Nowadays, pneumatic and hydraulic systems have become very common because of their wide applications in industrial operations. In most cases, they are used for holding, lifting, gripping, and drilling operations. They transmit power via fluid or air pressure, with fluids coming from the reservoir through a pump or air from an air compressor. So, if you have a new facility and are considering using a pneumatic or hydraulic system, one question that you need to address is, "Which one do you select?" 

To help you make an informed decision, this post provides answers to common questions on hydraulics and pneumatics. 

What is the Main Difference Between Hydraulic and Pneumatic Systems?

Although pneumatic and hydraulic systems use the same principles of motion, the results are achieved in different ways. 

For the hydraulic system, the main medium used for power transmission is a hydraulic fluid, which runs from the reservoir and is then pumped to actuators by a pump. Common applications that use hydraulic applications are car jacks, bulldozers and garbage trucks. Pneumatics, on the other hand, uses compressed air from a compressor and is finally directed to actuators via hoses. Common applications of pneumatics include material handling, packaging, and drilling equipment. 

What are the Main Components of a Hydraulic and Pneumatic System?

Because they use pressure, either pushed through pressured gas (pneumatics) or hydraulic liquid (hydraulic system), they share a number of things. Here are the common parts that you will get both in a hydraulic and pneumatic system: 

• Pumps which are used to push either liquid hydraulic through the hoses or gas to the actuators. 
• Pressure regulators, which help to regulate the pressure of either liquid or air on the system. 
• Control valves. These are used to manipulate the flow of hydraulic fluid or gas in a pneumatic system.

What are the Two Categories of Hydraulic Systems?

If you opt for a hydraulic system, it is important to appreciate that it falls into two main categories, the open center and the closed center system. 

In an open center system, the fluid is pushed to the actuator and then directed to a reservoir through a central passage using a directional control valve. When a directional valve's spool is hit, the flow is directed towards a selected load and pressure generated. If the pressure exceeds the load, the load starts moving, and the targeted action is executed. 

On the other hand, a closed center hydraulic system only generates enough flow to keep the pump lubricated and reach the standby pressure at the control valve. When the spool of the directional valve is stroked, it exposes a passage for the flow to enter as a pressure signal is sent to the pump. It is this signal that prompts the pump to start producing flow that runs the actuator.

What are the Advantages of Pneumatic vs. Hydraulic Systems?

Notably, both hydraulic and pneumatics come with their own benefits, and it is important to understand them before making your decision. Hydraulic systems are easy to control, accurate, and simple to maintain. For example, you can easily control operations using levers and buttons to do your work. However, they are prone to leakages, which can make a mess of your workplace. 

If you prefer pneumatic systems, they can be pretty enjoyable to use because of the low friction, and enhanced safety compared to the hydraulic system. Also, there is no risk of suffering a messed up work area. However, controlling pneumatics can be challenging and requires a lot of air to be moved rapidly. 

So, which one do you pick? To select the preferred option between hydraulic and pneumatic systems, it is important to factor in the targeted application and the benefits we have listed above. You might also want to work with an expert for a more detailed review of each system in line with your production targets.