations are crucial for:

  • Preventing water damage to buildings and structures
  • Ensuring efficient wastewater removal
  • Maintaining the longevity of plumbing systems
  • Complying with building codes and regulations
  • Avoiding costly repairs due to inadequate drainage

Applications

This calculator is useful for:

  • Plumbing system design
  • Stormwater management
  • Sewer system planning
  • Agricultural drainage projects
  • Construction site water management

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