What's the difference between hydraulic lifting columns and pneumatic lifting columns?

2,From the perspective of speed and strength:

Hydraulic lifting columns have great strength and can lift heavier columns. Their speed is relatively slow and the lifting is relatively stable. Pneumatic lifting columns are fast but have relatively less strength compared to hydraulic ones.

The working pressure of hydraulic lifting columns is generally around 10 - 35 MPa and can provide a large lifting force. Taking a common lifting column with a diameter of 219mm as an example, a hydraulic lifting column can withstand a weight of up to several tons and is suitable for places that need to prevent the impact of heavy vehicles.

The working pressure of pneumatic lifting columns is usually between 0.4 - 0.8 MPa, and the strength is relatively small. The carrying capacity of a pneumatic lifting column of the same diameter may only be about 1/3 - 1/2 of that of a hydraulic lifting column.

The lifting speed of hydraulic lifting columns is generally slow. The rising speed is approximately 2 - 4 seconds per column (taking a 600mm high lifting column as an example). This is because the flow speed of hydraulic oil is relatively slow, and in the process of controlling the lifting, stability is emphasized.

The rising speed of pneumatic lifting columns can reach 1 - 3 seconds per column. The compressibility of compressed air enables it to quickly push the piston in the cylinder and achieve rapid lifting.

 

3,From the perspective of structure and maintenance:

The hydraulic system has a complex structure, including components such as oil pumps and oil cylinders. Some lifting columns from some manufacturers are not sealed and are prone to hydraulic oil leakage problems, resulting in high maintenance costs. The pneumatic system has a simpler structure, mainly including cylinders and air pipes. The probability of failure is lower and maintenance is easier.

 

4,From the perspective of adaptability to the working environment:

In harsh environments for hydraulic lifting columns, such as large temperature changes and a lot of dust, the performance of hydraulic oil may be affected.

Pneumatic lifting columns are less affected by the environment and can still work well in high temperature, humid and other environments.

In low temperature environments, the viscosity of hydraulic oil in hydraulic lifting columns will increase. For example, when the temperature is lower than -10°C, the fluidity of hydraulic oil becomes significantly worse, which may lead to slow rising of the lifting column or even inability to work normally. In high temperature environments (such as above 60°C), hydraulic oil may oxidize and deteriorate, affecting system performance.

Pneumatic lifting columns are less affected by temperature. Within the ambient temperature range of -20°C to 80°C, their performance is basically stable because the physical properties of compressed air are relatively less affected by temperature changes.

Some hydraulic lifting columns on the market may have contaminated hydraulic oil due to dust and moisture entering if the hydraulic oil pipeline is not well sealed, affecting the normal operation of the system. For example, in an environment with a lot of dust, a poorly sealed hydraulic system may fail within a few months.As long as the air source of pneumatic lifting columns is kept clean, their waterproof and dustproof performance is relatively better. Because the flow of gas can take away some impurities, and the sealing requirements for components such as air pipes are relatively low.