Before buying a compressor, it’s always smart to do some research. There are so many varieties of compressors that it can be overwhelming at first. Below are some common choices you may face when determining which compressor is best for your facility.
Fixed speed or VSD?
Whether or not you need a fixed speed or variable speed drive (VSD) compressor largely depends on the required cfm and air demand fluctuation of your application. If you have a relatively low cfm requirement with a peak hour demand that is significantly higher than usual, a VSD compressor may be right for you. VSD compressors are modulated to produce only the necessary amount of air at a given time. On the other hand, if you need compressed air for a constant application with only slight changes in demand, a fixed speed compressor that operates at set speeds may be a better option. If your application requires a large source of compressed air with some fluctuating demand, the solution may be a fixed speed compressor for base loading and a VSD compressor for trim duty.
Oil-injected or oil-free?
Choosing between an oil-injected and oil-free compressor is simple. All you have to do is consider your end use. If there are safety requirements regarding air purity, an oil-free compressor is usually the way to go. These compressors do not use lubricants during the compression process, so there is no risk of contamination. Oil-free compressors are frequently used in pharmaceutical, food and beverage, and electronic production industries. Even though oil-injected compressors provide levels of filtration to remove hydrocarbon aerosols from the air stream, they still should not be used in sensitive applications. Check out the ISO classifications for air compressors and compare your industry’s purity standards.
Dynamic or displacement?
Dynamic and displacement compressors are the two general categories of air compressors. A dynamic compressor works by drawing air between the blades on a rapidly rotating compression impeller that accelerates to high velocity. Then, it discharges that air into a diffuser to turn the kinetic energy into static pressure. The second category is displacement compressors. These operate by enclosing air in a chamber and reducing the volume through displacement of one or more moving parts. Many dynamic compressors are also considered turbo compressors and are ideally suited for high-volume flows. While each type of compression can be used in almost any application, dynamic compression is usually best for base-loading, while displacement compressors work well with variable loads.
Open or closed canopy?
Deciding on an open or closed canopy is mostly a matter of preference. Each offers advantages and disadvantages. While open canopy compressors are easy to access for maintenance, closed canopy compressors provide some noise reduction and block the inner workings from ambient dust or debris. It’s also important to consider any safety concerns if an open compressor will be housed on the facility floor or near workers.
Before purchasing a new compressor, make sure you understand the needs of your facility as well as your personal preferences. Do you have variable or consistent demand? Is any air purity level acceptable, or are there strict quality standards? Would you prefer an open canopy or a closed, integrated system? Work with an expert to help identify the needs of your facility and match those with the best compressor for your application. Contact an Atlas Copco expert today to get started.
