How do hydraulics systems work?

Today's systems include hydraulic components such as actuators, hoses, aqueducts and irrigation systems that deliver water, using gravity to create water pressure. These systems essentially use water's properties to make it deliver itself.

Force multiplication can be created by using a cylinder with a smaller diameter to push a larger piston in a larger cylinder. Often, there will be many pistons.

All types of hydraulic pumps pressurize liquids (typically hydraulic oils), moving a piston through a cylinder and control valves to control the fluid flow rate of oil.

What are the applications for hydraulics systems?

There are numerous applications for hydraulics systems.

Hydraulics are used extensively in the automotive industry for everything from braking systems to power steering. However, they are also used in construction equipment, manufacturing machinery and aircraft.

Hydraulics is so ubiquitous that you probably interact with hydraulics-based systems many times throughout the day without even realizing it.

Examples of hydraulics-based machinery

Now let's look at a few examples of hydraulics-based machinery.

Log splitters

A log splitter is a single-piston hydraulic machine that uses a valve at either end of the cylinder to move the pistons by the pressurized liquid, driving a wedge to force the wood into smaller pieces and return to a home position.

Backhoes

Industrial equipment such as a backhoe often uses several cylinders to move different parts. Electronic controls are generally used for these more complicated setups on large, powerful equipment.

The backhoe's hydraulics system operates the bucket, the dipper arm and the extendable boom.

Bucket trucks

Bucket trucks, also known as cherry pickers, use hydraulics to raise and lower the operator in the bucket to work on high lines or in other elevated areas. The hydraulics system also may be used to rotate the bucket.

As you can see, hydraulics systems have a wide range of applications in many different industries.

Hydraulic Circuits

Transporting liquid through a set of interconnected discrete components, a hydraulic circuit is a system that can control where fluid flows (such as thermodynamic systems), as well as control fluid pressure (such as hydraulic amplifiers).

The system of a hydraulic circuit works similar to electric circuit theory, using linear and discrete elements. Hydraulic circuits are often applied in chemical processing (flow systems).

Hydraulic Pumps

Mechanical power is converted into hydraulic energy using the flow and pressure of a hydraulic pump. Hydraulic pumps operate by creating a vacuum at a pump inlet, forcing liquid from a reservoir into an inlet line, and to the pump. Mechanical action sends the liquid to the pump outlet, and as it does, forces it into the hydraulic system.

Hydraulic Motors

The conversion of hydraulic pressure and flow into torque (or a twisting force) and then rotation is the function of a hydraulic motor, which is a mechanical actuator.

The use of these is quite adaptable. Along with hydraulic cylinders and hydraulic pumps, hydraulic motors can be united in a hydraulic drive system. Combined with hydraulic pumps, the hydraulic motors can create hydraulic transmissions. While some hydraulic motors run on water, the majority in today’s business operations are powered by hydraulic fluid, as the ones in your business likely are.

Hydraulic Cylinders

A hydraulic cylinder is a mechanism that converts energy stored in the hydraulic fluid into a force used to move the cylinder in a linear direction. It too has many applications and can be either single acting or double acting. As part of the complete hydraulic system, the cylinders initiate the pressure of the fluid, the flow of which is regulated by a hydraulic motor.

Hydraulic Energy and Safety

Hydraulics present a set of hazards to be aware of, and for that reason safety training is required.

For example, this short sample from our online hydraulic safety training course explains some of the ways the fluids in a hydraulic system can be hazardous.

Remember, the purpose of hydraulic systems is to create motion or force. It’s a power source, generating energy.

Don’t underestimate hydraulic energy in your safety program. It is small but mighty in force. And like any force, it can do great good or great harm.

In the workplace, that translates to a potential hazard source, especially if uncontrolled. Hydraulic energy is subject to OSHA’s Lockout/Tagout rules, along with electrical energy and other similar hazard sources. Be sure to train workers about the hazards of uncontrolled hydraulic energy, especially during maintenance, and the need for lockout/tagout, as illustrated by this still image from one of our online lockout/tagout training courses.

Also, workers need training which must explain the hazard potential and clearly detail methods to prevent injury. According to OSHA:

“All employees who are authorized to lockout machines or equipment and perform the service and maintenance operations need to be trained in recognition of applicable hazardous energy sources in the workplace, the type and magnitude of energy found in the workplace, and the means and methods of isolating and/or controlling the energy.”

 

Conclusion: Hydraulics Are Common in the Modern Workplace

Having a working understanding of hydraulics of the type we've covered in this article will help you better understand a modern workplace and will make you or your company more efficient, productive, and safe.