India's Deepwater Oil & Gas Exploration is Accelerating:
 Why Corrosion & Metallurgical Testing Matter More Than Ever

As India expands exploration into deepwater and ultra-deepwater environments, material reliability becomes a critical part of offshore engineering

India's offshore oil and gas sector is entering an important phase of development.

A recent development reported on 10 August 2026 highlighted a non-binding agreement between ONGC and Shell Energy India to explore opportunities in deepwater and ultra-deepwater oil and gas exploration, along with opportunities related to LNG sourcing. The collaboration reflects the increasing focus on India's offshore hydrocarbon resources and the need to bring together exploration expertise and advanced technology. (The Economic Times)

This development comes at a time when India is actively expanding its offshore exploration programme. The Directorate General of Hydrocarbons (DGH) currently lists OALP Bid Round X with 25 blocks and OALP Bid Round XI with 21 blocks, including significant deepwater and ultra-deepwater acreage. (Directorate General of Hydrocarbons)

But exploring deeper waters brings another important engineering question:

Can the materials, welds, coatings and components used in these environments reliably withstand the demanding conditions throughout their service life?

This is where corrosion testing and metallurgical testing become critical.


Why Deepwater Environments Are Technically Challenging

Offshore equipment operates in environments that can be significantly more demanding than conventional onshore facilities.

Depending on the location and application, materials may be exposed to:

The combination of pressure, temperature, corrosive media and mechanical stresses can create complex degradation mechanisms.

A material that performs satisfactorily in a conventional laboratory environment may behave very differently when exposed to a combination of these conditions.

Therefore, material selection cannot be based solely on nominal chemical composition or mechanical strength.

The material must be demonstrated to be suitable for its intended service environment.


Corrosion: One of the Major Risks in Offshore Equipment

Corrosion can affect almost every stage of an offshore asset.

From subsea equipment and pipelines to valves, pressure-containing components, structural members and process equipment, corrosion can lead to:

Offshore assets are particularly sensitive because inspection and maintenance can be significantly more difficult and expensive than onshore.

This makes corrosion prevention and material qualification at the design stage particularly important.


Where Metallurgical Testing Becomes Critical

Corrosion resistance is only one part of material performance.

For critical offshore components, engineers also need to understand:

Chemical Composition

Verification of alloy chemistry helps ensure that the material supplied corresponds to the specified grade.

Advanced chemical analysis can be used for major and trace elements required for material verification.

Microstructure

Metallographic examination can reveal:

Microstructure can have a significant influence on corrosion resistance, toughness and cracking susceptibility.

Mechanical Properties

Tensile strength, yield strength, elongation and hardness provide essential information about the mechanical condition of the material.

For critical applications, additional testing such as impact, fracture and fatigue testing may also be required.


Sour Service: When H₂S Changes the Material Selection Challenge

One of the most important considerations in oil and gas materials is exposure to hydrogen sulphide (H₂S).

H₂S-containing environments can cause serious forms of environmentally assisted cracking.

Two important mechanisms are:

Hydrogen Induced Cracking – HIC

Hydrogen generated during corrosion can enter susceptible steels and contribute to internal cracking.

HIC testing helps evaluate the susceptibility of materials to hydrogen-related cracking under controlled sour-service conditions.

Sulphide Stress Cracking – SSC

SSC is a form of environmentally assisted cracking that can occur when susceptible materials are exposed to H₂S-containing environments while subjected to tensile stress.

Material qualification through appropriate SSC testing is therefore important for components intended for sour service.


Stress Corrosion Cracking and Environmental Cracking

Offshore materials may also be exposed to combinations of:

Material + Environment + Stress

This combination can result in Stress Corrosion Cracking (SCC).

Unlike general corrosion, SCC can produce cracking and loss of structural integrity even when the overall amount of metal loss appears relatively small.

This is why corrosion testing must go beyond simply asking:

"Does the material corrode?"

The more important engineering question is:

"How will the material behave under the actual combination of environmental and mechanical conditions experienced during service?"


Electrochemical Corrosion Testing: Understanding Corrosion Behaviour Faster

Modern corrosion engineering increasingly uses electrochemical techniques to obtain detailed information about corrosion behaviour.

At Subodh Material Technologists, electrochemical corrosion testing forms an important part of our advanced corrosion testing capabilities.

