In the world of hydraulics, the terms “ram” and “cylinder” are often thrown around interchangeably. You’ll hear operators say their “ram’s leaking” or that a “cylinder blew a seal.” But while many in the industry use both terms to mean the same thing, the truth is a bit more nuanced, and understanding the difference can help you make better decisions about maintenance, repairs, and equipment selection.
At Finer Hydraulics, we work with hydraulic cylinders of every type and application, and while we’ll understand what you mean if you say “ram,” it’s worth unpacking what these terms really mean and why precision matters.
What Is a Hydraulic Cylinder?
A hydraulic cylinder is a mechanical actuator that converts hydraulic energy into linear force and motion. It consists of several key components:
- Barrel: The outer casing that holds the hydraulic fluid
- Piston: Located inside the barrel, it separates the internal chamber and moves under fluid pressure
- Rod: Attached to the piston and extends outside the barrel to do work
- Gland and seals: Prevent leakage and control movement
Hydraulic cylinders come in various designs, including single-acting, double-acting, telescopic, and differential, and they are found across industries, from earthmoving and agriculture to manufacturing and logistics.
What Is a Ram?
Technically, a ram refers to a very specific type of hydraulic cylinder: one where there is no piston, just a solid plunger or rod. The entire pressure is applied to the end surface of the rod itself. Rams are typically used in applications where high force is needed over a relatively short distance – think jacks, presses, or lifting equipment.
In everyday usage, however, “ram” is often used as a catch-all slang term for any hydraulic cylinder, especially in Australian and rural contexts. While this might work fine in casual conversation, it can cause confusion when ordering parts, specifying replacements, or diagnosing issues.
Why the Difference Matters
Knowing the difference between a true ram and a hydraulic cylinder matters for a few key reasons:
1. Component Compatibility
Seals, rods, barrels, and glands are not one-size-fits-all. Assuming a ram and a cylinder are the same could lead to using the wrong parts or tolerances. For example, a piston seal won’t exist in a ram, and trying to fit one could lead to wasted time or failure in the field.
2. Repair and Rebuild Considerations
A true ram is generally simpler than a standard hydraulic cylinder, but it’s not necessarily easier to repair. Reseals are different, tolerances are different, and damage is often harder to spot because there’s no piston to check. If you call something a “ram” when it’s really a double-acting cylinder, you might underestimate the time and parts needed for a proper repair.
3. Application Suitability
Choosing the right type of actuator for a job depends on the force required, stroke length, and control. Rams are ideal for powerful, single-direction force over short distances. Cylinders are better for more complex or precise motion in both directions. Mixing these up can result in poor performance or equipment strain.
4. Miscommunication with Suppliers or Workshops
If you’re ordering a replacement or sending a unit in for service, using imprecise terms can lead to delays. At Finer, we always clarify what type of unit you’re referring to, but not every supplier will take that time. Clear communication prevents errors and saves money.
Common in the Field: Why the Confusion?
In Australia, especially in agriculture and earthmoving, “ram” is the more commonly used term, regardless of accuracy. It’s often just shorthand for “the hydraulic thing that makes my attachment move.” While we all understand the intent, precision helps when the stakes are high, especially when downtime is costing you money.
We’ve had plenty of cases where a customer brought in what they called a ram, only for us to discover it was a custom double-acting cylinder with a failed piston seal and mismatched aftermarket parts. Had the job been quoted or prepped based on that assumption, both time and cost would’ve blown out.
Get the Right Part the First Time
At the end of the day, if you say “ram,” we know what you’re talking about. But behind the scenes, it pays to be specific. Rams and cylinders might look similar from the outside, but what’s going on inside, and how they’re built, used, and serviced, can be very different.
If you’re not sure what you’ve got on your machine, or you’re chasing a repair but don’t want to order the wrong parts, give Finer Hydraulics a call. We’ll take the time to identify the right component and give you the service it actually needs, not just what someone guessed it was.
