What Is Hydraulic Equipment?
Hydraulic equipment is a device that uses hydraulic pressure to convert or transmit power into motive force.
Specifically, a hydraulic pump is driven by an electric motor or an engine, and the pressure obtained from the pump is used to operate a hydraulic cylinder or a hydraulic motor. Hydraulic equipment provides a large output with a small input, saves space, and has excellent durability against high temperatures.
Because of these features, hydraulic systems are used in a wide range of products, such as large vehicles and industrial machinery, and are products that support industry.
Applications of Hydraulic Equipment
Hydraulic equipment is used in a wide range of applications, from vehicles to machine tools.
1. Vehicle-Related
In the vehicle industry, hydraulic systems are mainly used in large vehicles. This is because they can perform tasks that require large amounts of power with small amounts of power.
- Construction equipment (power shovels, bulldozers, truck lanes, etc.)
- Industrial vehicles (forklifts, concrete mixer trucks, dump trucks, etc.)
- Agricultural machinery (tractors, combine harvesters, etc.)
2. Industrial Machinery
Hydraulic equipment is also utilized in many manufacturing fields.
- Steel manufacturing machinery (pig iron outlet hydraulic drilling machines, etc.)
- Machine tools (lathes, milling machines, drilling machines, machining centers, etc.)
- Drive source for injection molding machines
- Forging machines
- Building vibration isolators (oil dampers, etc.)
- Power generation equipment (Hydraulic equipment for servos, etc.)
- Tunnel boring machines
- Precision gear pumps
- Testing equipment (3D large vibration tables, load testing machines, spring testing machines, etc.)
Principle of Hydraulic Equipment
Hydraulic equipment utilizes Pascal’s Principle, which states that a stationary fluid transmits the same pressure in any direction. Pascal’s principle means that when the cross-sectional area of a pipe is different, the force required to maintain pressure is inversely proportional to the cross-sectional area.
As an example, the following case is explained.
- Pressure: 1.0 MPa
- The cross-sectional area of the input side: 10 cm2
- The cross-sectional area of the output side: 100 cm2
In this case, the following forces are required to maintain the same pressure.
- Force required at input: 100 kg
- Force to be output:1,000kg
As described above, by utilizing Pascal’s principle, a large output can be obtained with a small input. Hydraulic equipment is, of course, also utilized in automobile brakes and hydraulic jacks.
The mechanism of hydraulic equipment is as follows.
- Power from an engine or other source is used to provide rotational force to the hydraulic pump.
- Pressure is generated in the oil discharged from the hydraulic pump.
- The pressurized oil is controlled by the hydraulic equipment and then transmitted to the hydraulic cylinders and motors.
- Hydraulic cylinders and motors convert fluid energy into kinetic energy.
At this point, linear motion can be converted by the hydraulic cylinder and rotational motion can be converted by the hydraulic motor. The oil drained by the hydraulic equipment returns to the oil tank. And when energy is needed again, it is discharged again from the hydraulic pump.
Structure of Hydraulic Equipment
Hydraulic equipment is composed of the following three components, a hydraulic oil tank, pressure gauges and other auxiliary equipment, fittings, and hydraulic hoses.
- Hydraulic Equipment
Hydraulic equipment that generates energy to be added to the oil (mainly the hydraulic pump) - Hydraulic Equipment Hydraulic Drive Equipment
Hydraulic equipment that converts the pressurized oil delivered from the pump into power (hydraulic cylinders, hydraulic motors, vane motors, plunger motors) - Hydraulic Equipment
Hydraulic equipment that controls the pressure and flow rate discharged from the hydraulic pump (relief valve, directional control valve, flow control valve)
In addition, there are four types of hydraulic pumps
- Gear Pump
Pumps that utilize the meshing parts of gears to transport - Vane Pump
Pumps that use several plates to change the volume and transport the fluid. - Piston Pump
A pump that changes the volume of a cylinder by reciprocating a piston to convey. - Screw Pump
Pumps that transport by utilizing the rotation of a screw.
Other Information on Hydraulic Equipment
1. Advantages of Hydraulic Equipment
- Simple structure compared to mechanical or electric
- Compact and powerful force can be obtained
- Can be controlled by simply changing the supply flow rate to the cylinder, so no transmission is required
- The relief valve prevents overloading
- Energy can be stored
- Low vibration
- High-temperature resistance and durability
The appeal of hydraulic equipment is that it can be used in a wide range of environments, including confined spaces and high temperatures.
2. Demerits of Hydraulic Equipment
- Prone to oil leaks and vulnerable to rust and debris
- Need to control hydraulic oil for contamination or deterioration
- Machine efficiency varies depending on the temperature of the hydraulic oil
If hydraulic equipment is to be installed, oil maintenance is essential. To prevent accidents, it is necessary to prepare manuals on inspection frequency and methods.