Design Calculations
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Design Calculations Length of line: - 2 Km Diameter: - 2 Inch Total Surface Area: D x π x L = 0.0512 x 3.14 x 2000 = 318.78 M² Say Total surface area to be protected 320 M² Current Density Chosen= 0.25mA/m² at 30º C OR 0.41mA/ m² at 55º C Total Current Required For 320m² x 0.41mA = 0.131A Considering Coating Deficiency as 5% Final Current Requirement: = 16mA OR 0.016A Ground Bed Resistance using Dwight's Formula for a single vertical anode = 5.1128Ω Based on Soli Resistivity = 1000Ω-cm and choosing 15lbs Zinc anode, size 1.4"x1.4"x30" package size 5"x38", 50lbs weight. Driving Potential of the anode = 1.1-0.95 = 0.15 volts (assuming SRBs presence) Design Life = 25 Years (15lbs Zinc anode consumption rate 0.27kg/Year)
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CALCULATIONS
Transcript of Design Calculations
Design Calculations
Length of line:- 2 Km
Diameter: - 2 Inch
Total Surface Area: D x π x L = 0.0512 x 3.14 x 2000 = 318.78 M²
Say Total surface area to be protected 320 M²
Current Density Chosen= 0.25mA/m² at 30º C OR 0.41mA/ m² at 55º C
Total Current Required For 320m² x 0.41mA = 0.131A
Considering Coating Deficiency as 5%
Final Current Requirement: = 16mA OR 0.016A
Ground Bed Resistance using Dwight's Formula for a single vertical anode = 5.1128Ω
Based on Soli Resistivity = 1000Ω-cm and choosing 15lbs Zinc anode, size 1.4"x1.4"x30" package size 5"x38", 50lbs weight.
Driving Potential of the anode = 1.1-0.95 = 0.15 volts (assuming SRBs presence)
Design Life = 25 Years (15lbs Zinc anode consumption rate 0.27kg/Year)