Electrochemical Impedance Spectroscopy – EIS

EIS can be used to investigate electrochemical behaviour at the material/environment interface and is particularly valuable for studying:

Potentiodynamic Polarization

Potentiodynamic polarization can provide information about:

These techniques can complement conventional exposure testing and provide engineers with deeper insight into corrosion mechanisms.


High Pressure and High Temperature Corrosion Testing

Deepwater and oil & gas applications may require materials to operate under combinations of pressure, temperature and corrosive environments.

Laboratory autoclave testing can be used to reproduce controlled high-pressure/high-temperature environments for evaluating material behaviour.

At Subodh Material Technologists, our corrosion testing capabilities include HPHT autoclave-based testing, supporting evaluation of materials under demanding environments involving corrosive gases such as CO₂ and H₂S.

This type of testing can be particularly valuable when conventional atmospheric corrosion tests cannot adequately represent the intended service environment.


Corrosion Testing Beyond HIC, SSC and SCC

A comprehensive offshore material qualification programme may require several complementary tests.

At Subodh Material Technologists, our corrosion testing capabilities include:

Sour Service Testing

Accelerated Corrosion Testing

Advanced Electrochemical Testing

Hydrogen-Related Testing


Metallurgy and Corrosion: Why Both Matter

One of the most important advantages of an integrated testing laboratory is the ability to look at corrosion behaviour and material structure together.

For example, when a component shows cracking after corrosion exposure, simply reporting the presence of cracks may not answer the engineering question.

A complete investigation may require:

Chemical Analysis

↓

Mechanical Testing

↓

Metallography

↓

Corrosion Testing

↓

Fractography / Failure Analysis

↓

Root Cause Evaluation

This integrated approach can help determine whether a failure is associated with:


How Subodh Material Technologists Can Support India's Growing Offshore Sector

As India's exploration moves into increasingly challenging offshore environments, testing laboratories have an important role to play in the material qualification and reliability chain.

Subodh Material Technologists Pvt. Ltd. provides an integrated range of corrosion, metallurgical, chemical and mechanical testing services for critical engineering materials and components.

Our capabilities enable customers to evaluate materials from multiple perspectives rather than relying on a single test.

Our capabilities include:

Corrosion Testing

HIC • SSC • SCC • Autoclave • Salt Spray • Modified Salt Spray • Moist SO₂

Electrochemical Corrosion Testing

EIS • Potentiodynamic Polarization • Corrosion Behaviour Evaluation

Metallurgical Testing

Metallography • Microstructure Evaluation • Failure Analysis • Fractography

Chemical Analysis

ICP-OES • Carbon/Sulphur • Oxygen/Nitrogen/Hydrogen • Material Chemistry

Mechanical Testing

Tensile • Hardness • Impact • Fatigue • Fracture Toughness • Elevated Temperature Testing

Weld Testing

Mechanical and metallurgical evaluation of welded components and joints.


Supporting Material Reliability from Laboratory to Field

The expansion of India's deepwater and ultra-deepwater exploration programme represents a significant engineering opportunity.

However, successful offshore development depends not only on discovering hydrocarbons but also on ensuring that the materials, components and systems used to explore, produce and transport them remain reliable in demanding environments.

The recent ONGC–Shell collaboration is one example of the increasing focus on India's offshore potential. (The Economic Times)

As offshore exploration expands, material qualification, corrosion assessment and metallurgical evaluation will become increasingly important parts of the engineering lifecycle.

At Subodh Material Technologists, our objective is to provide technically reliable testing that helps engineers make informed decisions about material selection, qualification, corrosion resistance and service suitability.


Engineering the Future of India's Energy Infrastructure

India's move toward deeper offshore exploration will require advanced technology, robust materials and rigorous engineering controls.

Corrosion testing and metallurgical testing are not simply laboratory requirements—they are tools for managing risk, improving reliability and extending the service life of critical assets.

With comprehensive capabilities spanning corrosion, electrochemical testing, metallurgy, chemical analysis and mechanical testing, Subodh Material Technologists is positioned to support the evolving requirements of India's oil & gas, offshore and heavy engineering sectors.

Need Material or Corrosion Testing for an Offshore or Oil & Gas Application?

Talk to the technical team at Subodh Material Technologists.

Corrosion Testing | Metallurgical Testing | Electrochemical Testing | Chemical Analysis | Mechanical Testing

Email: info@subodhlabs.net
Website: subodhlabs.net