The operation of pneumatics is comparable to that of hydraulics. Nevertheless, a pneumatic actuator is distinguished by a number of significant differences. As a result, hydraulics and pneumatics are utilized in distinct work environments and carry out different functions.
Fundamentals of pneumatics
Pneumatics is the study of how forces are transmitted through gases that have been compressed. For this purpose, normal air is typically utilized. While this is the case, there are other exceptional circumstances in which nitrogen or inert gasses are utilized as the medium of transmission. Pneumatics, much like hydraulics, works with power amplification by expanding the cross-section of the master and slave cylinders. This is how they accomplish their process. When compared to hydraulics, the medium is the primary distinction. To a large extent, hydraulics is concerned with liquids. One of the characteristics of them is that they are incompressible. Consequently, the proportion of pressure to volume flow remains unchanged throughout the entirety of a hydraulic system. When it comes to pneumatics, compressible gases are used. However, despite the fact that the line cross-section does not change, this causes the operating pressures throughout the entire system to be very varied.
Components in interaction with a pneumatic drive
Pneumatic systems and hydraulic systems share a lot of similarities in terms of their constituent parts. An example of a typical pneumatic system might include the following components:
- Pneumatic drive (pressure generator)
- linear motors
- radial motors
- cables
- valves
Pneumatic systems are designed to be open systems, which is the primary distinction between them and closed hydraulic systems in terms of their architecture. The pressure-transmitted medium is not utilized several times throughout the course of a cycle. Instead, it is drawn in from the surrounding air and then expelled back into the air outside through the different actuators and valves. Because of this, a large number of components that are necessary for a hydraulic system are eliminated. As a result, pneumatic systems either do not require the tank or are far less complicated than other types of systems, which also require elaborate cooling and multi-stage filter systems.
Pressure generation in the pneumatic drive
Additionally known as a pressure generator, the pneumatic drive is designed to function as an electric compressor. For the sake of this function, the following designs have achieved widespread acceptance:
- piston compressors
- compressor
- fans
- screw compressors
The piston compressor
The piston compressor is the typical equipment that is utilized in pneumatic systems for the purpose of producing additional pressure.There is a piston drive that is driven by an electric motor that makes up this device. The surrounding air is drawn in, compressed, and then directed into a storage tank. Following that, the air pressure is delivered to each and every customer through the use of lines.
compressor
Compressors are machines that use a fan wheel that has a specific form. This takes in air from the front and then transfers it to the side side of the vehicle. The employment of compressors in traditional pneumatics is extremely uncommon. The provision of consistent operating pressure for particular operations is the primary function of these devices.
fans
Similar to compressors, fans provide the same function. They make use of a paddle wheel rather than the compressor wheel in their operation.
screw compressors
At present, screw compressors are the only replacement for piston compressors that are available. Rather than being driven by a piston, this particular type of compressor is powered by two compressor spindles that are stacked in a parallel fashion. Classic piston compressors are more expensive, but these newer models are far quieter, more robust, and run more smoothly than their predecessors.
Advantages and disadvantages of a pneumatic drive compared to hydraulics
In comparison to hydraulic systems, pneumatic systems don’t require as much effort to set up and have a far quicker response time. On the other hand, the compressive forces that can be achieved are restricted, and the efficiency of these forces is reduced.
