By Ron Marshall for the Compressed Air Challenge A metal fabrication facility ran two separate systems to feed tools and equipment in two shops on their premises. One compressor ran load/unload, the other was a VSD controlled compressor. The plant maintenance engineer attended a Compressed Air Challenge seminar, and as a result, came to realize how […]
Air Preparation
How do I control multiple compressors, Part 2?
To continue this simple question with a complicated answer, in this blog post we will deal with rotary screw compressors, the most common type of compressor found in industrial sites. If you have small reciprocating compressors, go back to Part 1 of this discussion. Controlling multiple rotary screw compressors gets more complicated as the number of system […]
How do I control multiple compressors, Part 1?
This is a simple question with a complicated answer. It depends on the type of compressors you have and what your goals are in terms of energy efficiency and pressure control. This first blog post deals with small reciprocating compressors; as for the control of screw compressors, we will save for part 2. If your system […]
Can air compressor heat be recovered?
The recovery of compressor heat can substantially reduce the total cost of energy in most commercial or industrial facilities. Thanks to the laws of physics, the most plentiful useful output of an air compressor is heat. Less than 10% of the air compressor energy input is actually turned into useful work at compressed air powered machines […]
Compressed Air Fail: Air dryer purge
By Ron Marshall for the Compressed Air Challenge A grain products company was increasing their production capacity and needed a new compressor and dryer. The budget was tight, so the company searched and found some used equipment to meet the need. Rather than running the lubricated compressor in modulating mode like the previous compressor, the […]
How costly is my desiccant dryer?
Desiccant units will consume about 2 to 3 kW of energy for every 100 cfm of dryer rating, compared to about 0.8 kW per 100 cfm for refrigerated dryers—almost 4 times as much! But if you have a desiccant style air dryer in lightly loaded conditions, it may be costing you more than you think. […]
Why is my compressor room so hot?
The physics of compressed air dictates that heat must be generated if air is compressed. The amount of heat depends on the size of the compressor. For example, a fully loaded 25 hp compressor will produce more than 63,000 Btu/hr of heat—if you do the math, this is the equivalent to about 18 kW of power. […]
What size air compressor do I need?
Determining what size of compressor to buy is a very difficult problem. This is especially true if the compressor will be for a new system that hasn’t been built yet. If you answer this question wrong, you might end up with pressure problems if the compressor does not have enough output to feed peak air […]
How many horsepower should a 100 hp compressor consume?
CAGI Sheets tell the story! When you buy a 100 hp compressor, how many horsepower do you think it should consume? Yes, this is a trick question. Compressor ratings are often confusing when it comes to checking the specifications of screw compressors. The 100 hp associated with the Compressed Air and Gas Institute (CAGI) compressor data […]
What’s more efficient, reciprocating compressor or screw air compressors?
Often, when it comes to choosing an air compressor for a service shop, there is a choice between types and sizes of compressors. Do you choose a standard reciprocating compressor or do you go with a more modern lubricated screw? But depending on the way you use your compressed air, and how the compressor is […]