MACS Monthly Newsletter - 2021 - AUG4

SAMPLE CONDITIONING
Both SAE J3062 and SAE J2064 require that hose or
hose assemblies be pre-conditioned. Prior to testing
samples charged with refrigerant, they must first be stabilized
for both time and temperature as described in
each of the standards. The procedure varies depending
upon the hose type.
PERMEATION TEST
One of the most important functions of automotive
and mobile air-conditioning hose is to contain the refrigerant
charge in the system. Hose by design is not
" hermetic " in its ability to contain the refrigerant. It is,
however, designed to contain the refrigerant charge by
minimizing permeation through the layers of the hose.
Hose intended for usage on the high side of the system
are Types C, D, E, F, G hose constructions. Each of these
hose designs include a layer, normally of thermoplastic
material, to minimize refrigerant permeation. Hose intended
for usage on the low side of the system are normally
Type A or B hose constructions. These hose types
do not include a thermoplastic barrier layer but must be
tested and meet requirements for refrigerant permeation
which are different than the requirements for the high
side hoses.
Both SAE J3062 and SAE J2064
Figure 3: Permeation
/ Coupling
Integrity Test Assembly.
require
that hose or hose assemblies
pass a refrigerant permeation
test. Figure 3 illustrates an example
of a permeation test assembly. The
permeation assembly consists of a
container (optional) and fitting for
charging the test assembly with
refrigerant to perform the test. The
exposed hose must be at the predetermined
length as specified in
the standards. If the test is being
performed to SAE J2064, the test assembly
must include factory or field
coupled hose fittings and crimping
tools (commonly referred to as
production intent). There is a predetermined
length of exposed hose
which will be tested for refrigerant
loss permeation (loss).
Test samples charged with refrigerant are placed in a
constant temperature oven for a duration of 25 days. Figure
4 is an example of a laboratory with several laboratory
ovens large enough to perform constant temperature
testing. The test temperature is 80 °C ± 2 °C.
Refrigerant loss is determined by the procedure listed
in the SAE standards. The allowable refrigerant loss is
dependent upon the type of hose construction being
tested. Tables are included in each of the SAE standards
which show the refrigerant permeation limits for each
hose type and refrigerant.
August 2021
4
Figure 4: Constant Temperature Chamber.
COUPLING INTEGRITY
Both SAE J3062 and SAE J2064 require that hose or
hose assemblies pass a Coupling Integrity Test. If the
test is being performed to SAE J2064, the test assembly
must include factory or field coupled hose fittings and
crimping tools. Although this test is intended to evaluate
the quality (integrity) of a hose assembly, it is also inFigure
5: Thermal Cycle Chamber.
MACS Service Reports
Gene Dianetti
Gene Dianetti
Gene Dianetti
MACS Monthly Newsletter - 2021

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