Compressed air is a vital source of power in modern day automation and industrial assembly. However, despite the tremendous advantages and vast potential of this technology, many myths surrounding air compressors persist. Some of these myths are based on misunderstandings about what can and cannot be accomplished with pneumatic tools. Others are derived from outrageous claims made about certain machines and system components. In any case, compressed air myths have confused and even dissuaded people in certain sectors who could otherwise benefit immensely from this great power source. The 14 following misperceptions are among the most widely circulated compressed air myths.
Myth #1: Compressed air is safe to use for cleaning dust and dirt from work spaces.
Truth: Air compressors don’t suck up air, they send it outward from high–pressure applications. Therefore, compressed air won’t make dirt particles disappear across floors, tables and other surfaces, it will only redistribute them. Even worse, compressed air could send dirt particles in all the wrong directions.
Myth #2: In order to make the best of part–load performance, the most optimal solution is a variable–speed drive.
Truth: Generally, this is not the case. Due to the way that they’re made, variable–speed compressors run best within a certain range. Therefore, if the demands of a particular load call for faster or slower speeds, it’s best to choose different control options. If you plan to use an air compressor for a lot of different applications, it’s always best to ask a knowledgeable dealer about which type of machine would best suit your operations.
Myth #3: Oil carryover is accelerated in variable speed drives.
Truth: Running at lower rates probably won’t have any negative effect on the carryover of oil. The lowered flow of air will reduce the speed in the separator, which will make things more efficient. Boosted carryover is aided by two main factors: heat and low pressure, neither of which results from variable speed drives.
Myth #4: Flow controllers are unnecessary on air compressors with variable–speed drives.
Truth: While applications run the gamut, most systems work best with the added stability and pressure consistency of a flow controller. These can even benefit the most optimal systems already using a VSD air compressor.
Myth #5: Synthetic air compressor fluids are all identical.
Truth: Synthetic fluids have one basic thing in common: they’re not made of hydrocarbon base stock. Beyond that, a synthetic fluid could consist of any given number of formulations. Some of the most common synthetic fluids are made of PAG and PAO base stocks, which differ significantly in terms of their effects on the performance of an air compressor. In order to know whether a synthetic fluid will be right for your system, it’s important to know the base stock and the kind of effects it would have on your air compressor.
Myth #6: All polyglycol (PAG) compressor fluids are made with the same formulations.
Truth: PAG fluids fall into two categories: those formulated in combination with expensive, high–grade polyolesters, and those mixed with cheaper, lower–grade diesters. POEs are high–cost fluids that are valued for their impeccable, heat–resistant and sludge–free performance, which generally makes them the best option for demanding applications in rotary screw compressors. Diesters are a low–cost fluid type that’s notorious for allowing sludge buildup in air compressors. Consequently, the money that an operator might save by using diesters could ultimately be wasted on costly maintenance issues due to the presence of sludge, which can be hard to remove in an air compressor. Other problems associated with diesters include swollen gaskets, leaks, eroded shaft seals and inflated hose liners.
Myth #7: Aftermarket replacement parts are just as good as original parts sold by the manufacturer.
Truth: If a part is designed for a particular machine by the manufacturer, it was done so with concern for performance and reliability. Understandably, the manufacturer is best equipped to design parts that meet the needs of specific machines and operations. Aftermarket makers, on the other hand, mostly make parts for a more generalized usage that won’t necessarily account for the nuances of your air compressor.
Myth #8: Compressed air is generally impure.
Truth: Contrary to common perception, compressed air is mostly clean. While the air produced in older systems can sometimes be dirty, this is usually an issue of poor maintenance, and not just an inherent quality of the machinery.
Myth #9: Compressed air is more expensive than electrical power.
Truth: Not if it’s used efficiently. Compressed air is made for a range of applications that generally require high power. In most of these applications, pneumatic tools are capable of delivering the power needed, with far greater speed and efficiency than anything that runs on electricity or batteries. “Efficiency” is the operative word here, because in applications where compressed air gets wasted, the financial advantages are drastically reduced.
Myth #10: It’s best to store air compressors in the same room as HVAC units.
Truth: While it might seem practical to store all air–based machinery in the same room, an air compressor works best within natural room temperatures. In the immediate presence of HVAC units, temperatures can skew to unnaturally hot or cold extremes, depending on the needs of the building in question. For an air compressor, harsh temperatures can lead to issues such as condensation and mold growth.
Myth #11: Gravity–based oil/water separators are always best for compressed air systems.
Truth: Despite their ubiquity, gravity–based separators are not the only option when it comes to separating oil from water in an air compressor. They can be difficult to work with and hard to maintain properly; and they can also cause germs and lead to costly repair bills. For all these reasons and more, the switch is on to molecular filtration systems that separate wastewater from lubricants. Functioning without pumps or filter pads, molecular filters use media beds to trap impurities from passing water. Afterwards, the water is rendered clean enough to pass down a standard facility drain.
Myth #12: With increased pressure comes a higher operating cost.
Truth: On one hand, it does take more energy to compress a cubic foot of air to a higher pressure. However, the whole system would have to be run with greater intensity before energy bills would rise. Flow is key.
Myth #13: Patching up a few air leaks is better than nothing at all.
Truth: If power is being lost due to supporting a number of tiny air leaks, efficiency can only be regained with thorough repairs. Without a pressure–control device in place, an incomplete round of repairs can actually end up wasting more energy, because as the volumes of pressure increase, and with greater flow more air is ultimately leaked through the holes that remain.
Myth #14: Greater system–wide pressure raises productivity.
Truth: In large scale productions, pressure needs are most efficiently handled at the localized level. The amount of pressure called upon for one application might be excessive for neighboring stops along the conveyer belt. With compressed air systems, energy is best put to use when pressure levels are raised and lowered for specific applications, as opposed to being set a maximum centralized levels.