Hydraulic hoses are common, medium-life consumables on construction machinery. Their lifespan depends on:

• Product quality

• Hydraulic oil cleanliness

• Installation method (length, bend radius, avoiding twists)

• Working environment (temperature extremes: high heat, cold regions, etc.)

Choosing hoses involves balancing cost and performance. For example, hoses rated for cold climates have good flexibility, anti-hardening, and weather resistance. But manufacturers must balance cost and performance carefully—focusing on only one factor is not sufficient.

Key Considerations for Hose Assemblies

A hydraulic hose assembly is usually delivered ready to install, but it’s wise to perform a basic inspection of the crimping process, which affects reliability and lifespan:

1. Check the fitting quality first

   • Ensure fittings come from reliable brands.

   • Inspect the crimping machine’s dies and determine the correct crimping pressure based on hose diameter.

   • Neglecting this step reduces hose life and increases maintenance cost.

2. Understand fitting material and thickness

   • The thickness and material of the fitting directly affect crimp quality.

   • Proper crimp pressure ensures the hose does not detach during operation.

3. Avoid excessive crimping pressure

   • Too much pressure deforms the hose’s inner diameter, causing reduced flow or blockage.

   • Pilot lines and small-diameter hoses are especially vulnerable.

   • Cut open hoses with improper crimping often show polygonal inner diameters or crushed sections.

   • Ideal crimping pressure depends on the fitting’s material and wall thickness; improper crimping is a major source of leakage.

4. Crimping method (die structure) matters

   • The shape and length of the crimp die affect hose performance.

   • If the die is too long or poorly shaped, the crimp pressure is unevenly applied, reducing the bond between hose and fitting.

   • Over-crimping can shift stress from thick-wall areas to thin-wall sections, deforming the hose internally and shortening service life.

Practical Insights

• Hydraulic hose cost is small compared to potential hydraulic oil losses from leakage—losses can be substantial even if the machine is shut down a few seconds late.

• High-quality dies may be more complex to manufacture, but they ensure reliable hose assemblies without additional cost.

• Even some “original equipment” hoses may have subpar crimping—check carefully.

• Experienced technicians can reuse fittings with proper tools, even decades after first installation.

Bottom Line

By examining a machine’s hydraulic hose assemblies and their crimp quality, you can assess:

• The supplier’s overall quality control

• Whether the hose will perform reliably

• How likely it is to leak or fail early

This attention to detail often resolves recurring hose leaks and avoids costly hydraulic oil losses, as evidenced by your experience resolving multiple leaks in refurbished machines.

If you want, I can also make a quick “Hydraulic Hose Crimping Checklist” for field operators so that anyone inspecting hoses can follow it step by step and avoid failures.