Pneumatic systems are part of many industries. It is part of any process that uses compressed gasses with applications in mining, instrumentation, construction and dentistry. Like hydraulic systems, pneumatic systems also use fluid power. Since these systems deal with compressed air, we need fittings that are air-tight, strong and durable, such as brass pneumatic fittings.
Pneumatic systems are simple to run and efficient. However, to ensure reliability and safety one does have to ensure the right pneumatic fittings. These are parts that connect the parts of pneumatic system, namely the hoses, pipes and tubes. They are required to have a tighter seal than usual hydraulic systems.
A small error in the fittings can cause the entire pneumatic system to collapse. It is often the nuts and bolts that connect various parts that give way and the fault almost always lies in faulty selection or inadequate supervision. So, it’s important that we start right. Here are some of the factors that have to be kept in mind when selecting pneumatic air fittings:
Pneumatic fittings are rated according to the pressure range that they operate in. In most industrial pneumatic systems, working pressure ranges from 80 to 100 psi. It is important that we stick to the range — both the upper and lower limit. Operating above or below the range will cause the eventual failure of the system.
Since they are often an important component of various instrumentation mechanisms, pneumatic systems are found in all kind of applications and environments. This includes environments that can be quite corrosive, such as marine applications and underwater installations. This will obviously require the fittings to be able to withstand the effect of such hostile environments.
This is where brass pneumatic fittings have such a great advantage. Brass is highly resistant to corrosive elements with some types of brass specially designed to withstand seawater or high exposure to other such elements.
Pneumatic fittings also come specified with a temperature range. This is to ensure that these are used only in the right temperature settings. A lower or higher temperature will effect the sealing and eventually cause its failure.
Just as there are many types of pneumatic systems, ether are also different types. These include ball and sleeve fittings, compression fittings, crimp fittings, end fittings, push-to-connect and threaded fittings. Each of these has their own advantages and disadvantages that will suit a particular project. For instance, ball and sleeve fittings are very useful where we need to frequent disconnect and then reconnect, while compression fittings are used whenever we are dealing with considerable compressive force.
Since the entire function of the fitting is to fit into a system, the size is very important. Once you have decided on the types of fitting, the sizing is the most important factor. Sizing is instrumental in ensuring that we have an airtight fit. A wrong-sized part will be completely unsuccessful in forming a tight seal. When undersize or oversize, the fitting will not fix and fail its purpose.
To determine the size of the fitting, we have to measure the size of the part it connects to. Parts like tubes, pipes and hoses have both an outer and inner diameter. These are clearly mentioned as ID (inner diameter) or OD (outer diameter). When selecting a fitting, you have to determine which diameter you will be using, that is whether it will be used at the inner side or the outer diameter. So, a 1 inch OD will require a 1 inch OD fitting.
If you are dealing with threaded fittings, there are multiple sizing requirements that you have to keep in mind. For instance, male and female surface will have their own thread size. The thread size, in turn, is calculated according to the ID of the connecting vessel.
Each fitting is good at performing a certain function. The function of the fitting will determine the particular fitting you need within a type. For instance, fittings which are meant to manipulate pipe lengths include adapters, couplings, unions, caps and plugs. Fittings that are added to change the vessels directions include elbow, tee and cross.
Finally, comes the material. There are many materials available in fittings today, including plastics, composites and metals like aluminium, steel, stainless steel and brass.
Brass pneumatic fittings are a popular choice because these are resistant to corrosion, with good conductivity and ductility in high temperature. Its mach inability makes it a popular choice in compression and threaded pneumatic fittings.