The four-way valve is a simple device for controlling the flow of fluid in a system. These valves are spool-type, with the advantage of having equal surface areas for the pump and the tank. They also have a vertical symmetry, making them an ideal choice for applications requiring the control of a fluid flow. 

A four-way valve has four ports around its chamber. The valve’s cock plug has two passages that connect adjacent ports. It can be cylindrical, tapered, or ball-shaped. 

Each port has two flow positions, and the plug is normally located centrally. In addition, when the valve is in a closed position, the inlet and exhaust ports both remain open. 

If you want to know more about a 4-way valve and how it works, continue reading this article. 

What Is a Four-Way Valve?

When you see a 4-way valve, it looks like a simple directional control valve. However, it is often used in double-acting cylinder applications. This type of valve has 4 ports and two flow positions. These valves always supply pressure to one side of the cylinder while allowing the opposite side of the cylinder to be emptied into the atmosphere. As a result, they are very common in double-acting cylinders. The name comes from the four positions the valve can accommodate.

These valves are useful for sequential positioning because they are able to change direction without losing the signal. A four-way valve is most suitable for applications where pressure changes over time, and it is also useful for pool chemical treatment and water softener regeneration. 

These valves were first used in early double-acting steam engines. The four-way valve consists of two “L”-shaped passages that do not interconnect, one on each side of the plug. The two “L”-shaped passages in the plug are not connected, making it difficult to identify a four-way valve in an unfamiliar setting.

The Working Mechanism of a Four-Way Valve

In an early double-acting steam engine, a four-way valve was used to control the flow of steam to the cylinder. The working mechanism of a four-way valve involves two “L-shaped” passages that do not interconnect. In addition, a 4-way valve is also known as an “x port.”

In actuator applications, a four-way valve may be left in the block position. In this case, the valve transfers hydraulic pressure from the manifold to the cylinder’s closed port, and the same pressure returns to the reservoir tank. A four-way valve may be left in the block position when the rig is being moved or is repairing itself. 

The four-way valve has four ports. The valve has a universal function, which allows it to work as a diverter as well as a regulator. This type of valve has two flow positions. When the valve is in the central position, it is closed. There are a total of four or five pipes connected to this valve. You can either fully close the valve, fully open the valve or partially open the valve.

When you move it to the opposite position of the central position, the valve is fully open. However, when you move the handle halfway, it is partially open. With these valves, you can easily reverse the motion of a cylinder or a motor.