Comparison of Cathodic Protection Currents on 70/30 Copper-Nickel and Alloy 625 Piping Systems.
Abstract
The objective of this study was to determine whether the demand on a cathodic protection system changes when the protected pipe material is changed from copper-nickel to alloy 625. Two piping mockups were designed to simulate a probable geometry for a cathodically protected piping system. Each mockup consisted of a 20-ft (610-cm) length of nominal 2-in.- (5-cm-) diameter piping with a zinc anode for cathodic protection inserted in the discharge end of each. One mockup was made with 70/30 copper-nickel pipe and the other with alloy 625 pipe. Protection currents and potential profiles inside the pipes were measured over a 6-month exposure period in natural seawater flowing at 7 ft/s (210 cm/s). The total protection current and sacrificial anode consumption for alloy 625 pipe were half that for copper-nickel pipe. Thus, replacing copper-nickel pipe with alloy 625 pipe in areas close to cathodically protected heat exchangers or hulls will result in less demand on the cathodic protection system, as opposed to the original copper-nickel piping. jg
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1995
- Accession Number
- ADA292953
Entities
People
- HP Hack
- Walter L. Wheatfall
Organizations
- Naval Surface Warfare Center Carderock Division