Pneumatic cylinders and hydraulic cylinders are two common components in the mechanical field, both of which have the functions of transmitting energy and converting energy. Although the two seem to be similar, there are still great differences in the operating principle, application field, operation method, and application effect.
1. The principle of operation is different
The principle of operation of the cylinder is to complete the operation by tightening and expanding the gas. When the gas flows into the cylinder, the piston moves forward and then finishes pushing the cylinder. The hydraulic cylinder generally uses oil as the pressure medium, and the operating principle is to push the piston through the pressure transmission of the hydraulic system. In this process, the oil uses static pressure or tangential shear force to transmit the pressure, and then completes the operation of the hydraulic cylinder.
2. Different fields of application
Pneumatic cylinders are generally used in machinery that requires large-scale movement or very repetitive rotation. For example, pneumatic cylinders are often used in mechanical equipment such as drum frames, heaters, glass bending machines, etc. The application scale of hydraulic cylinders is mainly in high-precision, high-load machinery and equipment, such as aviation, military, ships, petrochemical, metallurgy and other fields that need to carry large steel, nuclear power equipment and giant machine tools.
3. The method of operation is different
Pneumatic cylinders are generally a one-way propulsion system, but hydraulic cylinders can provide two-way propulsion and control. The operation method of the hydraulic cylinder is very sensitive, and it can cooperate with other hydraulic control systems to complete the more complex power control. At the same time, the operating speed, strength and angle of the hydraulic cylinder are relatively simple to complete by controlling the flow and pressure of the oil. In contrast, pneumatic cylinders are generally completed by directly controlling the air flow.
4. The effect is different
Since the volume of the oil cannot be compressed, the hydraulic cylinder can withstand high pressure and high load working environment. In addition, in operation, the cushioning function of the hydraulic cylinder is also better than that of the cylinder. Hydraulic cylinders control the speed and force of the oil by controlling the flow and pressure of the oil. These characteristics enable hydraulic cylinders to withstand higher loads, higher precision and remain stable at higher oscillation frequencies. When the cylinder is operating, the function of the cylinder may be affected by different environments even under the same operating load, because the gas is more minimally affected by external influences.
To sum up, there are great differences between cylinders and hydraulic cylinders in terms of operating principles, application fields, operating methods, and application effects. Choosing the working components suitable for your own machinery and equipment can effectively improve the power and reliability of the entire machinery and equipment.
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