Appendix A (Sae J1273 May 1988) - FCI RHCC129ACSR Instrucciones De Seguridad, Funcionamiento Y Mantenimiento

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APPENDIX A
SELECTION, INSTALLATION AND MAINTENANCE OF
HOSE AND HOSE ASSEMBLIES
SAE J1273 MAY 1986*
SAE RECOMMENDED PRACTICE
The following recommendations on selection, installation
and maintenance of hose and hose assemblies were
established by SAE in 1979 and reaffirmed May 1986.
Please read these general instructions carefully.
1. SCOPE
Hose (also includes hose assemblies) has a finite life
and there are a number of factors which will reduce its
life.
This recommended practice is intended as a guide to
assist system designers and/or users in the selection,
installation and maintenance of hose. The designers and
users must make a systematic review of each application
and then select, install and maintain the hose to fulfill the
requirements of the application. The following are general
guidelines and are not necessarily a complete list.
Improper selection, installation, or maintenance may
result in premature failures, bodily injury, or property
damage.
2. SELECTION
The following is a list of factors which must be considered
before final hose selection can be made.
2.1 Pressure - After determining the system pressure,
hose selection must be made so that the
recommended maximum operating pressure is
equal to or greater than the system pressure. Surge
pressures higher than the maximum operating
pressure will shorten hose life and must be taken
into account by the hydraulic designer.
2.2 Suction - Hoses used for suction applications must
be selected to insure the hose will withstand the
negative pressure of the system.
2.3 Temperature - Care must be taken to insure that
fluid and ambient temperatures, both static and
transient, do not exceed the limitations of the hose.
Special care must be taken when routing near hot
manifolds.
2.4 Fluid Compatibility - Hose selection must assure
compatibility of the hose tube, cover, and fittings
with the fluid used. Additional caution must be
observed in hose selection for gaseous
applications.
* Reprinted with permission from SAE J1273 ©1991. Society of Automotive Engineers.
2.5 Size - Transmission of power by means of pressurized
fluid varies with pressure and rate of flow. The size
of the components must be adequate to keep
pressure losses to a minimum and avoid damage
to the hose due to heat generation or excessive
turbulence.
2.6 Routing - Attention must be given to optimum routing
to minimize inherent problems.
2.7 Environment - Care must be taken to insure that the
hose and fittings are either compatible with or
protected from the environment to which they are
exposed. Environmental conditions such as
ultraviolet light, ozone, salt water, chemicals, and
air pollutants can cause degradation and premature
failure and, therefore, must be considered.
2.8 Mechanical Loads - External forces can significantly
reduce hose life. Mechanical loads which must be
considered include excessive flexing, twist, kinking,
tensile or side loads, bend radius, and vibration.
Use of swivel type fittings or adapters may be
required to insure no twist is put into the hose.
Unusual applications may require special testing
prior to hose selection.
2.9 Abrasion - While a hose is designed with a
reasonable level of abrasion resistance, care must
be taken to protect the hose from excessive
abrasion which can result in erosion, snagging, and
cutting of the hose cover. Exposure of the
reinforcement will significantly accelerate hose
failure.
2.10 Proper End Fitting - Care must be taken to insure
proper compatibility exists between the hose and
coupling selected based on the manufacturer's
recommendations substantiated by testing to
industry standards such as SAE J517d (November,
1976).
2.11 Length - When establishing proper hose length,
motion absorption, hose length changes due to
pressure, as well as hose and machine tolerances
must be considered.
2.12 Specifications and Standards - When selecting
hose, government, industry, and manufacturer's
specifications and recommendations must be
reviewed as applicable.
2.13 Hose Cleanliness - Hose components vary in
cleanliness levels. Care must be taken to insure
that the assemblies selected have an adequate
level of cleanliness for the application.
2.14 Electrical Conductivity - Certain applications require
that the hose be non-conductive to prevent
electrical current flow. Other applications require
the hose to be sufficiently conductive to drain off
static electricity. Hose and fittings must be chosen
with these needs in mind.