One of our media partners recently quizzed their subscribers to assess users’ knowledge about compressed air systems. The respondents were in the automotive service industry, but the questions were not industry or application specific and the answers are a fair reflection of compressed air knowledge of most businesses with compressors 25 hp and below. We thought it would be useful to present the results and discuss areas where understanding of compressed air systems needs a boost.
A strong majority (84%) of respondents knew that reciprocating/piston type compressors operate at higher internal temperatures than rotary type compressors, but nearly 1/3 mistakenly thought that shop recips could safely run at 100% duty cycle. Some recips are built to run at higher duty cycles than others, but all air-cooled units need at least some downtime to cool off. The consequences of overrunning them include loss of lubrication, seizure, motor failure and higher oil carry-over into paint and equipment.
Regarding piping, nearly 2/3 know that copper or aluminum are better choices– especially if air quality is important– but a full 20% picked PVC as top choice. While PVC doesn’t accumulate or add contaminants, it presents one major problem:
Wait for it ….
Yes, PVC is less safe than any metal pipe and is subject to rupturing and fragmenting.
When presented with five possible solutions for solving a low pressure problem, everyone recognized that buying another (or larger) air compressor to get more flow is not the first step to address the problem. Checking for leaks, checking pipe size, adding storage and doing a pump-up test to check compressor function were all known to be better first steps. We were pleased to see that over 80% recommended doing all of these things before buying another compressor to get more flow (cfm).
Likewise, we were pleased to see that everyone knew that a compressed air dryer is a simple solution to address the common summertime problem of increased water in compressed air lines and tools. It’s apparent though that not everyone understands the difference between dryers and other devices that remove some moisture. Filter style moisture separators (with drain valves) are effective at removing liquid water. Storage tanks do the same and can allow some moisture vapor to cool and condense to liquid, but the key to effective drying is reducing the compressed air pressure dew point below the ambient temperature. Tanks and filters cannot do it. A dryer can.
The last quiz question was about compressor sizing. Since this topic is a bit more complex it deserves its own post. Stay tuned…