Built almost like an automotive engine, reciprocating compressors have a crankshaft driven by an electric motor. As the shaft turns, it pushes a piston up and down, drawing air into a chamber as it moves in one direction, then compressing it when the piston reverses direction.
For more information, please visit NAILI.
Often called piston compressors because of their construction, reciprocating compressors are very practical for small applications. They are rugged and durable, holding up well when properly sized. Unfortunately, they need to be oversized, because they have a low-duty cycle, needing time to cool off. Heavy use or a high-duty cycle is not recommended. Single-stage models have only one compression chamber and come in sizes from .25 to 5 HP. They are better for low-pressure applications.
Recips are also available in a multi-stage design that uses more than one stage to compress air to the final discharge pressure. Multiple cylinders each perform a different stage of compression. An interstage cooling device reduces the air temperature between the stages of compression, decreasing the work required and the risk of mechanical failure due to excessive heat. Multi-stage compression is more energy-efficient than single-stage compression for high-pressure applications.
Double-acting reciprocating compressors have compression chambers on both sides of the piston and can get much larger, up to 1,000 HP. But while double-acting reciprocating compressors have water cooling that addresses the duty cycle issues, they are becoming less common because they are expensive, require reinforced foundations to handle vibration, and need more extensive maintenance.
Most recipes in use in industrial applications today are two-stage compressors, which are much more durable and can deliver greater pressure and flow, according to Air Compressor Guide.
As mentioned above, reciprocating compressors have a limited duty cycle, working best with intermittent or partial duty. They typically run best at 50% duty cycle or less. That&#;s 30 minutes in an hour. Run it longer, and you risk damaging your compressor and shortening its life. As a result, to properly size a recip, you need to consider a compressor with a larger horsepower rating to give the pump time to cool down.
Pistons produce larger air pulses than rotary screws. And, because they just have wiper rings between the air and the oil, they do not have systems in place to prevent oil slugs from passing through. Those are huge disadvantages for painting applications where you want a smooth, even flow of high-quality air to produce the mirror finish your customers want.
And they are noisy. Because pistons are generally open, with loud valves and no acoustical enclosures, reciprocating compressors are noisy, with sound levels usually over 85 dBA, requiring hearing protection mandated by OSHA. In fact, many companies want to isolate them in rooms that become hot and stuffy. Or move up to rotary screw air compressors to reduce the noise and vibration.
Table of contents
Air compressors can revolutionize how your operations function, leading your business to get more work done at a higher level of quality. However, there are two primary types of air compressors on the market, and it can be challenging to determine which one you need.
If you're trying to decide between a lubricated or oil-free air compressor, we can help you determine which is best for your application. Below, you'll find information about these air compressors and the pros and cons of each.
Air compressors utilize a piston or rotary component that draws in air, which is compressed into a storage tank. Rotary elements and pistons need to move smoothly and consistently, which is why these parts generally require lubrication.
Lubricated air compressors, or oil-flooded air compressors, use oil to lubricate moving parts within the system. Lubricating oil is required for lubricated air compressors to ensure the piston or rotary element runs smoothly without damaging the equipment. The lubricating oil also helps maintain the efficiency of air compression and dissipates heat.
Unlike lubricated air compressors, oil-free air compressors utilize pre-lubricated materials, like Teflon, to coat their compression elements instead of oil. Some oil-free compressors may also use water instead of oil for the lubricating and cooling process. Even without oil, these materials pre-lubricated materials or water can help mechanisms move smoothly within the air compressor.
These air compressors also require rotors that have tight mechanical tolerances, which helps reduce friction between the components. Remembering that &#;oil-free&#; only refers to the compression chamber is essential. Lubrication may still be needed for parts outside the compression chamber and bearings.
The differences between oilless and oiled air compressors are vast, even beyond the presence or absence of oil. Explore the advantages and disadvantages of oiled and oil-free air compressors in several key areas, from size to air quality.
Oil-free compressors tend to be smaller than lubricated air compressors because they don't need additional room for oil. As a result, oil-free compressors also tend to be more portable. If you need an air compressor to move around your worksite, an oil-free option may be best suited to your applications.
For more information, please visit air cooled oil free air compressor.
Lubricated air compressors are best suited to warm climates. These temperatures help ensure the oil inside the components continue running smoothly. Alternatively, oil-free compressors are better suited to cooler climates, where lubricated air compressors can't perform at peak efficiency.
You may choose between one type of air compressor over the other if you're working in extreme temperatures.
Oil-free air compressors may be the better choice if you follow these strict guidelines because the air in lubricated air compressors can become contaminated by the oil. These air contamination concerns aren't relevant in all industries, but some must follow air quality guidelines, such as the food processing, electronics and pharmaceutical industries.
Noise emissions may be a significant consideration for your business, especially if noise can disrupt your operations. Lubricated air compressors typically make less noise because of the oil they use. If noise isn't a concern, you can choose between lubricated or oil-free air compressors, depending on the other requirements of your applications.
Because lubricated air compressors need to move oil throughout the compression chamber and bearings, these machines tend to use more energy than oil-free air compressors. Oil-free compressors can help minimize your energy usage, which helps reduce your environmental impact and overall costs.
Lubricated air compressors have higher energy requirements and can increase the risk of oil contamination in some industries, making them less environmentally friendly than oil-free compressors. If your business has to meet specific environmental regulations, an oil-free compressor may be better suited to your applications.
Read More: Oil/Water Separators for Compressed Air Systems: Complete Guidelines
Oil-free air compressors were created to reduce oil contamination in the air stream and the problems with oil carryover. The main advantage of oil-free air compressors is that they offer cleaner, drier air, which is essential in specific industries. However, oil-free compressors have some drawbacks to consider before deciding between the two options.
While oil-free air compressors don't use oil to keep their components lubricated, they still pose a risk of oil contamination. If any oils exist in the air, such as lubricants used in production or vaporized metalworking fluids, these oils can be absorbed by the air intake and end up in the compressed air supply. The only cases where oil-free air compressors can reduce oil carryover to zero is if the air supply is pristine. Otherwise, you'll need filters to prevent oil carryover and contamination.
Some other drawbacks of oil-free air compressors include the following:
Despite these drawbacks, some industries should use oil-free air compressors over lubricated air compressors, such as those that need to reduce oil contamination as much as possible. However, using lubricated air compressors in sensitive industries is still possible when you utilize high-efficiency filtration.
The answer to whether oil-free air compressors are better than oiled air compressors depends on the needs of your applications. You'll want to consider different factors, including:
Regardless of which type of air compressor you choose, Fluid-Aire Dynamics is here to help. We can help you transition from one type of air compressor to the next, depending on which is best suited to your applications.
Our team can help you find an air compressor that suits your needs, whether you need to reduce oil contamination or want an air compressor that can serve your business for as long as possible. We can also help you find a high-efficiency filter that helps reduce oil contamination and carryover in your business.
You can browse our complete collection of air compressors. To find out more or for a free estimate on air compressors for your business, contact us today.
Want more information on chinese small air compressor manufacturers? Feel free to contact us.