We supply many types of compression fittings, from A-Lok and buttweld pipe fittings from Parker, to sanitary pipe fittings from Bürkert, and high-purity fittings from Parker’s Vacuseal range. We can also supply push-in fittings from Legris and Norgren.
In this article, we’ll address the question of which is best: brass vs stainless steel compression fittings?
What are compression fittings?
Put simply, a compression fitting compresses a component of one fitting into another to create an airtight seal between two different lines. The compression fitting will consist of a sleeve, a nut and the fitting body itself, with the sleeve acting as the seal when the nut compresses it into the fitted body.
Parker provides multiple types of compression fittings to suit any application, from industrial air to fluid transfer. They offer numerous connections, engineered for a variety of tubing with no need for tube preparation, flaring or soldering.
Parker manufactures a wide variety of compression fittings to suit numerous applications and environments, including;
Hydraulic applications
Industrial usage
Nuclear applications
Oil and Gas applications
Pneumatic applications
Subsea applications
Why use a compression fitting?
Compression fittings totally eliminate the need for soldering or welding within a connection. This makes them quicker and simpler to use, with no requirement for special skills or tools. Also, if a fitting is needed in an area that may need to be disassembled over time for maintenance, these fittings can be easily separated and re-attached without any damage to the connection.
Compression fittings do not need soldering or welding. This makes them the ideal fitting for high-heat areas, or places requiring potentially flammable sources. However, they are not as solid as a soldered connection, which means that they may not be suitable for use in an area that is subject to frequent flexing or sudden pressure. This is because they are more sensitive to stress factors.
Read on to find out which is best: brass vs stainless steel.
What are brass compression fittings?
Brass compression fittings from Parker are suitable for a range of pneumatic and medium-pressure hydraulic applications. They are particularly compatible with many industrial fluids. Brass is a copper alloy made with zinc, which gives it added strength and hardness. This makes brass significantly more resistant to corrosion. It also has a higher tensile strength that makes it more resistant to high pressure.
It is important to bear in mind that brass compression fittings are better suited to use with copper tubing, and that stainless steel fittings are used for stainless steel tubing. If you do try to use a brass fitting with stainless steel tubing, you will struggle to obtain a proper seal. This is because the brass isn’t hard enough for the ferrule to bite into the stainless steel tube.
What are stainless steel compression fittings?
Stainless steel compression fittings are designed with high pressures, vacuums and consistent vibration in mind to deliver leak-proof joints. This makes stainless steel compression fittings suitable for almost any environment, particularly pneumatic and hydraulic applications.
Due to the strength and corrosion-resistant properties of stainless steel, this type of compression fitting is particularly well-suited to water hammer and vibration applications, delivering excellent sealing and retention of the tube.
Which is better?
Both brass compression fittings and stainless steel compression fittings have their own benefits. However, one major benefit is that brass is significantly more corrosion-resistant than stainless steel. In terms of thermal and electrical conductivity, brass outmatches stainless steel by fifteen times. Brass also has a significantly higher thermal expansion coefficient, which makes it perfect for applications that involve extremely high temperatures.
For applications that require fluid control of petroleum and highly acidic liquids, stainless steel compression fittings are a better match. Stainless steel has a naturally higher resistance to the acids and chemicals found in these liquids. Finally, stainless steel can also be considered to be far superior to brass in more aggressive marine environments, including fast-moving currents.
