Earthmoving Equipment, Parts

Tip tips for hose care from Continental

Continental hoses and fittings provide high quality solutions for the toughest applications. To get the most out of your equipment, here are key tips to safely use, store and maintain your hose to maximise its life

Continental hydraulic hoses and fittings have been built to handle the harshest environments across industry – from construction, oil and gas, mining and manufacturing to transportation.

Continental’s crimp fittings provide maximum coupling retention on one- and two-braid hose as well as four- and six-spiral hose. Serrations penetrate the cover with a powerful bite into the wire reinforcement, resulting in even hose compression.

Continental fittings are constructed from a single piece of steel without brazed or welded joints, to provide ultimate protection against leaks and potential leak paths. With full-length crimps and a low-profile design that will last longer, the interlocking Bite-to-Wire technology delivers maximum coupling retention for safer assembly and reliability under the toughest pressure — no internal or external skive required.

To make the most out of your hose and fittings, here are some top tips for hose care and use.

Tips for hose care

Hoses and hose assemblies have a finite life. There are several factors that will reduce hose life.

The maximum operating pressure within the hose should not exceed the recommended working pressure. Burst pressure, which is four times the working pressure, should not be used as the operating pressure of the hose and is for test purposes only. Exposing the hose to pressures higher than the working pressure is dangerous and will shorten hose life.

Exposing the hose to a surge pressure, above the working pressure of the hose, will also shorten hose life. If surges are severe, select a hose with a higher recommended working pressure.

High heat conditions may have an adverse effect on hose due to the degradation of the rubber and the effect on fitting retention. Continuous use at or above the maximum operating temperature of the hose will cause deterioration of the tube, cover and reinforcement, reducing the hose life.

Flexing the hose to less than its recommended minimum bend radius will decrease hose life. Optimise routing to minimise inherent problems. Excessive external forces such as flexing, twisting or kinking will also reduce hose life. Use the correct fitting or adapter to prevent any unnecessary external force.

Consider the chemical resistance of the tube, cover and the fitting, including the O-ring, to maximise hose performance and life. A hose is also designed with a certain level of abrasion resistance, but care should be taken to avoid excessive abrasion, which can damage the hose cover, accelerating hose failure.

The size of the hose assembly components must be adequate to keep pressure losses to a minimum and avoid damage to the hose due to heat generation or excessive turbulence. Also, use the proper end fittings and crimp or install to the proper crimp specification to ensure a safe and proper hose assembly. Make sure that hose fittings are compatible with the hose.

Safety considerations

Fabricators, end users and installers should be aware of the safety factors when handling or in proximity of hydraulic hose assemblies. The following are some potential conditions that can lead to personal injury and property damage.

As certain fluids may permeate the hose cover, the hose should always be used in well-ventilated areas. Any leak of pressurised fluid can penetrate the skin, causing severe tissue damage and burns. Consider the use of guards or shields around the hose assembly to reduce the risk of injury.

Under high operating pressures, the hose and/or fitting can come loose or blow, causing the end of the hose to whip with great force. Again, the hose assembly should be shielded or guarded, even possibly secured, to avoid injury or damage from this whipping action.

Hydraulic fluids are flammable and can explode with a source of ignition. To avoid possible injury or property damage, care should be taken to eliminate ignition sources and to properly route the hose assembly to minimise the chance of combustion.

In some cases a nonconductive hose is required. To avoid electrocution or other serious mishap, the correct hose specification, either conductive or non-conductive, should be used.

Should a hydraulic hose assembly fail, loss of hydraulic pressure will impact the operation of equipment. Care should be taken that a sudden power loss to the equipment will not cause personal injury.

When air or gaseous materials are being conveyed, the correct hose should be used. A pin-perforated cover may be required. Perforations in the cover will prevent permeated gasses from accumulating and blistering the cover.

Extreme care should be used when operating handheld hydraulic tools where the operator is in proximity to the hydraulic hose assembly. The following steps should be taken to avoid injury:

  • use strain relievers on each end of the hose to prevent kinking, excessive bending or stress on the hose at the coupling;
  • never use the hose assembly to pull or carry the tool;
  • exposed hose near the operator should be guarded in case the hose assembly fails, to prevent injury from high-pressure or high-temperature fluid;
  • operators of the tool should be protected with the required safety clothing, considering the job and fluids being used; and
  • the hose should be protected against any external damage.

Hose maintenance

To reduce equipment downtime and maintain peak operating performance of the hydraulic system, hose assemblies should be inspected on a regular basis with a frequency based on the prior history of the equipment, a set maintenance/inspection program and the severity of the application or risk potential.

Hose or fittings that are corroded or broken, leaking or cracked should be replaced immediately. Inspectors should also look for missing clamps, guards or shields as well as excessive dirt or grease or contamination and air entrapment.

If the hose assembly can be inspected and detached from the hydraulic system, the assembly can be cleaned by blowing it out with clean, compressed air or by rinsing it with a compatible cleaning fluid.

The hose assembly should be hydrostatically tested, using the approved test stands and procedures as outlined in SAE J517. Test at proof pressure, or twice the working pressure of the hose, for 30 seconds to one minute. When test pressure is reached, visually inspect the hose for any signs of weakness, leaks or any hose movement relative to the fitting that would indicate a loose fitting. If any of these conditions exist, the assembly should be replaced.

Temperature, humidity, ozone, sunlight, oils, solvents, corrosive liquids, insects, rodents and radioactive materials can adversely impact hose products. Hoses should be stored in a dark, dry atmosphere away from heat sources, electrical equipment and the above adverse elements. The ideal storage temperature for rubber hose is 50°F to 70°F (10°C to 21.1°C), with a maximum of 100°F (37.8°C).

For more information on Continental’s range of hose and fitting solutions, visit: www.continental-industry.com

Send this to a friend