What Is a Hydraulic Puller?
A hydraulic puller is a tool used to remove gears and bearings using hydraulic force.
Gear pullers and bearing pullers pull out gears or bearings with the force of a screw, while hydraulic pullers use stronger hydraulic pressure.
Hydraulic pullers use stronger hydraulic pressure, which is especially necessary when removing bearings that have been hard-fitted together. They can also be used as a last resort to remove rusted or seized gears and pulleys that cannot be removed with a threaded puller.
How to Use a Hydraulic Puller
Hydraulic pullers, like gear pullers and bearing pullers, are used by hooking the jaws onto the object and pulling it out. However, a hydraulic cylinder is used for the part that touches the shaft.
The rod of the hydraulic cylinder is placed against the shaft while the hydraulic puller hooks its jaws onto the object. Then, oil is fed to the hydraulic cylinder with a manual hydraulic pump. The handle of the hydraulic pump applies many times more force to the hydraulic oil than is applied by hand due to the principle of leverage, resulting in strong pressure that propels the hydraulic cylinder forward. Each time the hydraulic cylinder moves forward, the object is pulled out.
How to Choose a Hydraulic Puller
There are several types of hydraulic pullers. The main difference lies in the mounting method of the hydraulic cylinder. Here are the advantages and disadvantages of each:
- Direct Mounting Type
The hydraulic cylinder is directly attached to the extrusion. The hand pump for pressurization is often directly connected to the cylinder. Since the hand pump is directly attached to the main body, the hand pump used cannot be too large, and the pushing force is somewhat smaller. - Feed Screw Bottom Type
A hydraulic cylinder is attached to the bottom of the feed screw for pushing. When the tip of the hydraulic cylinder is applied to the shaft, it can be set quickly by bringing it close to the screw. Many types of hand pumps are connected with a hose. Since the hand pump can be installed separately, its size can be increased. Therefore, the hydraulic pressure delivered is also larger, and gears and bearings can be pulled out with very strong force.