Rubber hydraulic hose and ... - Flipbook - Seite 294
Safety information | Danfoss
General hose selection information
Selection, installation and maintenance
of hose and assemblies
The following recommendations on selection, installation and maintenance of hose assemblies were established in
SAE J1273. Please read these general instructions carefully. More detailed information on many of these subjects is
covered in this catalog.
4.1 Pre-installation inspection
Prior to installation, a careful examination of the
hose must be performed. All components must
be checked for correct style, size and length. In
addition, the hose must be examined for cleanliness, I.D. obstructions, blisters, loose cover, or
any other visible defects.
4.2 Follow manufacturers’
assembly instructions
Hose assemblies may be fabricated by the
manufacturer, an agent for or customer of
the manufacturer, or by the user. Fabrication
of permanently attached fittings to hydraulic
hose requires specialized assembly equipment.
Field attachable fittings (screw style and segment clamp style) can usually be assembled
without specialized equipment although many
manufacturers provide equipment to assist in the
operation.
SAE J517 hose from one manufacturer is usually
not compatible with SAE J516 fittings supplied
by another manufacturer. It is the responsibility
of the fabricator to consult the manufacturer’s
written assembly instructions or the manufacturers directly before intermixing hose and fittings
from two manufacturers. Similarly, assembly
equipment from one manufacturer is usually not
interchangeable with that of another manufacturer. It is the responsibility of the fabricator to
consult the manufacturer’s written instructions
or the manufacturer directly for proper assembly
equipment. Always follow the manufacturer’s
instructions for proper preparation and fabrication
of hose assemblies.
4.3 Minimum bend radius
Installation at less than minimum bend radius may
significantly reduce hose life. Particular attention
must be given to preclude sharp bending at the
hose/fitting juncture.
4.4 Twist angle and orientation
Hose installations must be such that relative motion of machine components produces bending
of the hose rather than twisting.
4.5 Securement
In many applications, it may be necessary to restrain, protect, or guide the hose to protect it from
damage by unnecessary flexing, pressure surges,
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and contact with other mechanical components.
Care must be taken to insure such restraints do
not introduce additional stress or wear points.
4.6 Proper connection of ports
Proper physical installation of the hose requires a
correctly installed port connection while insuring
that no twist or torque is put into the hose.
4.7 Avoid external damage
Proper installation is not complete without
insuring that tensile loads, side loads, kinking,
flattening, potential abrasion, thread damage,
or damage to sealing surfaces are corrected or
eliminated.
4.8 System check out
After completing the installation, all air entrapment
must be eliminated and the system pressurized to
the maximum system pressure and checked for
proper function and freedom from leaks.
NOTE: Avoid potential hazardous areas
while testing.
5. Maintenance
Even with proper selection and installation, hose
life may be significantly reduced without a continuing maintenance program. Frequency should
be determined by the severity of the application and risk potential. A maintenance program
should include the following as a minimum.
5.1 Hose storage
Hose products in storage can be affected
adversely by temperature, humidity, ozone,
sunlight, oils, solvents, corrosive liquids and
fumes, insects, rodents and radioactive materials.
Storage areas should be relatively cool and dark
and free of dust, dirt, dampness and mildew.
5.2 Visual inspection
Any of the following conditions requires
replacement of the hose: Leaks at fitting or in
hose (leaking fluid is a fire hazard). Damaged, cut,
or abraded cover (any reinforcement exposed)
Kinked, crushed, flattened, or twisted hose
Hard, stiff, heat cracked or charred hose
Blistered, soft, degraded, or loose cover
Cracked, damaged, or badly corroded fittings
Fitting slippage on hose
EMEA Danfoss rubber hydraulic hose, fitting, tooling and accessories category catalog
5.3 Visual inspection
The following items must be tightened,
repaired, or replaced as required:
Leaking port conditions
Clamps, guards, shields
Remove excessive dirt buildup
System fluid level,fluid type, and any air entrapment
5.4 Functional test
Operate the system at maximum operating pressure and check for possible malfunctions and
freedom from leaks.
NOTE: Avoid potential hazardous areas
while testing.
5.5 Replacement intervals
Specific replacement intervals must be considered based on previous service life, government
or industry recommendations, or when failures
could result in unacceptable down time, damage,
or injury risk.
