The hydraulic hose can be classified into four categories according to the operating pressure:
1. Compression fitting (without clamp)
• Appropriate for low-pressure (less than 20 bar) applications
•The possibility of installation with compression fitting without a fastener for the hose joint.
2. Low pressure
• Having one or two layers of yarn with a layer of steel wire
3. Medium pressure
Having one or two layers of steel wire
4. High pressure
• Having four or six layers of steel wire
The pressure that the hose is designed to operate in that range. A well-known unit for pressure is a bar.
The least pressure at which a piece of hose bursts, meaning that if we select and test several specimens of a particular hose, the minimum bursting value is cited.
The internal diameter of the hose applied to measure the hose size. Hose size is normally expressed in inches.
Minimum bending radius:
The minimum radius at which a hose can be bent. The hydraulic hose is designed to make joints between parts that are moving relative to each other. Therefore, the "bending radius" is a major factor in choosing a hose. As the inner tube and hose surface is stretched and hence thinned during bending, the resistance of the hose against pressure is greatly diminished.