Nine reasons why hydraulic hoses fail

Key concepts Hose life is cut short by factors that can be controlled. Poor routing is a leading cause of hose failure. Don't operate hoses at their pressure and temperature limits.


Key concepts

Hose life is cut short by factors that can be controlled.

Poor routing is a leading cause of hose failure.

Don't operate hoses at their pressure and temperature limits.

Hoses used in hydraulic systems have a predictable future. They won't last forever.

How do you determine how long a hose will last?

The actual service life of a hose assembly in a given application is determined by a variety of factors. The group of conditions most frequently affecting service life are often called the Notorious Nine .

The impact of the Notorious Nine should be considered at the time of hose installation to help maximize service life. Assistance in analyzing is provided by hose specialists trained to provide professional, knowledgeable advice about the type, style, or application of a hose replacement or installation.

Nine reasons for failure

1. Routing. More than 57% of premature hose failures result from abrasion caused by improper routing. To secure long hydraulic hose life, select and carefully place clamps, route through pivot points, and use protective sleeves (Fig. 1).

2. Operating pressure. Check that the rated maximum operating pressure of the hydraulic hose is greater than the system's operating pressure. Hose lines are rated for continuous operation at their specified maximum operating pressure.

3. Pressure surges. Almost all hydraulic systems develop pressure surges that may exceed relief valve settings. Exposing the hose to surge pressures above the maximum operating pressure shortens hose life. In systems where pressure peaks are severe, select a hose with a higher maximum operating pressure, or choose a spiral reinforced hose specifically designed for severe pulsing applications.

In general, hoses are designed to accommodate pressure surges and have operating pressures equal to 25% of the hose minimum burst pressure.

4. Operating temperatures. Temperature ratings refer to the maximum temperature of the fluid being conveyed. High heat conditions may have an adverse effect on hoses by degrading the rubber, which limits a hose's usefulness. In some cases, fluid being conveyed may slow down degradation, while other fluids may accelerate it. Low temperatures, although a less common concern, should also be taken into consideration, particularly in cold environments.

Continuous use of hoses at maximum temperatures together with maximum pressures should be avoided. Such continuous use causes a deterioration of the physical properties of the inner tube and outer cover of most hoses, reducing the service life.

5. Ambient temperatures. Very high or low ambient temperatures affect cover and reinforcement materials, reducing the life of the hose. Ambient temperatures, in conjunction with internal temperatures, should be considered. This situation can occur in hot process piping operations. For specific recommendations consult the manufacturer.

6. Bend radius. Recommended minimum bend radius is based on maximum operating pressure with no flexing of the hose. Safe operating pressures decrease when the bend radius is reduced below the recommended minimum. Flexing the hose to less than the specified minimum bend radius reduces hose life. The precise bend radius is measured at the inside curvature of the hose and is often difficult to determine (Fig. 2). In general, avoid flattening or kinking any hose.

7. Chemical resistance. Consider the chemical resistance of the fittings, O-rings, hose cover, and inner tube. Covers are designed to resist most common mildew, cleaning solvents, oils, and fuels. Charts detailing the chemical resistance of hose inner tubes, O-rings, and fitting materials are found in manufacturer's handbooks.

8. Vacuum service. Vacuum service is not recommended for double-wire braid or spiral-wire reinforced hose. If vacuum data is not given in a catalog, then the hose is usually not recommended for this type of service.

In addition to specific applications, the pump inlet line of hydraulic systems is frequently subjected to vacuum or negative pressure. Hoses specifically designed for vacuum service have an integral steel coil in the reinforcement lining that does not disrupt fluid flow.

9. Fittings. For any hydraulic hose to be useful, it must have a fitting at each end. In selecting fittings, a decision must be made between crimped and reusable styles. A fittings configuration, as well as a strategic selection of elbows and jump-size components, should be considered for long-life use (Fig. 3). Follow manufacturer's recommendations for fitting assembly procedures.

Even after a thorough analysis of the Notorious Nine factors, hose assemblies in service should be inspected frequently for leakage, kinking, corrosion, abrasion, and any other signs of wear or damage. Hose assemblies that are worn or damaged should be replaced immediately.

Edited by Joseph L. Foszcz, Senior Editor,


This article was prepared from information supplied by Eaton Aeroquip, Maumee, OH.

&HEADLINE>Notorious nine reasons for hose failure&/HEADLINE>

  • Routing


      • Operating pressure


          • Pressure surges


              • Operating temperatures


                  • Ambient temperatures


                      • Bend radius


                          • Chemical resistance


                              • Vacuum service

The Top Plant program honors outstanding manufacturing facilities in North America. View the 2015 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
Doubling down on digital manufacturing; Data driving predictive maintenance; Electric motors and generators; Rewarding operational improvement
2017 Lubrication Guide; Software tools; Microgrids and energy strategies; Use robots effectively
Prescriptive maintenance; Hannover Messe 2017 recap; Reduce welding errors
The cloud, mobility, and remote operations; SCADA and contextual mobility; Custom UPS empowering a secure pipeline
Infrastructure for natural gas expansion; Artificial lift methods; Disruptive technology and fugitive gas emissions
Mobility as the means to offshore innovation; Preventing another Deepwater Horizon; ROVs as subsea robots; SCADA and the radio spectrum
Research team developing Tesla coil designs; Implementing wireless process sensing
Commissioning electrical systems; Designing emergency and standby generator systems; Paralleling switchgear generator systems
Natural gas engines; New applications for fuel cells; Large engines become more efficient; Extending boiler life

Annual Salary Survey

Before the calendar turned, 2016 already had the makings of a pivotal year for manufacturing, and for the world.

There were the big events for the year, including the United States as Partner Country at Hannover Messe in April and the 2016 International Manufacturing Technology Show in Chicago in September. There's also the matter of the U.S. presidential elections in November, which promise to shape policy in manufacturing for years to come.

But the year started with global economic turmoil, as a slowdown in Chinese manufacturing triggered a worldwide stock hiccup that sent values plummeting. The continued plunge in world oil prices has resulted in a slowdown in exploration and, by extension, the manufacture of exploration equipment.

Read more: 2015 Salary Survey

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
The maintenance journey has been a long, slow trek for most manufacturers and has gone from preventive maintenance to predictive maintenance.
Featured articles highlight technologies that enable the Industrial Internet of Things, IIoT-related products and strategies to get data more easily to the user.
This digital report will explore several aspects of how IIoT will transform manufacturing in the coming years.
Maintenance Manager; California Oils Corp.
Associate, Electrical Engineering; Wood Harbinger
Control Systems Engineer; Robert Bosch Corp.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me