With reference to an air supply for pneumatic control systems:
(a) state THREE contaminants that may be present;(3)
(b) explain why the contaminants stated in part (a) are undesirable.(7)
With reference to an air supply for pneumatic control systems what contaminants may be present?
In an air supply meant for pneumatic control systems, several contaminants can be present, each posing a potential risk to the system’s performance, reliability, and longevity. Here are the main contaminants that may be found:
1. Clean Air Act: Battling Contaminants in Pneumatic Components – Fluid Power Journal
- Water:
- Source: Atmospheric air naturally contains moisture, which can condense within the compressed air system due to temperature and pressure changes. 1. Understanding Compressed Air Humidity: A Comprehensive Guide – Ceccato www.ceccato.com
- Forms: Water can be present as vapor, liquid droplets, or even ice in colder sections of the system. 1. How Do I Control Contaminants In My Compressed Air System? – JHFOSTER jhfoster.com
- Problems:
- Corrosion: Promotes rust and corrosion in pipes, valves, and other components. 1. How Contaminants In Compressed Air Can Affect Processes | JHFOSTER jhfoster.com
- Freezing: Can cause blockages and malfunctions in cold climates.
- Washing Away Lubricants: Removes lubricants from moving parts, leading to increased wear and tear.
- Contamination: Can carry other contaminants throughout the system. 1. Clean Air Act: Battling Contaminants in Pneumatic Components – Fluid Power Journal fluidpowerjournal.com
- Oil:
- Source: Primarily from the lubricating oil used in oil-lubricated compressors. Even with oil separators, some carry-over into the compressed air is possible.
- Forms: Oil can be present as aerosols, mist, or vapor. 1. Clean Air Act: Battling Contaminants in Pneumatic Components – Fluid Power Journal fluidpowerjournal.com
- Problems:
- Clogging and Sticking: Accumulates in valves and actuators, causing them to stick or malfunction.
- Instrument Interference: Can affect the accuracy and reliability of pneumatic instruments.
- Contamination: Can contaminate products or processes, especially in sensitive applications like food or pharmaceuticals.
- Fire Hazard: In some cases, oil mist can create a flammable atmosphere.
- Particulate Matter:
- Source: Dust, dirt, pollen, rust particles, and other airborne solids drawn in from the atmosphere.
- Forms: Solid particles of varying sizes. 1. Clean Air Act: Battling Contaminants in Pneumatic Components – Fluid Power Journal fluidpowerjournal.com
- Problems:
- Abrasive Wear: Causes wear and tear on valves, seals, and other components, reducing their lifespan.
- Clogging and Blockages: Can clog orifices, filters, and other small passages, disrupting system operation.
- Instrument Malfunction: Can interfere with the operation of sensitive instruments.
- Microorganisms:
- Source: Bacteria, fungi, and other microorganisms can be present in the intake air or thrive in moist environments within the system.
- Problems:
- Contamination: Can contaminate processes or products, especially in hygienic or sterile applications.
- Corrosion: Some microorganisms can contribute to corrosion in the system.
- Health Hazards: Can pose health risks if inhaled, particularly in breathing air systems.
Additional Contaminants:
- Pipe Scale and Rust: From the internal surfaces of pipes and equipment.
- Process Contaminants: Depending on the environment, the air might also pick up contaminants specific to the vessel or its operations, such as chemical fumes or dust from cargo.
Importance of Removal:
- Equipment Protection: Removing contaminants prevents damage, extends the lifespan of components, and ensures reliable operation.
- Process and Product Quality: Clean air is essential for maintaining product quality and preventing contamination in sensitive processes.
- Safety: Removing contaminants minimizes risks to personnel and the environment, particularly in the case of oil and microorganisms.
- Efficiency: Clean air improves system efficiency by reducing friction, preventing blockages, and allowing optimal performance of control equipment.
In summary: Compressed air for control instrumentation needs to be clean and free from contaminants to ensure the safe, reliable, and efficient operation of pneumatic systems on a vessel. Implementing effective filtration and air treatment measures is crucial to achieve the desired air quality.