Air compressors have become a necessity for the day-to-day operations of most companies. While businesses realize that they need an air compressor, what they aren’t able to decide is if they should opt for the rotary screw compressors or reciprocating air compressors, both being the most popular of air compressor types.
Facts To Consider
Before delving into the details of what makes either of them a better choice, here are a few facts to consider:
Rotary air compressors are highly preferred in applications of above 15 hp and plant air requirements of up to 150 psig.
Reciprocating air compressors are preferred for applications requiring lower horsepower but higher stability.
Oil-less or oil-free air compressors are not only a pricey buy but also entail a high maintenance cost.
Rotary air compressors comprise of 40% of the total market share, whereas reciprocating compressors comprise of 21% only.
Now, let’s look at the features of each of the compressors in terms of the most important qualifiers.
Rotary screw air compressors are the preferred choice for applications that require high power output (above 15 hp), the drivers of its low noise and high duty cycle, and improved performance and reliability. Even though the old school, double-acting reciprocating air compressors offer higher efficiency at power levels the newer builds of rotary air compressors with design innovations, machining improvements, and better rotor profiles have helped bridge the efficiency gap by significant levels. Besides, double-acting reciprocating air compressors entail high initial costs which can be justified only if the plant’s power requirements are very high. With rotary screw air compressors however, the power output levels can be regulated to match the plant’s power needs.
For lower power output (below 15 hp) with higher stability, reciprocating air compressors work best. Their simple design, wide range of operation and proven reliability makes them ideal for large and small air cooled units for harsh environments.
Rotary screw air compressors have been designed to make maintaining them easier. Most of the maintenance in them is restricted to oil/air separator, oil filter, air filter element and oil changes, with rotary screw air end replacement is required when the bearings fail.
When choosing between lubricated and non-lubricated reciprocating air compressors, there are a few things to consider. Since lubrication of the compression cylinder helps minimize the wearing of piston and cylinder rings, lubricated reciprocating air compressors last longer than non-lubricated ones. Though advancements in the new compression ring materials have helped increase the life span of non-lubricated compressors as well.
The initial cost of both kinds of reciprocating air compressors is also different, with non-lubricated reciprocating air compressors being 10-15% costlier than lubricated ones. Moreover, the maintenance cost of the two is also worth considering – the cost of maintaining non-lubricated reciprocating air compressors being four times more than lubricated ones.
Besides the above factors, buyers may also want to consider the installation parameters and costs, when purchasing an industrial air compressor.
Conclusively, choosing the best rotary screw air compressor or reciprocating air compressor is largely dependent on what your air compression needs are, for which considering the above parameters is important.