Posted in Cathodic Protection / Design on May 8th, 2024
Cathodic Protection Of Offshpre Structures
Offshore structures comprise fixed platforms, mobile rigs, sub-sea pipelines, mooring buoys, harbours, and jetties. These are made of steel, but sometimes of concrete. All categories need cathodic protection to prevent the steel corroding in sea water. Full cathodic protection requires that all points of the steelwork have steel/sea-water potentials more negative than -0.8 V wrt Ag/AgC1.
The protective current...
Hazardous Area Classification Impact on Earthing Systems in Oil & Gas Installations
Hazardous Area Classification
Oil & gas installation has areas which are classified as being Zone 1 or Zone 2 according to IEC 60079. With regards to explosion ignition of flammable gases and vapours, it is necessary to take special precautions during installations. Whever possible, live conductor installation is avoided as the possiblity intentional or accidental contact with...Earthing System in Oil & Gas Installations
In oil and gas installations, earthing systems play a crucial role in ensuring safety and mitigating risks associated with electrical faults and preventing hazardous incidents such as fires, explosions, and equipment damage due to static electricity buildup or lightning strikes.
Some functional earthing installations commonly used in Oil & Gas industry are:- Equipotential Bonding
- This involves connecting all metallic structures...
Posted in Design on April 30th, 2024
Selection of Electric Motor Rating to Match Driven Equipment
Factors in Electrical Motor Selection
The rating of an electric motor should be higher than that of its driven equipment by a suitable margin. The selection of this margin is often made by the manufacturer of the driven equipment, unless advised otherwise. The actual choice depends on various factors such as- Function of the driven equipment - pump, compressor,...
Posted in Design on April 29th, 2024
Electric Motors Derating factors
Like any other power system equipment, motors need to be derated to suit a high ambient temperature. Equipment that are usually manufactured in America, UK and Europe are based on a maximum design temperature of 40◦C. For higher ambient temperatures, e.g. 50◦C as found in the Middle East, Asia and Australia, the continuous duty output power and supply...