Oct 07, 2020

Avoiding corrosion of gas equipment: Your options explained

Many gases used in electronics industry and research have toxic or corrosive properties. The gas equipment used must be completely dependable from source to process. There are several options when it comes to extending the lifetime of your equipment while maintaining a high level of performance.
Avoiding corrosion of gas equipment: Your options explained

There are a number of factors that could cause your equipment to corrode – be it external corrosion caused by environmental factors, such as humidity or salty marine conditions, or internal corrosion caused by a reaction between the equipment and the gas. In the latter case, not only does this pose a health and safety risk, but it can ruin the purity of your gas. Having the right protection for your equipment is fundamental. Working with gas companies since almost hundred years, Rotarex has a broad expertise and practical experience to help you find the right solution for your specific application.

Which material?

The first and most important thing to consider is which material is suitable for your application and has the best compatibility with your gas: Brass, stainless steel, aluminum or alloys (Hastelloy®, Monel®, ASB etc.). In addition to a deep understanding of the resistances of each material, Rotarex owns a database listing the compatibility of the different body materials and internal components it offers with 1,081 different fluids.

How can you preserve your equipment and extend its life time?

Once you have selected your material, it could be that you need additional corrosion prevention in the form of a surface coating, treatment or finishing. This may be particularly relevant if the equipment will be used for a specific, unusual application. Rotarex offers the right solution for external and internal protection.

Depending on the body material, a surface coating of nickel, chrome or PTFE, anodization or simply painting can further protect your equipment from external corrosion. Things get trickier if your equipment is at risk from internal corrosion. Here, in addition to the body material, an analysis of internal components resistance must be conducted, to offer the appropriate protection. Surface finishing, for instance, reduces the abrasiveness of each component and improves the gas compatibility, while treatments such as passivation and electropolishing actively protect against corrosive reactions by improving the chromium iron ratio at the surface.

It is sometimes necessary to coat the inside of components, either with an SiO2 or silver coating, or gold or platinum plating. In some cases, Rotarex uses chemical vapor deposition (CVD) to bond the coatings to the surface of the equipment. The process was specially designed for stainless steel, but will also form a thorough, durable coating on alloy that can withstand even extreme temperatures and pressures. In addition to traditional surface coating, Rotarex also offers a special silicon coating on its cylinder valves and equipment. This forms an inert, non-reactive coating that’s ideal if you need consistent sampling and analytical results from your gas.

Whatever your application, Rotarex can help to guide you to the most suitable solution for you, and ensure the optimal performance, safety and longevity of your gas equipment.

Mélissa Cromer
Mélissa Cromer
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