Hi Ken:
> The standards specify the oil as being:
> "distillate fuel oil which is a medium volitile distillate having a mass
> per
> unit volume between 0.845 g/ml and 0.865 g/ml, a flash point between 43.5C
> and 93.5C and an average calorific value of 38MJ/l."
I've found that this is equivalent to ordinary
diesel fuel or #2 fuel (heating) oil.
I've bought The tools for performing this test
in almost any kitchen goods store:
all-metal ladle with side-lip (for pouring
the oil)
large aluminum-foil roasting pan (to contain
the poured oil)
I found that the standard kitchen ladle was not
configured for this test, so I chose an all-metal
ladle so I could bend the handle to better suit a
controlled pour.
The height of the ladle above the holes under test
must be controlled to 100 mm. The height is critical
to pass/fail. I found that I could better control
this parameter by using a rest for the ladle handle
adjusted for 100 mm above the holes.
The rate of pour is also critical to pass/fail. You
should practice the pour several times. I found a
big help if someone counted the seconds aloud for me
as I poured. (You can't watch a clock and watch the
pour at the same time!)
The cheesecloth must be located 50 mm below the
openings under test. I found that it was best to
suspend or support the cheesecloth above the bottom
of the pan so as to prevent saturation with the oil
collecting in the bottom of the pan.
I also used a dam of plumber's putty on the test
panel to prevent the oil from spilling over the edge
of the test panel. This helps control spilling the
oil outside the roasting pan.
The test panel needs to be independently supported
and level so as to allow the oil to collect over
the holes.
Note that you are dealing with 3 parameters:
hole diameter
hole-to-hole spacing
metal thickness
All of these are critical to pass/fail.
As near as I can tell, the process of passing the test
is that of cooling the flaming oil by the heat-sinking
action of the metal, and by quenching the flame as the
oil passes through the hole (i.e., the oil fills the
hole such that no oxygen can pass through the hole with
the oil and sustain the burning as the oil emerges from
the bottom of the metal).
Note that you get to repeat the test for a total of 3
successes in succession. Due to the variablility of
the test, if you get some passes and some fails, keep
testing until you get 3 passes in succession! You'll
find that passing is a matter of controlling the test
parameters, especially the location above the holes, the
rate of pour, and the pour height.
Be sure to perform the test in a suitable area such as
a fume hood. Also, be prepared to deal with spilled
oil, and with spilled burning oil. Have someone
standing by with a fire extinguisher at the ready. In
the event of a failure, you'll need it to extinguish
the oil in the pan (otherwise, it will burn for a long
time!).
By the way, the hole patterns (Table 15) specified as
acceptable in the standard do not necessarily pass the
test!
Good luck! Let us know how you do!
Best regards,
Rich
ps: Note that the oil will not ignite at room
temperature. You can dunk a match in the oil,
and the match will be extinguished.
You do need to heat the oil slightly before it
will burn. Don't heat the oil too much -- just
enough to ignite it. Then, you let it burn for
1 minute before the pour; this is all the heat
you want for the oil. Any more, and you'll tend
to fail the test. Be sure to extinguish the
flame you use to heat the oil BEFORE you proceed
with the test.
Disclaimer: The hot-flaming-oil test is a dangerous
test. The preceding comments, observations, and
opinions are not complete, are not necessarily
accurate, may be ambiguous, and must not be
relied upon for the safety of persons conducting
such a test or for the accuracy of the test
results.
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