Understanding Compressed Air: Key Principles and Applications

Flow: l/min, m³/h. Pressure: 1 bar = 10⁵ = 1 atm = Pascal = 1 kp/cm². Absolute pressure: Real pressure, including atmospheric pressure. Relative or differential pressure: This takes into account the atmospheric pressure. Temperature: K = 273 ° + °C. Performance: Utilization relationship between the magnitude and extent consumed, expressed in %. Boyle's Law - Mariotte: The volume occupied by a mass of gas at constant temperature is inversely proportional to the supporting pressure. Charles's Law: The volumes occupied by a mass of gas at constant pressure are directly proportional to temperature variations. Gay-Lussac's Law: At constant volume, the pressure of a gas is directly proportional to temperature variations. Combined or General Law: The pressure achieved in a gas is inversely proportional to its volume and directly proportional to its absolute temperature. Venturi Effect: The pressure of a fluid decreases significantly when its speed increases, particularly in a reduced section. Fundamental Properties of Compressed Air: Fluency: Air offers little resistance to displacement. Compressibility: Air can be compressed into a vessel or installation, increasing the pressure. Elasticity: Pressure in compressed air is transmitted with equal intensity in all directions, occupying the entire surrounding volume. Pneumatic Classification: Basic Pneumatics: Study of basic pneumatic components and circuits to command, regulate speed, or control the position of a single actuator. Sequences: The use of pneumatic techniques to perform repetitive movements by chaining multiple actuators automatically. Electropneumatics: When a higher level of complexity is reached, unless the safety of the installation requires the use of purely pneumatic techniques, electric control is used at a more advanced level, often controlled by a PLC. Compressed Air Treatment: Preliminary Filtering: This removes impurities in the form of dust, waste oils, and moisture. Compression: Compressors are used to achieve the proper pressure for use (up to 12 bar in industry). Machines designed to produce compressed air are operated by electric motors or heat. When choosing a type of compressor, two fundamental aspects must be considered: the flow of fluid and the required working pressure. They are classified as: Volumetric: alternative (two-stroke piston, alternative piston), rotary (vane, gear). Turbochargers: radial, axial. Cooling: Compressed air undergoes a cooling process to remove moisture due to high temperatures. Storage: Generally in storage tanks. Maintenance: Air is subjected to maintenance through the so-called FRL unit, which consists of a filter, a pressure regulator, and a lubricator.