Gaskets: key selection criteria

Gaskets are used for a wide variety of applications in every industry. Gaskets are vital for reliable and efficient production. The huge variety of materials, shapes and sizes offers an infinite scope of application possibilities. A clear selection process helps you purchase the right gaskets for your production environment.

Despite their often small size and 'invisible' role in the production process, gaskets are crucial. Selecting the right gaskets is, therefore, very important. A wrong choice can have major consequences. In the design phase of a machine or component, this can mean extra work, higher costs and longer time-to-market. With ongoing processes, there is a risk of leakages, errors in production or even accidents with far-reaching consequences. High-quality gaskets increase workplace safety and allow machines and components to function better and last longer. All this can lead to a more efficient production process and a significant reduction in downtime.

That sounds reassuring. But when you realise that, due to all the possible variations, there are tens of thousands of different gaskets available, a structured selection process becomes an absolute necessity. Meticulous preparation is an essential first step. Before making the final selection, it is advisable to answer the following questions with detailed information from the client:

• In which application will the gasket be used? What role does this application play in the production process? And what environmental factors does this application have to deal with? By accurately describing the production process, it is also easier to determine later in the selection process the special properties required of your gaskets.
• What requirements must the gasket satisfy to meet the applicable production standards at your manufacturing location? Consider the minimum requirements for safety and quality. Available documentation and the traceability of utilised materials play an essential role in this evaluation.
• How long must the gasket last?
• Does the application allow standardisation, or is customisation required? Gaskets are ideal for standardisation, so consider rationalising the number of types and types. They can also be fully customised if required.

Gaskets are exposed to various production factors during the manufacturing process. These factors determine the minimum requirements and properties your gaskets must have. Medium, pressure and temperature are the most important of these. To select the right gasket for your application, you need to know exactly what conditions your production process is subjected to. The right gasket will not only withstand each production factor individually, but also perform at its best when the three are combined.

One of the most important selection criteria is that every component in a gasket must be chemically resistant to all media it comes into contact with. Not every gasket material is suited for exposure to certain liquids, solids or gases. In such cases, the gasket material might wear faster, for example, or show higher permeability. It is, therefore, important to assess the gasket's resistance to each individual medium. Please note that when two or more media are combined during the production process, this may require a new resistance level and different gasket material.

The right gasket must not only be resistant to the media passing through the device or pipes during the production process, cleaning agents, lubricants and other media in close proximity to the application should also be considered in the selection process.

In production environments, it is quite common for pressures within an application to rise quickly and significantly. Not all gaskets can withstand this. A gasket that malfunctions under high pressure can create life-threatening situations. It is, therefore, imperative to know precisely how high the pressure can rise, and just as important is to estimate how often and how long the gasket has to operate under that pressure. The pressure level in the application largely determines the material from which the gasket should be made.