Can anyone tell the advantages of multistage air compressor over single stage air compressor?

Question

explanation wd full working.

Answer 1

I guess you didn't like the answers you got before but that doesn't make them less accurate.

Here is my answer again. It comes from many years of designing, installing and operating compressors of all kinds. Remember, an engineer wants a simple system if possible. A single stage compressor is more desireable if it will do the job but as some point multistate compressors become necessary.

One of the primary problems that positive displacement air compressors face is high discharge temperatures. The high temperatures can cause or accelerate lubrication problems and valve failures.

If the compressor is a non lubed version the high temperatures can also contribute to piston ring problems.

By having multistages, you can intercool the air and reduce the discharge temperature on each stage. In addition to helping with valve, lubrication and piston problems, the required horsepower for a give capacity is reduced.

The other limit that comes into play for positive displacement piston type compressors is rod load. That is the limiting force that can be placed on a given cylinder on a compressor frame. If the compression ratio is too great, the force exerted by the compressor rod can exceed the capability of the compressor frame and some component will fail. It might be the actual rod or it could be the crank bearings or other components. Typically it is the rod so any failure will not wreck the whole compressor.

There are many positive displacement air compressors that are multistage. This is specially true in small size units.

Answer 2

. A compressor takes air and reduces its volume by some factor, called the compression ratio. It increase pressure by the inverse of the same ratio.
. For a piston type compressor, the compression ratio is machanically limited by the stroke, and it has a practical limitation due to the increase in temperature which goes along with compression. By using two stages, you can achieve a higher compression ratio with a relatively short stroke by compressing the air twice. The second piston will be smaller than the first because it is taking in the reduced volume of air put out by the first cylinder. Having two stages also allows for cooling of the compressed between the stages so that temperature rise is less of a problem.
. In a centrifugal compressor, you are using a centrifugal effect created by a spinning impeller to cause air to move from a low pressure region to a high pressure region, the opposite of the direction it would normally flow. You are again achieving a compression ratio, but in this case, the air has a clear path to flow from high pressure to low pressure, just like it wants to do. The only thing making it flow toward the higher pressure is the centrifugal effect. You can increase the centrifugal effect by spinning the impeller faster and/or making the impeller a larger diameter. Spinning it faster increases the centrifugal stress on the impeller, which could make it break apart. Making the diameter larger makes the compressor less compact. These limitations limit the compression ratio which can be practically achieved in a single stage. To go for a higher compression ratio, it is more practical to use a second stage which further compresses the output of the first stage. Again, because of the smaller volume flowing through the second stage, it will be smaller than the first stage.

Answer 3

Multistage compressors are typically able to achieve greater pressures. It can also achieve an equivalent pressure of a single stage compressor with less strain on the individual stages.The reason for this is that each stage needs only compress a portion of the total pressure. Each stage will also have to disipate less heat, making for easier cooling.

The downside of these is more moving parts.

Answer 4

2 stage normaly have more volume but same pressure