How does hydraulic cylinder work with one hose? That is a question that will be thoroughly answered in this article.
A single-acting cylinder is only able to move in one direction actively. It is because it only has a hydraulic fluid port on one side. It returns with the help of external forces such as spring.
The first day I came across it, it was very strange to me too, but after digging deep through research, I later understood how it works, which I will explain in detail below.
Will like to know the two types of hydraulic cylinder, click here to read.
How Single-Acting Hydraulic Cylinder Work
A single-acting cylinder is only able to move in one direction actively. It is because it only has a hydraulic fluid port on one side.
The simple cylinder can move back into position by passive movement in several ways, for example, through its weight, an external force in the form of a spring return or through direct external influences such as the weight of a vehicle, which ensures that a lifting platform is lowered again.
How are single acting hydraulic cylinder retracted?
single-acting hydraulic cylinders consist of a cylinder tube in which a piston with a piston rod is guided up and down with the help of hydraulic power, and the fluid pushes the piston.
The cylinder’s piston and sealing system create a chamber filled with hydraulic oil during operation.
The oil is pressed into the chamber at high pressure by hydraulic pumps or hydraulic units.
Due to the increasing pressure in the chamber, the piston and the piston rod extend.
Single-acting hydraulic cylinders use the weight of the load being lifted or the system’s weight to retract. Another way it retracted is by using a spring. The spring helps the single-acting hydraulic cylinder to reset.
There is only one supply hose, and the force of the weight or the spring serves as means of retraction.
An external force is required to retract a single-acting hydraulic cylinder.
How Do You Bleed Single Acting Hydraulic Cylinder
Follow the step listed below:
Step 1. Get the air to the top: You can activate the cylinder until it extends to the maximum. Then you allow it for some minutes.
By doing so, you are gathering all the air to the top without a way out.
Step 2. Vent out the air: After some minutes, you can gradually close the cylinder, but not completely, and then you open the bleed valve.
Allow the air to flow until you notice no air trapped inside the cylinder again. When the air is cleared, you will notice that only hydraulic oil is coming out.
At thing point, you can close the bleeding valve. Note: you need to put a container under it so the oil will not spill on the ground.
Step 3: The next step is to test the cylinder to see how it works to ensure there is no longer air in the cylinder.
If you notice there is still air, then repeat step1 and step 2 to be sure of the bleeding process.
How Many Port Does A Single Acting Hydraulic Cylinder Have
As the name implies, a single-acting hydraulic cylinder has only one port. Unlike a double-acting hydraulic cylinder with two, a single-acting has just one port.
From there, the hydraulic supply to the cylinder pushes out the piston. The cylinder retracted with the help of external force such as load or spring.
What Are The Single Hydraulic Cylinder Examples
in this article, I will mention two examples of single-acting hydraulic cylinders.
1 . A typical example of a single-acting hydraulic cylinder is a lifting platform like that found in car workshops.
The car’s weight ensures the lifting platform can be lowered again after work.
Alternatively, with single-acting hydraulic cylinders, springs can also move the piston back.
2. Hydraulic jack: A car jack is a typical single-acting hydraulic cylinder.
It has only one port where you fill in jack oil. But to retract it, you need to release the jack lock, and the load’s weight will bring down the piston.
Final Thought
From what I have written, you have seen how hydraulic cylinder work with a single hose.
And don’t forget how to bleed a hydraulic cylinder that is a single-acting or single port with the help of a bleeding valve. I also stated two good examples of a single-acting hydraulic cylinder.
Click here to read why hydraulic cylinder to bypass.