Comparison of advantages and disadvantages between

  • Detail

Comparison of advantages and disadvantages between hydraulic transmission and pneumatic transmission

pneumatic transmission is a fluid transmission that uses compressed gas as the working medium and relies on the pressure of gas to transmit power or information. Hydraulic transmission is a transmission mode that uses liquid as the working medium to transmit energy and control. Hydraulic transmission and pneumatic transmission, known as fluid transmission, is a new technology developed based on the principle of hydrostatic pressure transmission proposed by Pascal in the 17th century. It is a technology widely used in industrial and agricultural production. Both have their own advantages and disadvantages. The following is a detailed analysis of the advantages and disadvantages of both

pneumatic transmission


1) with air as the working medium, the working medium is relatively easy to obtain, and the used air is discharged into the atmosphere, which is convenient for processing. Compared with hydraulic transmission, it is not necessary to set up recycled oil tanks and pipelines

2) because the viscosity of air is very small (about one tenth of the viscosity of hydraulic oil), its loss is also very small, so it is convenient for centralized gas supply and long-distance transmission. Leakage will not pollute the environment as seriously as hydraulic transmission

3) compared with hydraulic transmission, pneumatic transmission has the advantages of rapid action, fast response, simple maintenance, clean working medium and no medium deterioration

4) it has good adaptability to the working environment, especially in the harsh working environment such as flammable, explosive, dusty, strong magnetic, radiation, vibration, etc., which is superior to hydraulic, electronic, electrical control

5) low cost and automatic overload protection


1) due to the compressibility of air, the stability of working speed is slightly poor. However, in order to improve the processing stability, the gas-liquid linkage device will get a satisfactory effect

2) due to the low working pressure (generally 0.31.0mpa) and the structural size should not be too large, the total output should not be greater than 10-40kn

3) the noise is large, and a muffler should be added when exhausting at high speed

4) the transmission speed of pneumatic signal in pneumatic device is slower than that of electron and light within the speed of sound. Therefore, pneumatic control system is not suitable for complex circuits with too many component stages

hydraulic transmission


1) from the perspective of structure, its output power per unit weight and output power per unit size are superior to the others in the four types of transmission modes, with a large torque inertia ratio. Under the condition of transmitting the same power, the hydraulic transmission device has small volume, light weight, small inertia, compact structure and flexible layout

2) in terms of working performance, speed, torque and power can be adjusted steplessly, with fast action response, rapid reversing and speed change, wide speed regulation range, and the speed regulation range can reach 100:l to 2000:1; The action is fast, the control and adjustment are relatively simple, the operation is relatively convenient and labor-saving, and it is convenient to cooperate with the electrical control, as well as the connection with the CPU (computer), which is convenient to realize automation

3) from the perspective of use and maintenance, the self lubrication of components is good, easy to realize overload protection and pressure maintenance, safe and reliable; Components are easy to realize serialization, standardization and generalization

4) all equipment adopting hydraulic technology has good safety and reliability

5) economy: hydraulic technology has strong plasticity and variability, which can increase the flexibility of flexible production, and it is easy to change the production process. The company plans to invest in the construction of lithium battery new energy material projects and adjustments. Relatively speaking, the manufacturing cost of hydraulic components is not high, and the adaptability ratio is strong

6) hydraulic pressure is easy to be combined with new technologies such as microcomputer control to form the "machine electricity hydraulic light" integration, which has become the trend of world development and is convenient to realize digitization


everything is divided into two, and hydraulic transmission is not an example of temperature average:

1) hydraulic transmission inevitably has leakage due to the relative moving surface. At the same time, the oil is not absolutely incompressible. Coupled with the elastic deformation of oil pipes, hydraulic transmission cannot obtain a strict transmission ratio, so it cannot be used in the inline transmission chain of machine tools such as processing threaded gears

2) there are edge loss, local loss and leakage loss in the process of oil flow, and the transmission efficiency is low, which is not suitable for long-distance transmission

3) under high and low temperature conditions, it is difficult to adopt hydraulic transmission

4) in order to prevent oil leakage and meet some performance requirements, the manufacturing accuracy of hydraulic components is required to be high, which brings certain difficulties to use and maintenance

5) failure is not easy to check, especially in units where hydraulic technology is not very popular. This contradiction often hinders the further promotion and application of hydraulic technology. The maintenance of hydraulic equipment needs to rely on experience, and it takes a long time to train hydraulic technicians

Copyright © 2011 JIN SHI