The safest, highest quality hydraulic hose assemblies are made with hoses, fittings and crimping equipment from the same manufacturer. Components from different manufacturers should not be used when making hose assemblies (apart from rare instances when both manufacturers have approved the exception). Installing fittings from different manufacturers can cause coupling retention to be adversely affected. For instance, mixing and matching components can lead to hoses bursting, couplings leaking and blown-off ends maiming or even killing workers. Thread or flange ends must also be properly matched to their mating components to create leak-proof connections. In addition to the dangers involved, mixing and matching brand names will void the manufacturer’s warranty and could also exclude manufacturers from liability should someone get injured by a failed hose assembly.
It is important to remember that an individual is solely responsible for the hose assemblies he or she fabricates. Mixing and matching components can potentially expose that person and their employer to liability claims if an assembly fails. The following advisory from Parker addresses common causes, misconceptions, consequences, and costs of incompatible hydraulic hose assemblies.
Generic, look-alike and/or "knock-off" hoses and fittings have become more prevalent in the marketplace in recent years. Be certain to correctly identify components before introducing them into a hydraulic system. Laylines on hoses and stampings on fittings designate, among other things, manufacturer, type, size, working pressure, and age. Never use a hose or fitting of unknown capability or origin.
Correction: While manufacturers’ fittings may look similar, they likely have not been approved for use on a different manufacturer’s hose. Parker, for instance, subjects its fittings to a substantial number of testing and qualification procedures prior to approving them for use on a particular hose. It is important to note that SAE and NAHAD also indicate that it is extremely important that the specific instructions of the hose and coupling manufacturers be followed. The intermixing of hose and couplings from different manufacturers is not typically acceptable. Couplings are engineered to only work with approved hoses and vice-versa. Do not use hose/coupling combinations that are not approved by the manufacturer. If the hose and coupling are supplied by different manufacturers, then both must approve of their use together. In no instance should the information printed in this section supersede a manufacturer's instructions.
Correction: Only use the specific hose and fitting combinations that have been tested together as an assembly in accordance with the industry specification. The fitting, unless qualified by its manufacturer (then also by the hose manufacturer) for use with a particular hose, should not be used.
Correction: A manufacturer’s formal crimp specifications rarely, if ever, support different manufacturers’ hose, fitting, and crimper combinations. Only crimp hoses and fittings with equipment approved by the manufacturer of the hose and fitting. Please reference Parker Crimpsource for Parker’s crimp specifications as well as compatible hose and fitting combinations.
To mix and match components is to increase the risk of hose failure – a dangerous situation regardless of setting or application. Possible consequences of hose failure resulting from the use of incompatible components include:
Fittings are thrown off at high speed,
High-velocity fluid discharge,
Fluid injection injury,
Violently "whipping" hose,
Sparking or explosion from sprayed flammable fluids, and
Suddenly moving/falling objects otherwise held static by fluid pressure.
Hose failure is also expensive for those who sell assemblies or rely on them to get the job done. The high cost of hose failure can include:
Subsequent machine and/or system damage
Medical bills/increased insurance premiums
Parker’s recommendations are consistent with SAE standard J1273: Industry Consensus on Best Practices for Using Hydraulic Hose. The complete technical paper, which includes SAE-recommended practices for hose assembly fabrication, can be purchased from www.SAE.org.
Article contributed by Kyri McDonough, marketing services manager at Hose Products Division, Parker Hannifin.
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