Dr GH Thanki, Director and Principal Consultant Corrosion Control and Monitoring Consultancy, discusses the nuances of maintaining stainless steel.
That’s a clever analogy! Stainless steel is indeed a workhorse in many industries, known for its durability, corrosion resistance and versatility. However, just like a workhorse needs regular care and maintenance to perform at its best, stainless steel also requires proper care to maintain its ‘horsepower’ (or in this case, its corrosion resistance and overall performance).
Here are some tips to help keep stainless steel in top condition:
1. Regular cleaning: Wash stainless steel surfaces with mild soap and water to remove dirt and grime.
2. Avoid harsh chemicals: Never use bleach, acid or abrasive cleaners, as they can damage the surface.
3. Dry thoroughly: Dry stainless steel surfaces to prevent water spots after cleaning
4. Avoid scratching: Use soft cloths and avoid scratching the surface with sharp objects.
5. Passivation: For heavily used or exposed stainless steel, consider passivation to restore its corrosion- resistant properties.
Following these tips, you can keep your stainless steel ‘workhorse’ running strong and performing at its best. but before it is used in a horse format, certain precautions are mandatory to get maximum horsepower. To get the maximum ‘horsepower’ out of stainless steel, certain precautions and processes are essential:
1. Selection of grade: Choosing the right stainless steel grade for the specific application is crucial.
2. Surface finish: The surface finish can affect corrosion resistance and performance. A smooth finish can help prevent corrosion.
3. Heat treatment: Proper heat treatment can enhance stainless steel’s mechanical properties and corrosion resistance.
4. Passivation: Passivation removes impurities and enhances corrosion resistance.
5. Testing and inspection: Regular testing and inspection ensure the material meets specifications and standards.
6. Storage and handling: Proper storage and handling prevent damage and contamination.
7. Fabrication techniques: Using appropriate fabrication techniques, such as welding, cutting, and forming, helps maintain the material’s integrity.
8. Quality control: Implementing quality control measures throughout the production process ensures consistency and reliability.
By following these precautions and processes, you can unlock the full potential of stainless steel and get the maximum ‘horsepower’ for your application!
Weather resistant and environment-friendly
Stainless steel is generally considered a weather- and environment-friendly material due to its corrosion-resistant properties, durability and recyclability. However, its performance can vary depending on the specific environment and conditions. Here’s a detailed explanation:
Advantages
1. Corrosion resistance: Stainless steel contains chromium, which forms a protective oxide layer, making it resistant to corrosion in many environments.
2. Durability: Stainless steel can withstand harsh weather conditions, such as rain, snow and extreme temperatures.
3. Low maintenance: Stainless steel requires less maintenance compared to other materials, as it doesn’t need painting or coating.
4. Recyclability: Stainless steel is 100 per cent recyclable, reducing waste and conserving natural resources.
Precautions in corrosive environments
1. Marine environments: In coastal areas, stainless steel can corrode due to high salt concentrations. Use marine-grade stainless steel (e.g., 316L) and consider additional coatings or cathodic protection.
2. High-temperature environments: Above 500°C, stainless steel can lose its corrosion resistance. Use heat-resistant grades (e.g., 310S) and ensure proper cooling systems.
3. Acidic environments: In environments with high acidity (e.g., chemical plants), use acid-resistant grades (e.g., 904L) and consider additional coatings or linings.
4. Chloride-rich environments: Chlorides can cause pitting corrosion. Use chloride-resistant grades (e.g., 316L) and ensure proper cleaning and maintenance.
5. Soil and groundwater: In environments with high soil moisture or contaminated groundwater, use corrosion-resistant grades and consider cathodic protection.
6. Polluted urban environments: In areas with high air pollution, stainless steel can corrode due to sulphur dioxide and nitrogen oxides. Use corrosion-resistant grades and consider additional coatings.
Best practices
1. Choose the right grade: Select stainless steel grades suitable for the specific environment.
2. Cleanliness: Regularly clean stainless steel surfaces to prevent contamination.
3. Passivation: Perform passivation treatments to maintain the protective oxide layer.
4. Coatings and linings: Apply additional coatings or linings for extra protection in corrosive environments.
5. Cathodic protection: Use cathodic protection systems to prevent corrosion in harsh environments.
6. Regular inspections: Monitor stainless steel components for signs of corrosion or damage.
By understanding the limitations and taking necessary precautions, stainless steel can be a reliable and environmentally friendly choice for various applications.
About the author: Dr GH Thanki is the former UPL Corrosion Management Advisor; Director and Principal Consultant
Corrosion Control and Monitoring Consultancy; and Principal Corrosion Management Consultant, CorroSafe Consultant.
With over 45 years of experience, he has held senior leadership roles, including as a Corrosion Management Advisor. He led the GSFC Research Centre and served as an advisor to the World Bank and UNESCO. Dr Thanki developed various corrosion combating programs and advised multiple industries globally. He authored over 65 technical papers, guided PhD candidates, and initiated a PG Diploma Course in Corrosion Technology. Recognised with numerous awards, he chaired international conferences and served as a corrosion expert in international arbitration. He has provided consultancy and training in corrosion control worldwide.
