Corrosion is a naturally occurring phenomenon commonly defined as the deterioration of a substance (usually a metal) or its properties because of a reaction with its environment. Like other natural hazards, corrosion can cause dangerous and expensive damage to everything from offshore structures and pipelines to ship hulls and superstructures, inner-hull tanks in fuel tankers, underwater pipes, etc.
Coatings are defined as a thin layer of solid material on a surface that provides improved protective, decorative, or functional properties.
They are a liquid, liquefiable, or mastic composition that, after application to a surface, is converted into a solid protective, decorative, or functional adherent film.
Protective coatings are applied to a surface to protect the substrate from corrosion.
An effective way in which to protect metal from corrosion is by physical isolating a substrate from its environment by applying protective coatings.
Coatings protect against corrosion through one of the following ways: they block necessary elements from coming to together to start the corrosion process, actively
prevent the electrochemical reaction from occurring, or steer the corrosion process in a direction that is will not harm the asset.
Types of Protective Coating:
Barrier -- Protect by preventing water, oxygen, and electrolytes from contact with an underlying metal
Inhibitive -- Coatings that contain chemicals that work to hinder corrosion
Sacrificial -- Thin metal layers that have lower electrode potential values or those having higher levels in the electrochemical series are applied
OCS has received Notification of Award (NOA) from ONGC confirming contract award for Protective Coating of Process Platforms (PCPP). For the first time, ONGC is performing vessel-based fabric maintenance activities of process platforms in the offshore. This is massive and complex work involving marine spreads OCS has secured it in a very competitive environment. The power of collaboration, clarity, and coordination between OCS and PSSI led to this result.
Offshore site survey will begin within a month and vessel-based execution will begin in Oct 21 and will continue till May 2023 (excluding monsoon seasons). There are 32 offshore structures to be painted under this campaign involving 5 to 6 vessels including accommodation barges, anchor handling tugs and crew boats. While OCS will manage entire project, PSSI will support to manage marine interfaces. This portfolio demonstration will allow OCS to expand its reach into EPC projects involving marine spreads.
The project is divided between four parts: 1. Marine Spreads, 2. Surveying, 3. Fabrication, 4. Painting (Protective Coating)
Marine spread means the marine part of the Survey Equipment, with all appurtenances thereof, together with captain, full crew and technical team to be mobilised and used on site.
It includes two functions: Barge Inspection and Deck Space Estimation.
Surveying function includes 1. Anchor Pattern Survey, 2. DGPS (Differential GPS) and 3. Pre Engineering Survey
Fabrication function includes 1. Jumping Ropes, 2. Checkered Plates and 3. Helideck Net
Materials typically used in protective coatings are: Polymers, epoxies, and polyurethanes for non-metallic coatings, Zinc, aluminum, and chromium for metallic coatings.
Application - coatings, which includes paints, can be: sprayed, welded, plated, or applied with hand tools (specific to the surface, environment, and application goals). The process for applying protective coatings involves: Surface preparation, application of a primer, a full coating, use of a sealant.