What Are Pneumatic Fittings Used For?
Pneumatic fittings are parts that are used to connect sections of tube, pipe and hose in pressurized gas systems. Unlike hydraulic fittings, pneumatic fittings have lower pressure requirements and tighter seals. Different types of vessels require different types of fittings. Hoses require fittings that are not permanent because a hose is replaced when it is worn. Unlike hoses which are flexible, pipes are rigid and made out of solid material. Tubes are defined by their outside diameter dimensions. They are also rigid and made from solid materials.
Pneumatic fittings are distinguished by the function it performs. They are attached by a different number of connection methods. Ball and sleeve fittings are ideal for applications that require frequent disconnection and reconnection. They connect an inner ball fitting to an outer sleeve. Compression fittings use metal gaskets, ferrules and rings to form a seal on the vessel through compression. Bite style fittings bite the vessel when it is compressed providing the seal. They give you a stronger pressure connection. Flared fittings have a flared or coned end. They can handle a wider range of operating applications and handle higher pressures. Placing a hose over a tubular end crimping it against ring, sleeve or crimp socket is called crimp fitting. Push-to-connect fittings disconnect from a type of collar retraction. This is also an ideal fitting for systems that frequently disconnect and connect. Threaded fittings have screw heads on both their inner and outer services. They are designed to accept matching thread connections. These threads are in important because they provide a “dry fit” which helps prevent corrosion and contamination.
There are a variety of types of fittings found in pneumatic systems that perform different functions. The adapter and coupling connect two pipes together by either soldering, threading or solvent welding. The cap covers the end of the section and attaches around the pipe via a weld. The plug attaches inside the pipe and closes off the flow at the end of a section. There are also pneumatic fittings that change or add direction. An elbow fitting changes the flow to different angles. A tee fitting allows fluid flow to be split apart in t-shaped intersection. A 4-way connection that provides three outlets and one inlet is a cross fitting. A standard nipple connects two separate fittings to each other.
Once you have determined the proper fitting you will need to determine the proper sizing. If you choose a fitting that is not properly sized, it will connect and seal inadequately. To determine the size of the pneumatic fitting, you will need to size the vessel it is being connected to. The fitting material is an important factor when it comes to pneumatic fittings. They can either be plastics, composites or metals. Metals can be aluminum which is lightweight and corrosion resistant. Brass is also very strong and is the most common metal used for smaller threaded fitting. It has excellent performance abilities and machinability. Steel has a high resistance to heat and an alloy of iron and carbon. Stainless steel is chemical and corrosion resistant. Stainless steel has the same strength and durability as steel. Plastics are used for temperature requirements above 500 degrees F. They have proven to be excellent in resisting dielectric properties and chemicals. Composite fittings are made from graphite, carbon and fiberglass. The materials in these fittings have high melting points and work well in high temperatures.