Safety is of utmost concern when it comes to hydraulic systems, including the selection process, maintaining and replacing hoses. Hydraulic hoses are going to a cylinder that distributes power. So, if a hose fails when someone is using a bucket on a loader, the cylinder can make the bucket close or it can dump its contents unexpectedly. If it's a high-lift application, safety is of greater concern.
Although establishing and maintaining a safe work environment might seem like common sense, refreshing associates and employees on the basics will help lessen the risk of catastrophic outcomes. Maintenance routine, leaks, contamination, temperature and pressure ratings are all factors to consider when working with hydraulic equipment.
Safety and maintenance tips to establish in your facility
- Have a maintenance routine
Checking hoses on a monthly basis is an easy way to catch issues with your hydraulic hose assemblies that may cause larger issues in the future. Creating and strictly following a maintenance plan takes time and will take some getting used to. If you stick with it, frequently checking hoses will prevent your equipment from lengthy and expensive downtime. Hydraulic equipment that is taken care of will likely last longer. An asset tagging and identification system, similar to Parker Tracking System (PTS), is an efficient way of creating a maintenance routine.
PTS helps customers reduce equipment and machinery downtime by increasing the speed, timing and accuracy of maintaining hose assembly information by using a unique identification code. Reporting tools also assist in the continuous improvement programs and preventative maintenance initiatives.
QUICK TIP: Before cleaning an oil spill, always check EPA, state and local regulations.
- Don’t ignore leakage
External leakage means there is something wrong. Hydraulic oil is expensive on its own, however if a leak is large enough, OSHA and EPA fines along with clean-up will only add to that cost. Furthermore, there is a substantial safety concern because a machine operator or technician can easily slip and fall on the remnants of a leaking hydraulic system. Pressurized hydraulic fluid also presents a considerable fire risk whenever threaded pipe connectors, valve seals and flexible hoses rupture or vibrate loose. This risk is especially high when the machine operates in an environment where ignition sources are constantly present, such as plastics forming, die casting, etc.
- Replace old or damaged assemblies
Learn to identify potential hazards. Look for cracks, abrasions in the cover, tight bends or twisting. The cover protects the reinforcements (wire or fabric) from weather and environmental hazards such as rocks. If the wire or fabric is exposed, water and debris can adversely affect the reinforcement by either rusting the wire or, in the case of fabric, allowing water to wick into the system and get behind the coupling where it can cause damage. Also check to see if the hose is twisted. Look for any seepage in the area of the coupling or on the hose and any bubbling on the cover. In extremely abrasive situations or in areas where you simply can't get away from abrasion points, consider hoses with special coverings, such as Parker’s hose guards. Be aware that if you utilize nylon sleeves for abrasion resistance, you can still see abrasion beneath the cover and, in some cases, the sleeve may actually cause the abrasion.
- Prevent Contamination
When replacing a hose assembly, be sure that it has been properly cleaned before putting it on your hydraulic equipment. If the fluid going through your hydraulic hose carries debris, it can wear away the inner tube, eventually leading to another failed hose assembly. To remove contamination, pellet flush the hose with Parker’s Hose Cleaning Kit. Once assembled, cap assemblies with Parker Clean Seal to prevent recontamination during transportation. In the end, the dirt won't harm the hose, but if it reaches the valves, cylinders and pumps, that's when problems occur.
- Maintain the correct temperature
The hydraulic fluid temperature should be within the specified temperature of the hose. The temperature ratings are there for a reason and are different for each hose. Be sure to check the temperature rating of your specific hose by either looking on the hose layline, visiting Parkerhose.com or by looking in your Hose Products Division catalog. If the fluid temperature rises above the working temperature of the hose, small cracks will form on the inner tube and the hose will lose its flexibility.
QUICK TIP: Is your hose hot to the touch? If you can’t hold it for five seconds, the operating temperature may be too high.
- Don’t exceed pressure ratings
The pressure ratings of the hose should not be exceeded. Although hoses are tested to higher pressures, it is for your safety and the hose life to use as recommended. Pressure ratings can be found in the engineering specifications for each hose and the hose overview chart. Using higher pressures than recommended will result in a shorter hose life and potentially dangerous conditions.
QUICK TIP: The typical safety factor is "4 times." Thus, a component rated to 5,000 psi must have an average burst pressure exceeding 20,000 psi.
- Compete a hose failure analysis
If a hose fails, have it tested to see why. You won’t be able to prevent the same issues from happening in the future if you don’t know what caused it in the first place. Fixing the root cause will save a tremendous amount of time and money. Hoses manufactured by Parker’s Hose Products Division can be returned for investigation of the failure by filling out the Technical Problem Checklist form.
Why begin a maintenance program?
From cost savings to protecting workers, every organization has much to gain from a solid preventive maintenance program. Here are some examples:
- Efficient production, since equipment is in prime operating condition.
- Better use of in-shop maintenance personnel with less emergency work.
- Improved control of spare parts inventory and reduced parts usage.
- Less equipment downtime through scheduled inspections.
- Safety hazards are minimized.
- Increased life expectancy of equipment.
- Fewer capital outlays for premature purchases of new equipment.
- Reduced repair costs from fewer breakdowns.
As you know, hoses are only a small part of hydraulic equipment and machinery, however they can be the cause of some of the largest problems as well as serious injury if not maintained.
Article contributed by Kyri McDonough, marketing services manager at Hose Products Division, Parker Hannifin.
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