Hydraulic power units are driving force behind hydraulic systems. They consist of a motor, a reservoir and a hydraulic pump and generate large amounts of power. Thus enabling them to power any size of hydraulic ram. The most common uses of hydraulic systems are in car braking systems, rescue equipment (Jaws Of Life), lifting equipment, excavation equipment and diggers.
The principle behind hydraulic power units is very simple and involves increasing or decreasing force using pistons. This means a small amount of force is required to produce a large amount of force. The braking system of a car demonstrates the concept perfectly as you only require a gentle push to initiate the brakes. An average car weighs 2.9 tons so the force input ratio allows mere mortals to stop the car with very little effort.
Pascal’s Law is the basis of all hydraulic systems. The law states, ‘that when there is an increase in pressure at any point in a confined fluid, there is an equal increase at every other point in the container’.(Source: grca.nasa.gov). With hydraulics in a car, the force is multiplied and gives the driver superhuman strength.
Pascal’s law is actually very simple especially when you watch it in action. Blaise Pascal was a French mathematician, physicist and religious philosopher in the seventeenth century. He studied the effects of pressure on fluids within a sealed container. He found that an increase in pressure at any point in confined fluid results in an increase in every other part of the container.
Children learn about hydraulic systems using syringes of different sizes. You fill the syringe with water and connect them together using plastic tubing. The system moves model cars, rockets and lifts just by pushing the syringe. You increase power by increasing the size of the pistons (syringes) which is exactly how mechanical systems work. This is a very efficient way of increasing power as long as air bubbles don’t get into the system.
All hydraulic systems work on these principles and have revolutionised the way we live our lives. It is difficult to imagine our lives without them.
Everyday uses of hydraulic power units include; petrol pumps, car braking systems, vehicle repair and maintenance, construction, aeroplanes, amusement park rides, dishwashers, theatres, snowploughs, bakeries and office chairs. They make our lives so much easier it is difficult to imagine how we managed without them.
Hydraulics power units save lives on the road and at sea. The Jaws of Life are hydraulic cutters that cut people out of cars. Lifeboats stations use hydraulic lifting equipment to launch the boat and pull it out of the water. Production lines using robots and lifting equipment increase productivity and relieve humans of heavy lifting. Car braking systems allow us to control heavy cars without significant effort or compromise in design.
If you would like to find out more about our hydraulic power units contact us and we would be pleased to offer advice.