Here’s the revised version with that part removed and everything flowing cleanly:
Fluid Power Fundamentals – Session 2 Recap
by: Donna Pollander, ACA
Session 2 picked up right where we left off—diving deeper into hydraulic systems and proving that, yes, those symbols do start to make sense… eventually.
If Session 1 was the “what is this stuff?” conversation, Session 2 was more of a “okay, let’s actually read and build this thing” experience.
Session 2 Highlights
BJ Wagner continued leading the course, guiding participants through hydraulic circuit fundamentals, symbology, and components—with plenty of real-world context (and just enough brain exercise to remind everyone this isn’t a passive activity).
We started with parallel vs. series circuits, revisiting a familiar concept but with more depth. The big takeaway? Fluid behaves a lot like people—it takes the easiest path available. In parallel circuits, that means flow follows the path of least resistance. In series circuits, pressure drops stack up, which sounds harmless until you realize that lost energy turns into heat… and heat is basically your system complaining.
Speaking of inefficiencies, the group explored how restrictions—like the wrong fittings—create pressure drops and waste energy. The solution? Better design… and sometimes a heat exchanger to keep things from getting too spicy.
From there, BJ walked through system efficiency calculations, showing how quickly performance can drop when you stack component losses. Even a “pretty efficient” system still leaves some energy on the table—so sizing your prime mover correctly is key. (Translation: don’t underpower your system and hope for the best.)
Decoding the “Secret Language” of Schematics
Next up: symbology—aka the part where hydraulic diagrams stop looking like abstract art.
Participants learned how to interpret:
Line types (solid, dashed, dash-dot… yes, they all matter)
Flow direction and connections
Core component symbols for pumps, motors, valves, and sensors
The big realization here? Every tiny detail in a symbol means something. Flip it, add a line, change an arrow—and suddenly you’ve got a completely different component. No pressure.
BJ also showed how simple symbols combine into more complex components like pilot-operated valves and flow controls—kind of like LEGO, but with higher stakes.
Pumps, Motors, and Cylinders
The group reviewed hydraulic pumps and motors, including fixed vs. variable displacement and how to spot bidirectional operation in a schematic.
Hydraulic cylinders got their moment in the spotlight—single acting, double acting, telescopic, cushioned—you name it. Participants learned how to identify them and understand where they’re used (from jacks to steering systems).
Valves and All the Moving Parts
Then came directional control valves, where things got interesting:
Different actuation methods (buttons, levers, pedals, and more)
Various center conditions (open, closed, tandem, regenerative—basically, choose your own adventure)
Proportional valves for more precise control
If you’ve ever wondered why a system behaves a certain way in neutral, this is where those answers live.
The session wrapped up with pressure control valves—relief, reducing, sequence, unloading, and counterbalance valves—each playing a critical role in keeping systems safe and functional.
Practice Makes (Closer to) Perfect
To tie it all together, participants worked through identifying components in sample circuits. It’s one thing to learn symbols—it’s another to look at a full diagram and confidently say, “Yep, I know what’s going on here.”
Progress.
Final Thoughts
Session 2 turned up the pressure (in a good way), moving from basic concepts into real interpretation and application. The takeaway? Hydraulic systems aren’t just about moving fluid—they’re about understanding how every component, symbol, and decision fits together.
Also, schematics are no longer mysterious… just slightly less intimidating.
Stay tuned for Session 3—things are continuing to flow nicely.
