ABSTRACT

In today’s world, production of various petroleum products, such as petrol, diesel, liquefied petroleum gas (LPG), and several other hydrocarbons, decides the economy of a country. The basic products required to produce these important ingredients are crude oil and natural gas, the main source for which is either offshore or desert. Oil exploration, several miles away from cities and towns and production units such as refineries, poses a big challenge to transport the ingredients to

8.1 Introduction .......................................................................................................................... 185 8.2 Prerequisites to Pipeline Selection ....................................................................................... 186 8.3 Corrosion Problem in Pipeline ............................................................................................. 187

8.3.1 Internal Corrosion ..................................................................................................... 188 8.3.1.1 Formation of Black Powder ....................................................................... 188 8.3.1.2 Moisture Content ....................................................................................... 188 8.3.1.3 Detection of Internal Corrosion ................................................................. 189

8.3.2 External Corrosion on Pipelines ............................................................................... 189 8.3.2.1 Backfill Settlement ..................................................................................... 189 8.3.2.2 Stresses (Residual and Others)................................................................... 189 8.3.2.3 Soil Conditions ........................................................................................... 189 8.3.2.4 Soil Creep................................................................................................... 189 8.3.2.5 Temperature ............................................................................................... 189 8.3.2.6 Microbial Degradation ............................................................................... 190 8.3.2.7 Pipe Pressure .............................................................................................. 190 8.3.2.8 Cyclic Loading Effects .............................................................................. 190

8.4 Selection of Protective Coating for Underground Pipelines ................................................. 190 8.4.1 Pipeline Coatings ...................................................................................................... 190

8.4.1.1 Coal Tar Coatings ...................................................................................... 190 8.4.1.2 FBE Coatings ............................................................................................. 191 8.4.1.3 Multilayer Coatings .................................................................................... 191

8.4.2 Protection of Pipeline by Cathodic Protection ......................................................... 192 8.4.3 Field Joint Coatings .................................................................................................. 192 8.4.4 Rehabilitation Coatings ............................................................................................ 192

8.5 Coatings with Integrity ......................................................................................................... 193 8.6 Conclusion ............................................................................................................................ 194 References ...................................................................................................................................... 195

these sites, the main reason being that both are inflammable, and thus, any leakage can cause severe accident, leading to explosion. Therefore, transporting the same through railcar, truck, or ship over long distances may be economical but may not be safe. Hence, the alternative method of transporting them through underground pipelines is not only quick but is very safe, though with higher initial investment. A pipeline carrying products such as crude oil, refined oil, and chemicals like naphtha, ethylene, propylene, and so forth over long distances ranging from 10 to even 1000 km, passing through land, rivers, sea, mountains, marshy areas, and private and public land and crossing other services like roads, railways, transmission lines, underground pipes/cables, and so forth, is called a “cross-country pipeline” (CCP). CCP has been in use for transportation of water, petroleum liquids, and gases for the last 70-80 years in the developed countries. In India, there is approximately 25,000 km of pipelines, transporting crude and gas, and some of the pipelines have been installed and operated for the past 40-50 years [1,2].