What is a Hydraulic Fluid Power System?

Hydraulic fluid power systems are in wide use in industrial applications. The natural flow of pressurized fluid is used to supply energy to a hydraulic system. Thisis based on the concept of

Pascal’s Law which states that enclosed fluid under pressure exerts that pressure equally in all directions.There are many reasons why hydraulic systems have become so popular for use in industry. Certainly, a key reason behind the adoption of hydraulic systems is their ability to provide consistent, significant power to repetitive tasks.

Originally, these systems worked with water, and that is how the term hydraulic came to be associated with these systems. However, over time, the systems were altered to work efficiently with oil-based fluids.

A hydraulic system is based on drive technology in which a hydraulic motor is utilized to deliver the hydraulic fluid, and its associated power, to an actuator (an actuator is a specialized system component that controls movement in a hydraulic system).

When force is applied in a sealed system, the piston pushes through the cylinder to displace the fluid and magnify the force. A hydraulic fluid system generates a significant amount of force even when a small amount of external force is applied to it. There are applications that need a specific amount of rigidity that can only be provided by a liquid. A hydraulic cylinder works best in such situations. The motors and cylinders used in a hydraulic fluid system are small in size but have an exceptionally high energy potential. Since they can fit in small spaces, they suit all sorts of applications.

Hydraulic System Components:

Hydraulic Pump

Hydraulic pumps perform the task of converting mechanical energy into hydraulic power by controlling the flow and pressure of the hydraulic fluid. There are two main roles that hydraulic pumps perform. The first role of a hydraulic pump is to draw the hydraulic fluid through an inlet from the hydraulic fluid reservoir into the hydraulic pump. To accomplish this, the pump creates a vacuum that draws the fluid through the inlet port.

Secondly, hydraulic pumps by their mechanical operation force hydraulic fluid to a pump outlet and into the hydraulic system itself.

Once the hydraulic pump has forced hydraulic fluid into the hydraulic system, it continues to generate fluid flow. An important point to note is that the pump itself does not create pressure. Pressure generation is accomplished by impeding the flow of fluid within the overall system.

Hydraulic Motors

So, what exactly is the difference between a hydraulic pump and a hydraulic motor? One way to explain this difference is to consider the tasks that they perform. A hydraulic pump will be connected to an electric motor and, as noted above, serves to generate hydraulic fluid flow within the hydraulic system. In contrast, hydraulic motors take the fluid pushed along by the pump and create rotational motion leading to torque and the power required to undertake the desired mechanical action.

There are three different types of hydraulic motors. Each of these motors has specific traits that make them suited to different situations. Gear motors deliver medium pressure levels at a lower cost than the other motor alternatives. Vane motors come with a higher cost than gear motors while also delivering a higher flow rate. Regardingcost, piston motors are the most expensive of the three motor types. Piston motors also deliver higher pressures and flow rates.

More information on these different hydraulic motor types is provided below:

  1. Gear Motors
  2. Gear motors make use of a two gear system. One gear is a driver gear which is connected to the output shaft while the second gear is an idler gear. Gear motors are considered high-speed motors, however, they do have the capability of reducing their speed by making use of their gearing system.

    Gear motors have benefits and weaknesses. One of the weaknesses is that the noise level created by these motors can be significant. Additionally, fluid leakage can occur in these motors which can reduce their efficiency. Gear motors do provide benefits in terms oflower costs and more dependable operation.

  3. Vane Motors
  4. As opposed to gear motors, vane motors change speeds without the use of gears. Vane motors make use of an electric bore to control the rotors and generate medium level pressures. Vane motors are typically quieter and more efficient than the gear motors discussed previously. Vane motors also represent an economical alternative to piston motors.

  5. Piston Motors
  6. Hydraulic piston motors do come in at the high end of the cost scale as noted above. This is in large part, however, due to their higher performance capability forcreating higher pressures and fluid flow rates. Piston motors come in a variety of designs including axial and radial types.

    An axial piston pumpis constructed of a number of pistons positioned in a circular design within a housing, or cylinder block. The cylinder block rotates around its axis. Axial based piston motors may be further categorized as either in-line-axis or bent-axis types.

    Radial piston motors are fixed displacement pumps meaning they deliver a constant rate of flow. They come in two basic types depending on the pushing direction of the pistons either inward or outward. Radial piston motors have a unique capability to develop high levels of torque at low speeds.

Hydraulic Cylinder

A hydraulic cylinder is a mechanical device that contains hydraulic fluid that when put under pressure creates unidirectional power. As part of an overall hydraulic system, the cylinders start the hydraulic fluid compression which is in turn managed by the hydraulic motor.

more frequently utilized in simpler applications and hence are generally less sturdy in their design.

As a result of these hydraulic systems components, machines that operate based on a hydraulic system are easily adjustable and at the same time, exhibit stability. They can be programmed for accurate acceleration and sudden stopping. Thus, they are perfectly suited to be used in situations when sudden momentum creation is required. Another advantage of using a hydraulic system is that it can handle high torque and rapidly changing speeds easily. The power is distributed evenly in all directions in a hydraulic system making it easily maneuverable. Hydraulic systems can work efficiently in challenging environments as well. These include working underwater and working with exposure to open flames or extensive heat. The best thing about a hydraulic system is that it requires a minimal amount of maintenance. Hydraulic fluid power systems are being used in all types of industries including construction, manufacturing, exploration, and many more.

Seaway Fluid Power (SFP), was established in 1976. Based in St. Catherines, Ontario, SFPG provides its customers with quality fluid power products and services. SFPG carries an extensive parts inventory of fluid power products such as hydraulics, pneumatics, hose and fittings, stainless steel fittings, instrumentation and compressed air.

"When there’s no time for downtime."

Sea Way Fluid Power Group