Episode 74: When Air Systems Outgrow the Plant

Jason Reed

Welcome to the show. Jason Reed here with Lisa Saunders. Lisa, picture a shop that adds two CNC machines, maybe a dicing saw, maybe just one more packaging line, and nobody touches the air system because on paper the compressor still looks fine. Then all of a sudden the guys on the floor are saying, “Why are these tools dragging?” That is how this stuff usually shows up -- not as a big dramatic failure, but as a bunch of little ugly symptoms.

Lisa Saunders

[curious] The phrase “tools dragging” is the whole story, isn’t it? Because nobody walks in saying, “I believe our system CFM profile has changed.” They say the grinder feels weak, the actuator is slow, the machine isn’t hitting torque, the product quality got weird. It sneaks in through operations, not through theory.

Jason Reed

Exactly. And if you’re short on air, the problems stack fast. Lower speed, lower torque, longer cycle times, more scrap, higher energy cost because everything takes longer to do the same job. And the one people skip over is safety. Any time you run a tool outside what it was designed for, you’re rolling dice.

Lisa Saunders

[questioning tone] Let me grab that “longer cycle times” part, because that’s the sneaky cost. If a tool takes, say, 15 seconds instead of 10, nobody panics over five seconds. But multiply that across a shift, across a line, across a month... now your “we didn’t need to upgrade air” decision is eating production.

Jason Reed

[matter-of-fact] Right. And people assume the only way to outrun the air system is adding more demand. That’s not true. You can break performance by just changing the layout. Move machines farther away, add longer pipe runs, relocate storage, add a second building -- now you’ve introduced pressure drop where you didn’t have it before.

Lisa Saunders

Wait -- that “second building” example is a good one. Because from a manager’s point of view, they think, “We already own compressed air. We’ll just extend it.” But distance is not free. A longer run can mean the pressure at the tool is not the pressure you thought you had back at the compressor room.

Jason Reed

That’s it. The compressor can be doing its job and the end use still starves. I’ve seen plants chase the wrong problem for weeks because the machine operator says the process is unstable, maintenance checks the tool, production blames the machine OEM, and meanwhile the real issue is the air got worse when the facility changed.

Lisa Saunders

[skeptical] And this is where I think people get tripped up by the phrase “we’re only adding one shift.” Only one shift? That can be a massive change. If your demand pattern used to fall off at night and now it doesn’t, your whole operating rhythm changed. Your compressor doesn’t get to live the same life anymore.

Jason Reed

Yep. New shift, new machine, expansion, even rearranging the floor -- all of that can change demand, pressure stability, and air quality needs. Especially if the new equipment wants cleaner, drier air at a tighter pressure band. Modern printers, CNC equipment, automation components -- some of that stuff is not forgiving.

Lisa Saunders

[lightly] Compressed air is funny that way. It’s treated like background utility... right up until the background utility starts wrecking the foreground.

Lisa Saunders

So let’s flip it, because this part surprises people more. Downsizing sounds like good news. You shut down a line, move work out, lose a third shift -- now you’ve got extra capacity. More air than you need. That sounds comfortable. But in a rotary screw setup, “comfortable” can turn into “wrong” pretty fast.

Jason Reed

[firm] Too much capacity is a real problem. When the compressor is oversized for the way the plant runs NOW, it can start and stop too often. That’s short cycling. And short cycling is hard on motors, valves, bearings -- the whole machine. It wastes energy, creates overheating problems, and can carry over moisture and oil.

Lisa Saunders

“More air than you need” causing moisture and oil carryover -- that’s the part that sounds backwards to people. They hear extra capacity and think cushion. But what you’re saying is the machine never settles into a healthy operating pattern.

Jason Reed

Exactly. Rotary screws like to run properly, not bounce in and out all day. If a big motor is starting and stopping over and over, you’re chewing it up. I mean, manufacturers will flat-out warn against frequent starts. This isn’t some theoretical best practice thing. Burn up a motor and now your “free extra capacity” gets real expensive.

Lisa Saunders

[reflective] So the better question isn’t, “Do we have enough air?” It’s, “Does this system match how we actually operate today?” Because “today” might mean fewer lines, variable demand, one busy season, one slow season, or different shifts than you had two years ago.

Jason Reed

That’s the right question. And sometimes the answer is you need a smaller machine. Sometimes it’s staging compressors differently. Sometimes it’s adding storage. Sometimes it’s looking at variable-speed drive technology because demand isn’t flat anymore. But you can’t answer any of that by eyeballing the nameplate and guessing.

Lisa Saunders

[responds quickly] Okay, let me say it back and you tell me where I’m wrong. Undersized hurts because the plant can’t do the work. Oversized hurts because the compressor can’t do its own work efficiently. Different failure, same result: wasted money and reliability problems.

Jason Reed

[chuckles] That’s actually clean. Yeah. One starves production, the other abuses the air system. And both usually happen after change. Not during steady state -- after change.

Lisa Saunders

Which brings us to the boring answer that is, annoyingly, the smart answer: baseline the system before you need the answer. Track actual CFM demand, pressure, energy use, load hours, run hours, and pressure drops. Not once. Ongoing.

Jason Reed

[matter-of-fact] Baseline is everything. If you know what normal looks like, then when the plant adds equipment or cuts a shift or starts missing pressure at the far end of the building, you’ve got something to compare against. Without that, every change becomes a guessing contest.

Lisa Saunders

And baseline also tells you when the issue is not capacity alone. Maybe regulations changed and now air quality matters more. Food, beverage, pharma, healthcare, electronics -- those environments can force you to rethink filtration, drying, maybe even whether your air approach is appropriate for the product.

Jason Reed

Right. And then there’s seasonality. Candy plants ramp before the holidays. RV manufacturers gear up for spring. Textile output can shift with seasonal demand. So the system that looked perfect in February might be wrong in October. That’s why I like data that covers real operating periods -- not just one clean week.

Lisa Saunders

[curious] And when that baseline shows the plant is changing, the fixes are not always “buy more compressor.” It might be more storage. Better drying. Better particulate and coalescing filtration. A backup machine for redundancy. A VFD because your demand swings all over the place. Or just fixing the layout so the pressure drop isn’t killing you at the far end.

Jason Reed

Yep. Compressed air problems love to dress up as simple compressor problems. Sometimes they are. A lot of times they’re system problems. Storage, controls, piping, filtration, drying, backup strategy -- it all matters once the operation changes.

Lisa Saunders

[softly] I think that’s the real tension here. Change at a plant usually feels urgent. New line, new building, new schedule, new compliance requirement. Everybody moves fast. And compressed air gets treated like something you can sort out later.

Jason Reed

[serious] And later is when the downtime shows up. The best time to prepare for a production change is before it lands on the floor. Because once people are standing around a machine that won’t run right, you’re not adapting anymore -- you’re recovering.

Lisa Saunders

[calm] That’s the line. Prepare before the change, or pay during it.

Jason Reed

I’ll take that. See you next time.