When will my hose assembly fail? This may be the most common question when talking about hose assembly replacement. Sometimes hose assembly failures can cause serious damage and lead to costly downtime. Knowing what can cause a failure and having the exact hose replacement on hand will help you be prepared.
The surprise of a hose assembly replacement can be reduced by implementing a preventative maintenance schedule and by knowing how to recognize hose wear. There are several common factors that may cause problems with your hose assembly, you should look for these during your routine inspections.
1. Abrasion - Excessive rubbing of the hose against an external object or even another hose can wear away the cover and eventually the reinforcement layers. The cover is meant to protect the hose from the environment, so signs of damage to the cover or reinforcement layers should warn that failure is imminent.
2. Minimum bend radius - Hose assemblies can fail relatively quickly if the minimum bend radius is exceeded. For high pressure applications, premature failure could occur due to increased stress on the hose. In vacuum or suction applications, if the bend radius is exceeded, the hose may tend to be flat in the bend area. This will hinder or restrict flow. If the bend is severe enough, the hose may kink.
3. Heat aged - Overheating, from the internal hydraulic oil temperature or the external ambient temperature, will cause the hose to become very stiff. Overheating is accelerating when there is a hot internal fluid temperature and a hot external temperature. The inner tube will harden and begin to crack because the plasticizers in the elastomer will break down or harden under high temperatures. In some cases, the cover may show signs of being dried out.
4. Improper assembly - Contamination can be a result of poor assembly practices and can cause several problems for a hydraulic hose assembly. When cutting a hose, metal particles and debris can settle inside the hose if not properly flushed. This abrasive debris left in the hose will contaminate the hydraulic system. It can also cause small fractures to develop on the inner tube of the hose assembly, resulting in leakage.
5. Fluid compatibility - Incompatible fluids will cause the inner tube of the hose assembly to deteriorate, swell, and delaminate, The inner tube can also partially wash out in some cases. Verify that the fluid is not only compatible with the inner tube, but also the outer cover, fittings, and even O-rings.
6. Insertion depth - Fittings need to be pushed on completely to meet the recommended insertion depth. If the hose insertion depth is not met, fittings can blow off, leaving a failed hose assembly. The last grip in the fitting shell is essential to the holding strength.
7. Dry air / aged air - To avoid dry or aged air problems, confirm your hose is rated for extremely dry air. Hoses with inner tubes of PKR or EPDM rubber are preferred for these applications.
8. Tube erosion - Tube erosion is usually caused by a concentrated high-velocity stream of fluid or by small particles in the fluid. A hose assembly that is bent too tight for flow or an over abrasive medium for the inner tube can also lead to erosion.
Your maintenance schedule should include checking hoses monthly, it is an easy way to catch issues with your hydraulic hose assemblies that may cause larger issues in the future. If you stick with it, frequently checking hoses will prevent your equipment from lengthy and expensive downtime.
The other piece of the puzzle is knowing the specifications of the hose assembly that needs to be replaced. Parker’s asset tagging and identification system, Parker Tracking Systems (PTS), is an efficient tool that can be integrated into your maintenance plan. Each PTS tagged hose assembly has a unique tracking number that provides the details of the hose assembly, so the PTS tagged hose assembly can be ordered without having to remove the part. PTS eliminates the need to wait for removal before the new part can be acquired. By reducing transaction time, customers can realize significant gains in productivity and increases invaluable up-time.
Parker hydraulic hose replacement is easier than ever when you order your PTS tagged hose assembly online. Your PTS tag includes all of the configuration specifications you need.
Ordering is easy, start with your PTS ID number and have your hose replacement shipped to you.
Learn more about ordering hose assemblies online from Parker. Be prepared, hydraulic equipment that is taken care of will likely last longer.