D92_A1 (16b)
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Test cup conforming to
figure 3 with dimensions
as shown with the figure--
the cup shall be made of
brass or other non-rusting
metal of equivalent
heat conductivity.
The cup may be
equipped with a handle.
The heating plate shall
be of sufficient dimension
and materials to ensure that
thermal heat to the test cup
is only applied to the
bottom of the test cup,
and that extraneous heat to
the test cup other than that
to the bottom is minimized.
An example for manual apparatus
that utilize Bunsen burners
or exposed electric heating
elements is shown in figure 2.
Ignition source
applicator-- the device
for applying the test flame
may be of any suitable type.
When using a test
flame, it is suggested
that the tip be 1.6 plus
or minus 0.05 millimeters,
or 1/16 of an inch, in
diameter at the end,
and that the orifice be
approximately 0.8 plus or minus
0.05 millimeters, or 1/32
of an inch, in diameter.
The device for operating
the test flame applicator
may be mounted in
such a manner as
to permit automated duplication
of the sweep of the test flame,
the radius of swing being not
less than 150 millimeters,
or 6 inches.
The center of the
test flame should
be supported so that
it swings in a plane
not greater than 2 millimeters,
or 5/64 of an inch,
above the plane of
the rim of the cup.
It is desired that a
bead having a diameter
of 3.2 to 4.8 millimeters,
or 1/8 to 3/16 of an inch,
be mounted in a convenient
position on the apparatus
so that the size of the test
flame can be compared to it.
A test flame relighting
device such as a pilot flame
is sometimes used to
automatically relight
the test flame in
the event that it is
extinguished during the test.
This device should
be designed such
that the unburned gas will not
spread out over the test cup
during the relighting.
Heater-- heat may be supplied
from any convenient source.
The use of a gas burner or
alcohol lamp is permitted,
but under no
circumstances are products
of combustion or free
flame to be allowed
to come up around the cup.
An electric heater which can
be controlled automatically
or controlled by the
user is preferred.
The source of the
heat shall be centered
under the opening
of the heating plate
with no local superheating.
Flame-type heaters
may be protected
from drafts or
excessive radiation
by any suitable type
of shield that does not
project above the level of the
upper surface of the heating
plate.
Temperature measuring
device support--
any convenient device that will
hold the temperature measuring
device in a specified
position during a test
and that will permit easy
removal of the temperature
measuring device from the test
cup upon completion of the test
may be used.
Heating plate support--
any convenient support
that will hold the heating
plate level and steady
may be employed.