Optical Flag Post
Plunger / Piston Assembly - Scribe Marks
Run Area
Pre-Heat
Bushing
2nd Scribe
1st Scribe
Run Start Zone
After melt time (pre-heat) is completed, and after the piston lowers into the
"run area" as denoted by the scribe marks on the piston assembly, make a
cut and press RUN simultaneously. A measurement may start when the 1st
scribe mark has lined up with the top of the guide bushing. The run MUST
start before the 2nd scribe mark lines up with the top of the guide bushing.
See “Making the Cut” section.
If the sample extruded so fast that it has
already passed the scribe marks the user has the following options:
Add more material
Reduce the test load (e.g. 2160 to 225 g)
Reduce the test temperature (e.g. 230 to 190 C)
Use a flow plug
Support the plunger and piston during melt time
Change to a non-standard die (e.g., 1/2 diameter, 1/2 height)
If the sample extrudate is so slow that the first scribe mark is not passed before
8 minutes has expired, the user has the following options:
Add less material
Increase the test load (e.g. 2160 to 21,600 g)
Increase the test temperature (e.g. 190 to 230 C)
Change to a non-standard die (typically larger diameter)
Making the Cut
Weigh the Sample
When the lower scribe mark on the plunger reaches the top of the guide bushing
simultaneously cut the extrudate and press
RUN
. Use the cutting knife in a
wiping like action up against the bottom of the die. After pressing
RUN
a
countdown timer appears on the left of the front display. As it counts down it
will give a warning beep when 10 seconds remain in the cut time. When the
timer reaches zero and the machine beeps, quickly cut the extrudate up against
the bottom of the die.
Weigh the sample and enter the weight in grams using the touch panel and hit
YES
if correct. (A precision balance is needed in order to obtain precise flow
rate measurements) The flow rate will be immediately calculated and displayed.
An extrudate weight of about 1.0 gram or more will reduce weighing errors,
adjust the cut time as needed to get at least 0.5 grams of material.
If the indexer has printing capability, flow rate will be printed along with other
test details. When multiple tests have been completed an average, standard
Series 4000 Melt Indexer Operation Manual
Method "A" Run
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