A cathodic protection system is to be designed for a 600 m long and 110 mm diameter buried pipeline coated with fusion bonded epoxy (FBE). The current density required for FBE coated structures is 0.18 mA/m^2. It is required to use horizontal anodes 8 ft. below the ground with 15 ft. spacing. The anode material available is high silicon-cast iron with a consumption rate of 0.5 kg/A-yr. The diameter and length of anodes are 30 cm and 300 cm respeqtively. The weight of each anode is 50 kg. Anode to soil resistance is measured to be 0.24 ohm. The soil resistivity is 2,500 ohm-cm. It is aimed to protect the structure for a period of 22 years. In order to design this CP system, determine, (a) Current required (A) (b) Total number of anodes (c) Total resistance

A cathodic protection system is to be designed for a 600 m long and 110 mm diameter buried pipeline coated with fusion bonded epoxy (FBE). The current density required for FBE coated structures is 0.18 mA/m^2. It is required to use horizontal anodes 8 ft. below the ground with 15 ft. spacing. The anode material available is high silicon-cast iron with a consumption rate of 0.5 kg/A-yr. The diameter and length of anodes are 30 cm and 300 cm respeqtively. The weight of each anode is 50 kg. Anode to soil resistance is measured to be 0.24 ohm. The soil resistivity is 2,500 ohm-cm. It is aimed to protect the structure for a period of 22 years. In order to design this CP system, determine, (a) Current required (A) (b) Total number of anodes (c) Total resistance

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter1: Atomic Structure

Section: Chapter Questions

Problem 6RQ: How many valence electrons are generally contained in materials used for insulators?

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