Hydraulic packing:
Packings are in the category of moving seals that are used to seal pump shafts and piston seals.
Their material is usually natural rubber or polyurethane.
The sealing process is one of the most important parts. It is considered in pistons.

Types of hydraulic packing
After placing the packing in the special sealing cavity, they are axially compressed by the "Gland" screws or the same sealing groove. Due to the plasticity of the packing, during the relative movement of the shaft and the packing, a radial force is created and causes the packing to contact the shaft. At the same time, the lubricant also creates a thin layer of oil on the contact surface. An oil groove is formed in the recesses where contact is not made. Therefore, the contact and non-contact parts create a spiral shape that plays an important role in preventing fluid leakage, and the principle of peking is also based on these thin and spiral-shaped layers.
In a good seal, the "Labyrinth" effect is well maintained, for this purpose compression and lubrication should be done properly. If there is too much compression and the lubrication process is not done correctly, the oil layer is not created well and there is friction without oil between the shaft and the "filler" (Filler), which causes corrosion and causes problems in the shaft. We said that packings are in the category of moving seals, which are used to seal pump shafts and seal pistons. Their material is usually natural rubber or polyurethane. The sealing process is one of the most important parts of pistons.
Piston packing:
This type of packing is usually used in hydraulic and pneumatic jacks, they are placed at the beginning of the cylinder to protect the piston from liquid or gas leakage, which ensures maximum sealing.
Throat packing:
This type of packing guarantees the sealing process to prevent the leakage of liquid materials in pneumatic jacks. The throat packing is placed at the beginning of the guide and applies the maximum amount of sealing in the opposite direction of the jack cylinder. They also prevent material from leaking out to improve cylinder performance.

Dust collector packing:
Dust collectors are usually produced from plastic material or synthetic rubber, which are often used in pistons to prevent dust from entering the cylinder and perform relative sealing to some extent. The body of some dust collectors is metal, which is installed only on top of the cylinder and has a high resistance range in terms of pressure tolerance.
V-Pack packing:
This type of packing, which is also called manual packing in Iran, is usually used in single-row and double-row hydraulic cylinders of weak or strong pressure. This packing includes an upper ring (male support ring) and a lower ring (female support ring) which, depending on the type of pressure that the packing must bear, some other rings (middle rings) are placed in the middle of these two. Mostly, the support rims have a flat surface compared to the middle rims.