Hydraulics are one of the most commonly utilised technologies in sheet metal machinery. This week, we thought we’d take a look at this simple, yet highly effective technology through ten interesting facts.

hydraulic guillotine

  1. Hydraulic systems don’t actually create energy, they simply convert existing energy into another form.
  2. There are three types of hydraulic energy. These are kinetic energy (produced by the moving liquid), the heat energy (produced through flow resistance), and there is also the pressure energy.
  3. Hydraulic systems don’t ‘pull’ the liquid, it is pushed through by air pressure.
  4. Liquid flow must be unrestricted for a hydraulic system to work. If the flow is blocked or has an alternate route, the pressure in the hydraulics will drop and it is this pressure that produces the energy.
  5. Energy used by the hydraulic system is converted not just in the operation of the system but also lost as heat produced by flow resistance.
  6. There are two different types of hydraulic systems: open centre systems which have varied pressure and a constant flow, and closed centre systems which have a varied flow and constant pressure.
  7. In the sheet metal manufacturing industry, hydrostatics is what is used to produce power. This involves using fluids at low speeds but high pressure. The other type of hydraulics is hydrodynamics which uses fluids at high speeds but lower pressure. A propeller is an example of a system which uses hydrodynamics.
  8. Incredibly powerful hydraulics are what is used to power NASA’s space shuttles. The pumps NASA uses have an RPM of 3600, each potentially holding 3050 PSI.
  9. The term hydraulics is derived from the Greek work for water which is hydros
  10. The principles of hydraulics where established as far back as the 17th The first hydraulic presses were commonly used to pump beer up from the cellars up to the bar tap in pubs.


Acra stock an extensive range of new and used sheet metal machinery including hydraulic guillotines. To learn more about our product range and capabilities, please don’t hesitate to get in touch with us by calling 03 9794 6675.