Installation Specifications For Hydraulic Hoses
Dec 10, 2025| Pre-Installation Preparation
1.Correct Selection: Ensure the hose assembly (type, diameter, length, fitting style) matches the system's design pressure, temperature, and media compatibility, and conforms to drawing requirements.
2.Cleaning and Inspection:
- Clean Lines: Blow out metal chips, dust, and other contaminants from pipe fittings and hard lines using compressed air or nitrogen.
- Inspect Hose Assembly: Verify the hose has no manufacturing defects (e.g., bulges, cuts), fittings have no burrs or corrosion, and threads are intact. Check the "Manufacture Date" to ensure the hose has not exceeded its shelf life (typically 4-6 years, even if unused).
3.Length Verification: The hose should remain slack after installation, not taut. Length must account for hose contraction/expansion due to system pressure changes, oil temperature changes, and equipment movement travel.
Key Installation Specifications
Avoid twisting : Hydraulic hoses should be avoided from twisting during installation, as twisting can significantly shorten the hose's service life. Tests show that a mere 7° torsion of the hose can reduce its service life by 80% .
Reserve allowance : When installing the hose, a certain length allowance should be reserved to cope with the expansion and contraction of the hose under pressure changes. It is usually recommended to leave a margin of about 3% to 5% .
To meet the bending radius requirement : the bending radius of the hose should be no less than 8 to 10 times the outer diameter of the hose to avoid tearing the reinforcing metal wire braided fabric. At the same time, the roots of the joints at both ends of the hose are not allowed to be bent. A certain straight section should be reserved, and its length shall not be less than 6 times the outer diameter of the hose .
Correctly determine the length of the hose : The selection of the hose length should take into account its elasticity and avoid being too long or too short. A hose that is too long will increase unnecessary costs, while one that is too short may break due to the lack of sufficient expansion space .
Avoid twisting the hose : For hoses bent in the same plane, when there is relative motion between the two connected components, twisting the hose should be avoided to reduce the impact on the hose's pressure-bearing capacity .
Precautions for installing pipe clamps : When the hose is under pressure, pipe clamps should not be set at bends. They should be allowed to move freely. The pipe clamp should be set in the straight section to ensure that the hose will not be damaged by the pipe clamp when under pressure.
Keep away from heat sources : When installing hydraulic hoses, they should be kept away from heat sources such as diesel engine exhaust pipes to prevent the hoses from aging or being damaged due to high temperatures .
Post-Installation Inspection and Testing
1. Visual Inspection: Confirm all installation specs are met (no twist, proper bend, slack, protection, etc.).
2. Pressure Test:
- Perform a leak test with gradual pressure increase.
- Hold pressure at 1.5 times working pressure (not exceeding hose rated pressure) for several minutes Check all fittings and the hose body for leaks, abnormal bulging, or distorted.
3. Trial Run: Start the equipment at low speed/pressure, cycle several times to purge air. Then gradually increase to operating pressure, observing the hose condition under dynamics.
4. Labeling: Attach/bind a tag on or near the assembly noting key info (e.g., pressure, date, ID number) for future maintenance and life management.