A Guide to Pneumatic Systems and Their Basic Components

As aircraft and their respective technologies have continued to advance and grow more complex, an increased amount of power has been needed to efficiently actuate systems and carry out normal operations. Through the use of pressurized fluids such as gases and liquids, power can be transferred throughout an enclosed system to overcome the physical limitations of a human pilot. As such, brakes, doors, landing gear, flight surfaces, and other assemblies may be operated without the sole reliance on pilot strength and mechanical systems. As one of the most popular methods of power transfer, pneumatic systems serve many aircraft for their operations due to their reliability and cost-efficiency.

While the pneumatic system is comparable to the hydraulic system for the operations it can provide, both somewhat differ in the various parts that make them up. As compared to the hydraulic system, pneumatic systems do not feature regulators, reservoirs, accumulators, and other such components that would benefit liquid pressure systems. Despite this, there are some components that may overlap in both systems, often in regard to valves and transportation.

For a pneumatic system to efficiently work and transmit power for actuation, they require air compressors. For some aircraft, air compressors may be used to supply air bottles with pressure, ensuring that there is always enough in the system for actuation. Depending on the amount of force that is needed to carry out a certain procedure, air compressors can provide a number of compression stages so that an optimal value is reached.

With relief valves, the pneumatic system as a whole is protected from an excess amount of pressure. If pressure is allowed to build-up unfettered, lines may begin to burst and seals can blow out. As such, having relief valves in place is crucial for limiting pressure. To achieve this, relief valves will typically have a port that automatically opens as pressure reaches specific values to remove gas as needed.

Control valves are another primary component of a standard pneumatic system, and they are implemented in order to regulate gases. By managing system pressure, the direction of flow, flow rate, and more, a variety of operations may be carried out through the use of control valves and their ports. Within an aircraft, control valves are often used for the operation of systems such as the brakes, as their poppets and ports will efficiently transfer pneumatic pressure to brake lines upon actuation.

In both pneumatic and hydraulic systems, check valves are components that can further dictate the path of pressurized fluids. With a housing containing two ports and a spring-flap on one side, air can push past the flap in order to move in a single direction. If fluids try to move in the opposite direction, the flap will automatically close to impede flow. With this operation, the check valve can serve as a type of one-direction flow control valve.

With standard and variable restrictors, the rate of airflow for operations can be controlled. By forcing air to travel through ports that grow smaller or bigger, airflow can be adjusted as needed to carry out specific tasks. While a standard restrictor may have a set value at which airflow is changed, variable restrictors will often feature components such as an adjustable needle valve in order to manipulate the flow of air as desired.

Due to the fact that pneumatic systems are not always perfectly sealed and airtight, it is important to have filters in place that can remove contaminants and sediment from the assembly. If materials such as dirt are allowed to flow freely, ports and valves can become clogged and the pneumatic system as a whole may fail. As such, filters are put in place throughout the system to impede the flow of contaminants for later removal.

While many aircraft in the modern day may rely on hydraulic systems due to their power capabilities, pneumatic systems present some advantages over their liquid counterparts. For one, pneumatic systems are much lighter in weight, due to the fact that they utilize gases instead of liquids for pressure transferring. Additionally, the system does not need as much piping to conduct operations as gases can be expelled and replaced after their use. Lastly, leaking in pneumatic systems presents less of a hazard for flight as gases may not be flammable like many hydraulic fluids are. As such, pneumatic systems can still present a robust form of power transfer for the actuation of controls and assemblies

With the various parts and components that make up pneumatic systems, compressed air can be harnessed in order to carry out a number of aircraft operations efficiently. When you are in need of valves, filters, compressors, and other pneumatic aircraft parts, look no further than Complete Sourcing Solutions. As a premier distributor for the aviation industry, we provide customers access to a plethora of competitively priced items that have been sourced from top global manufacturers. If there are particular items from our inventory that you wish to procure, you may begin the purchasing process at any time by filling out and submitting an Instant RFQ form as provided through our website.

1. harry walker
2. Posted on January 12, 2021
aviation

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