Hydraulic Accumulators

We know accumulators

With over 30 years combined working experience with the market leader of hydraulic accumulators Exotech has the knowledge & product to meet your needs today! 
Whether you have an old Christie Hydraulics AC37, Fawcett SA18.8, AC0400A-00-34A, G11 or even a Greer 60A-21 Exotech can identify and offer a current model to meet todays stringent OH&S requirements.

With such a prestigious history many companies manufactured accumulators under license with the  Greer-Mercier design including:

Fawcett Engineering , Christie Hydraulics , Fawcett Christie Hydraulics (FCH), OLAER, OILTECH, Olaer Fawcett Chrisite (OFC) , OILAIR Hydraulics

What is a hydraulic accumulator?

Imagine a hydraulic accumulator as a rechargeable battery for your hydraulic system, but instead of storing electricity, it stores hydraulic fluid under pressure. 🔋💧

Think of it like this: sometimes your hydraulic system needs a sudden burst of energy, or needs to handle a shock, or just keep things running smoothly even if the pump isn’t constantly working at full tilt. That’s where an accumulator comes in handy.

How Does It Work?

At its core, an accumulator is a pressure vessel with two compartments, usually separated by a flexible barrier like a bladder, a diaphragm, or a piston.

1. Gas Side: One compartment is pre-charged with an inert gas, typically nitrogen. Think of this as a compressible spring. 🌬️
2. Fluid Side: The other compartment is connected to your hydraulic system and fills with hydraulic fluid.
3. Storing Energy: When the hydraulic pump pushes fluid into the accumulator, the fluid pressure forces the barrier (bladder, diaphragm, or piston) to move, compressing the nitrogen gas. This compressed gas is what stores the energy. It’s like squeezing a spring.
4. Releasing Energy: When your system needs that stored energy (e.g., an actuator needs to move quickly), the pressure in the hydraulic system might drop slightly. The compressed nitrogen then expands, pushing the stored hydraulic fluid back out into the system, providing that extra power or maintaining pressure. 💪

Main Types of Accumulators

There are a few common types, named after the kind of barrier they use:

• Bladder Accumulators: These use a flexible rubber bladder to separate the gas and fluid. They’re very common, respond quickly, and are good at handling high-frequency pulsations. Think of a strong balloon inside a steel shell.
• Diaphragm Accumulators: These use a flexible diaphragm (like a tough rubber sheet) to separate the gas and fluid. They are often more compact and can be good for lower-volume applications and handling pressure shocks.
• Piston Accumulators: These use a sliding piston, much like in a hydraulic cylinder, to separate the gas and fluid. They are robust and can handle very high pressures, large volumes, and high flow rates.

Why Use an Accumulator? (Common Applications)

Engineers use hydraulic accumulators for several key reasons:

• Energy Storage: To supplement the pump. The accumulator can store energy when demand is low and release it during peak demand. This means you might be able to use a smaller, more efficient pump. ⚡
• Shock Absorption (Dampening): Hydraulic systems can experience sudden pressure spikes (like “water hammer” when a valve closes quickly). An accumulator can absorb these shocks, protecting components and reducing noise and vibration. 🌊➡️😌
• Pressure Maintenance: If there are small leaks in the system or if the temperature changes causing fluid to expand or contract, an accumulator can help maintain a more constant pressure.
• Emergency Power: If the main power to the hydraulic pump fails, a charged accumulator can provide temporary power to, for example, safely retract a cylinder or close a critical valve. 🚨
• Pulsation Dampening: Pumps, especially piston pumps, can create pressure pulses. An accumulator can smooth these out, leading to a quieter and more stable system.

So, in a nutshell, a hydraulic accumulator is a device that makes hydraulic systems more efficient, reliable, smoother, and safer by storing and releasing hydraulic energy when needed.