Dakota Murphey discusses nuanced differences between hydraulic and pneumatic power focusing on its distinct protective measures.
In modern manufacturing, construction and industrial working environments, fluid power systems are vital in powering machinery and equipment. Any type of application is going to incorporate one or both kinds of fluid power alongside electricity – either hydraulic power or pneumatic power.
When implementing protocols and control procedures to ensure safe and continued usage, understanding their operational principles, applications and risk management practices is paramount for guaranteeing workplace safety, whether in construction, manufacturing, medical, logistics, or any other sector.
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Hydraulic systems use incompressible and pressurised liquids – typically oil or water – to transmit power, while pneumatic systems utilise compressed air or gases. These fundamental differences significantly impact their performance characteristics and safety implications.
Pressure switches are essential components in both systems, helping to monitor and regulate operational pressures to prevent potential system failures or dangerous over-pressurisation.
When weighing up either pneumatic or hydraulic systems to deploy, availability of resources, space, cost-effectiveness, products to be moved, and lifting equipment or machinery, are all factors worth considering.
Hydraulic systems can generate significantly higher pressures (1,000-5,000 psi) compared to pneumatic systems (typically 80-100 psi).
The fluids used in pneumatics have lower mass density and are more easily compressed, but such systems may prove incapable of handling larger mechanical force tasks such as the moving or lifting of heavy loads. Comparatively, hydraulics can develop higher levels of pressure which can be transmitted to drive specialised operations.
However, the difference in strength and pressure transmission requires careful consideration of safety elements:
In the interests of minimising emissions as much as possible and maintaining a high level of environmental stewardship, health and safety professionals should consider the following points.
Both systems require electrical power to drive them, with pneumatic systems requiring the continuous running of compression systems to provide compressed air. The air supply cannot be recycled, and pneumatic systems also lose energy through heat production from air compressors.
Comparatively, hydraulic fluids can reuse water or oil after the initial start-up, and provided a reliable filtration system is installed and maintained, they can be very efficient. However, electricity is still required to drive the pump(s) and much of it is wasted due to the fluid medium needing constant circulation to maintain pressure.
In a nutshell:
Hydraulic systems present unique safety challenges due to their use of liquid mediums under high pressure. Key safety considerations include (but are not limited to):
Hydraulic fluids can be prone to leaks, whether it’s hot water, oil, ethylene glycol, plasma or fluid synthetics.
Some of the notable hydraulic system leak risks include:
Hydraulic systems incorporate fewer mechanical parts, but it’s reasonable to expect them to be repaired or replaced on occasion to preserve the system and operational fluidity.
This means that health and safety professionals should:
Hydraulics require high pressure, and occasionally this will need to be properly managed and maintained.
Consider:
Pneumatic systems generally offer more inherent safety features compared to hydraulic systems but still require comprehensive safety protocols.
Compressed air in a concentrated environment can be particularly dangerous and harmful to unprepared personnel.
It’s prudent to:
As with any fluid power system, maintaining pneumatic equipment safety is highly important in any workplace.
This involves:
Health and safety professionals should consider the following strategies when managing fluid power systems in any workplace.
Different industries require tailored safety approaches when it comes to using and maintaining fluid power systems.
Selecting and safely managing fluid power systems requires a solid understanding of their operational characteristics. Health and safety professionals must conduct thorough risk assessments, considering environmental conditions, operational requirements, and potential hazards. The production and testing of these systems is regularly evolving, so it pays off to ensure your facility is equipped with not only the right system(s) but with robust safety protocols that ensure optimal capacity and reliable operation.
The choice between pneumatic and hydraulic systems hinges on specific operational requirements. Pneumatic systems excel in specialised environments demanding cleanliness and precision, but may be less useful in large-scale duties. Hydraulics would be ideal for high-pressure applications like construction or mining, but require more stringent safety controls. The success therefore lies in matching the system to your specific installation context and safety requirements.
Always consult with certified engineering and safety professionals when designing or modifying fluid power systems to ensure compliance with current health and safety regulations.
