There are many different types of presses used in industrial settings for pressing and forming of many materials. There are many different types of presses, from the benchtop pneumatic press to the hydropneumatic press. Pneumatic presses and hydraulic presses are two of the most popular because they’re similar in function. The question is when to choose an air press machine and when to choose a hydraulic press. Here is everything you need to know about the differences and what to think about when choosing.
Understanding the Hydraulic Press
Hydraulic presses at their most basic are chambers filled with a liquid, typically oil. A piston is used to move the oil about inside the chamber. The chamber is sealed, so the oil that is pressed by the piston is forced to put pressure on another larger piston or on a baseplate. The plate or piston then exerts downward pressure.
Understanding the Air Press Machine
The air press machine, as the name suggests, is controlled by the use of pressurized air. Highly pressurized air is forced into a tube. This tube, once filled with air, then applies pressure in turn on the baseplate. Once the stroke has been finished, the air leaves through a series of valves and a mechanical spring allows the pump to come back up.
Hydraulic Press Pros
The hydraulic press is extremely strong and very dependable. It also moves quite slowly, which makes it ideal for hydroforming, where the metal needs time to be shaped properly.
Hydraulic Press Cons
A hydraulic press will require a lot of maintenance; more maintenance than an air press machine. A hydraulic press’ oil needs to provide constant pressure, so there are many auxiliary devices attached to the press to monitor and regulate oil pressure. The more devices you have, the more opportunity for a failure.
Air Press Machine Pros
A pneumatic press is capable of moving at great speed. In fact, pneumatic presses can move as much as 10 times faster than a hydraulic press. Another advantage of a pneumatic press is that it can be stopped at any time. Pneumatic presses are also versatile and come in many styles, including a pneumatic hand press. They can even be installed upside down. The air press machine is easy to use, has few moving parts, has no fluid and therefore no opportunity for leakage, and is in general very durable and dependable.
Air Press Machine Cons
The primary negative when it comes to an air press machine is that most are not capable of exerting the same enormous amounts of pressure the hydraulic press can generate. Furthermore, its great speed makes it less useful for certain applications where the item being pressed or formed needs time to be shaped precisely.
When to Choose Which
Both a hydraulic press and air press machine can be used in many of the same applications and will produce the same quality of end result. Both can normally be adjusted so that both the pressure and the length of the stroke can be adapted to specific need. They’re both generally preferable to any sort of mechanical press, because they have full tonnage at any position along the stroke. The first reason to choose one over the other is speed and tonnage. Pneumatic presses are faster, meaning that in some jobs they will be far more efficient. Hydraulic presses are much better for hydroforming or other processes they require a slower speed. Otherwise, the main difference between them comes down to maintenance. Hydraulic presses will require more maintenance and are more complicated.
Both an air press machine and a hydraulic press are useful in many applications for pressing and forming. The main decision to make between them is whether you have a specific need for the power and precision of the hydraulic press, or a specific need for the speed and efficiency of the pneumatic press. If neither of these considerations is applicable and either press could be used equally well, the pneumatic press is to be preferred because of its easy maintenance.