Pneumatic jacks work by way of pressurized gas used to create mechanical motion. Hydraulic jacks, on the other hand, use liquid to affect motion. Both types of jacks are available to consumers; however, hydraulic jacks are more popular for a number of reasons, and pneumatic jacks are less readily available due to the drawbacks of pneumatic mechanics. This doesn’t mean that a pneumatic jack is a bad choice, but rather that a comparison between the two products is time well spent.
Pneumatic jacks have a lifespan of five to 10 years if the jack is properly maintained and serviced as necessary. Hydraulic jacks often last upward of 15 years. The cost of pneumatic jacks, though, is often lower than the cost of hydraulic jacks.
The efficiency and reliability of a hydraulic jack surpasses that of the pneumatic jack. Because pneumatic tools are powered by air, moisture in the air can cause pneumatic tools to freeze up, thereby rendering them inoperable. Furthermore, the air compressor that powers pneumatic tools is often loud and bothersome, which can make the work environment less pleasant. As an example, consider the jack hammer, a pneumatic device that rattles the teeth of pedestrians in cities all over the world.
Pneumatic jacks are also less precise than hydraulic jacks because hydraulic oil, the fluid that is used in hydraulic jacks, is less compressible than gas and therefore can be controlled more precisely. What is more, the higher compressibility of gas decreases the ultimate power that a pneumatic jack can provide.
Beyond the aesthetic and efficiency issues, there is also a greater safety concern with pneumatic jacks. The air hose that connects the air compressor to the pneumatic jack can break free and whip around quite powerfully. This can potentially injure workers.
Astro Air Jack, for example, sells for about $450 and is capable of handling 20 tons. A hydraulic jack by the same maker with the same weight capacity sells for almost $1,800 (in 2009). KSport offers another pneumatic jack specifically made for the quick-change mechanic or pit crew person that sells for $365 (in 2009) and holds 1,210 pounds per jack.
