August 2017

Preventing and controlling corrosion with knowledge and experience

Hello, everyone. Short development timetables make it tempting to commercialize new products or derivative products with no or minimum corrosion testing, sometimes using experience that might or might not include corrosion knowledge.

Experience is often confused with knowledge. Experience is the information acquired from trial-and-error and exposure to different situations. Experience is typically not documented in a database.

Knowledge is based on theoretical frameworks and data and is thus by its nature documented. Corrosion knowledge is typically obtained from:

  • Formal engineering and science education
  • Working with corrosion professionals
  • Corrosion testing
  • Continuing professional corrosion education (training)
  • Professional conferences on corrosion
  • Books and technical papers on corrosion

 

Knowledge without practical experience and experience without theoretical frameworks and data are both incomplete and will not result in useful, predictive professional practice. In other words, experience and knowledge are complementary and when integrated together provide accurate prediction of corrosion for new products and derivative products.

A comprehensive corrosion database contains the knowledge that is integrated with experience. Integrated knowledge and experience are used to assess the probability of corrosion for new products and derivative products, thereby reducing risk. In other words, a comprehensive corrosion database can also shorten the time needed for corrosion testing without the increasing risk.

Two types of information are needed for a corrosion database: numbers and meta data. Meta data is the descriptive information associated with numbers and gives them meaning. For example, pit depths are numbers and the associated meta data could include how the depths were obtained, the chemical composition of the formula that caused the pitting and the spray package component experiencing the pitting corrosion.

Numbers generated with corrosion testing and stored in a comprehensive database could include:

  • Pit depths and blister sizes
  • Corrosion parameters, such as corrosion resistance or estimated container service lifetime
  • Test parameters, such as temperatures and number of replicate samples
  • Test length
  • The percentage of each formula ingredient

 

The corresponding Meta data could include:

  • A unique identifier for each formula
  • A list of raw materials in each formula and the raw material suppliers
  • Specifications for the package components evaluated in the corrosion test

 

A comprehensive corrosion database should also a) be accessible to personnel responsible for spray product development; b) allow easy entry of new corrosion data; c) contain both successful and unsuccessful products and product derivatives; d) list raw materials suspected or known to contribute to or cause spray package corrosion, and; e) list successful and unsuccessful corrosion inhibitors. Maintenance of the database should include:

  • Routine training for new personnel (responsible for spray product development) on how to use the database so that they can access it for guidance on new product development and derivative product development
  • Routine communications to personnel (responsible for spray product development) about changes or enhancements to the database

 

The routine use of a large well maintained corrosion database minimizes repeating mistakes and is a faster-to-market tool. The downside of a corrosion database is that it takes decades to build to where there is enough data to routinely use it for low-risk decisions.

However, database development time could be shortened by backfilling it with corrosion results from all current and past spray products. The data for backfilling could also include actual commercial experience with current and past spray products and their derivatives.

I also recommend that all the corrosion data for a product line be included when it is purchased from another company.

Pair O Docs has a state-of-the art electrochemical corrosion testing laboratory; please contact me if you would like to know more about our faster and predictive corrosion testing. You can also visit our new website which has a short Vision Video that discusses all our corrosion prevention and control services. Please also contact me if you would like to a have our Elements of Spray Package Corrosion short course taught at your R&D facility. Thank you for reading Corrosion Corner and I’ll see you in September.