Written by Lake Engineering Solutions Corrosion Engineer, Dean Kenny
A good supplier of corrosion protection consumables should always evaluate which products or combination of products is the most suited for the intended application. When it comes to corrosion protection, the application of products is just as important as the products selected, and full standard operating procedures must be adhered to in order to give standardisation to the task at hand. In this article we delve into a few of the variables that influence corrosion protection.
Corrosion inhibitor liquids, also known as “Rust Preventatives” (RPs), are available in a wide range of options and formulations. They primarily protect by creating a continuous temporary barrier on the surface of the metal that prevents corrosion.
Typically, RPs are mineral oil or solvent based, however more environmentally aqueous-based or sustainable oil-based products are also on the market today. Volatile Corrosion Inhibitor (VCI) or VpCI® (Vapour Phase Corrosion Inhibitor) packaging products are offered in many options to protect products in various applications, including outdoor use and long-term storage. VCI/ VpCI® packaging is available in polyethylene bags, wraps, film as well as in kraft paper and emitters.
These work by diffusing protective molecules into a sealed enclosure, which are then attracted to the metal’s surface by adsorption. VCIs/ VpCI’s® form a thin, invisible layer that passivates the metal surface and protects it from corrosion. RPs and VCI/ VpCI® packaging can be used together for a comprehensive protection system.
What factors dictate the selection and application of Rust Preventatives?
It cannot be assumed that all corrosion scenarios are the same. Some of the key variables and factors that dictate the selection and application of the VCI/VpCI® RP’s and /or packaging are:
1. Manufacturing Environment
When choosing suitable corrosion protection products the surrounding atmosphere must be taken into consideration. Is the environment clean and dust free or is it contaminated because of the nature of the industry, manufacturing or assembly processes? Temperature and humidity of the environment is also a factor.
2. Standard Processes
Additional stages in a process may result in ‘’bottlenecking’’ if it is a fast-paced environment. The ultimate goal is to reduce steps, this is possible in certain applications by incorporating the corrosion protection into current operating procedures.
3. Employees Safety
The last thing that should be done is introducing a solvent based RP into a confined working space or indoor environment when a safer alternative is available. This will jeopardise employees health if applied without the correct measures and PPE and would lead to a poor working environment. Water-based corrosion RPs have been around for years however they are now establishing themselves as the product of choice over traditional solvent oil-based RPs for indoor, transportation and storage requirements as they are safer to handle and more economical.
4. Length of Protection
For the best product recommendation the length of protection is key as it can vary from a few weeks or months in the precision component industry to years, and even tens of years, for high value assets.
5. Destination of Goods
It is important to know the destination of the goods, items or assets and how they are getting there. Factoring in the environment of the journey is critical in keeping the shipment corrosion free.
6. Specification
Adhering to customer specifications is always the main reason that companies request certain VCI/VpCI® products and how they are applied. This is correct in some instances however specifications can be outdated as new products and better or alternative methodology becomes available. Always work with the end user to suggest a better or alternative method of corrosion protection where applicable, as this often results in a revision of the specification and a better protected product.
7. The Next Stage
If corrosion protection is for the next stage of the process, then it is necessary to ensure that anything that is applied does not create problems in this next stage. Corrosion protection that does not need removal or is easily removable will benefit the next stage significantly.
8. Corporate Responsibilities
Choosing a solution for total corrosion protection that adheres to Corporate Responsibilities statements of the company should always be a consideration when selecting RPs.
For more information on how we can help you with the most suitable and cost-effective corrosion protection for your situation, then please get in contact with one of the team.