What is a Hydraulic Ram and How Does It Work?

A hydraulic ram is a cylinder with a movable rod that can move a mass, or an obstruction as so required.

In principle, a hydraulic ram works by an external fluid being pumped into either side of a cylinder simultaneously, this creates a high pressure and low-pressure side within the cylinder depending on the load that it is trying to move.

Here we explore some of your commonly asked questions surrounding hydraulic rams, what they’re used for, how hydraulic devices work, and how hydraulic rams work.

How does a hydraulic device work?

Hydraulic devices use fluid that is moved by an external pump driven by a power unit. Hydraulic devices are designed around the principle that liquids are always considered to be incompressible. This means that when a force is applied at one point, the liquid will transfer an equal force at another point.

Most common hydraulic devices work by using a hydraulic pump, a reservoir for fluid storge to the pump. Mechanical energy is converted to hydraulic energy, moving the liquid through a system. Valves are used to regulate the flow of the liquid and control the pressure of the device. A hydraulic cylinder then converts the hydraulic energy back into mechanical energy.

There are a variety of hydraulic devices, including hydraulic rams, but most will use these components in their operation.

How do hydraulic rams work?

Hydraulic rams consist of several components:

• Cylinder
• Piston
• Neck Gland
• Rod
• Cylinder Ports
• End Caps

The area between the piston and the gland (rod side) is called the Annular side, & the area between the piston & the end cap is called the Full-Bore side.

Pumping fluid into the cylinder port on the Annular side of the cylinder will result in the rod being retracted, giving you a closed centre. Reverse the flow into the opposite port on the Full-Bore side and the piston will then extend the rod out of the cylinder (open centres), at the same time pushing the oil from the Annular side (low pressure) back to tank.

What is a hydraulic ram used for?

Today, hydraulic rams are used all over and have a variety of uses, from heavy plant and mining machinery such as excavators and diggers, agricultural equipment, to food & beverage and packaging machinery, deep sea, marine and automotive applications, to hand tools, fairground amusements and even zoo doors...the list goes on and on.

FPE Seals is a manufacturer and distributor of hydraulic cylinder parts and seal kits for devices including hydraulic rams. Shop online or contact us and find out how our cylinder parts can help improve your hydraulic systems.

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