Offshore well casing cathodic protection

Conference · Thu Jan 01 04:00:00 EST 1987

OSTI ID:7244337

Hamberg, A; Orton, M D; Smith, S N

Many papers have been published on cathodic protection of offshore platforms, but few references are made on the extent of protection of the well casings attached to the structures. Others reported tests in the Arabian Gulf which showed the galvanic anodes protected the wells to a depth of approximately 3200 ft (976 m) and that 300 A were required to completely protect bare well casings attached to a six-well platform in 40 ft (12 m) of water. Recent tests in deeper water (170 ft (52 m() showed the structure galvanic anodes deliver approximately 8 A per well and protect the bare casing to approximately 3000 ft (915 m). An impressed current cathodic protection system with 600 A applied to anodes placed 400 ft (122 m) from the structure protected the structure and six bare well casings to 8000 ft (2440 m). A protection criterion of 0.1 mA/ft/sup 2/ (1.1 mA/m/sup 2/) in the lower cemented zone was proposed. Impressed current anodes placed closer than 400 ft (122 m) from the structure did not protect the wells to the required depth.

• OSTI ID: 7244337
• Report Number(s): CONF-870314-
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
36 MATERIALS SCIENCE
360105 -- Metals & Alloys-- Corrosion & Erosion
42 ENGINEERING
420206 -- Engineering-- Mining & Drilling Equipment & Facilities-- (1980-1989)
ALLOYS
ANODES
ARABIAN SEA
CATHODIC PROTECTION
CORROSION PROTECTION
CORROSION RESISTANCE
ELECTRODES
INDIAN OCEAN
NATURAL GAS WELLS
OFFSHORE PLATFORMS
OIL WELLS
PERFORMANCE
SEAS
SURFACE WATERS
TESTING
WELL CASINGS
WELLS