ASTM D3123-98(2004)
(Test Method)Standard Test Method for Spiral Flow of Low-Pressure Thermosetting Molding Compounds
Standard Test Method for Spiral Flow of Low-Pressure Thermosetting Molding Compounds
SIGNIFICANCE AND USE
The spiral flow of a thermosetting molding compound is a measure of the combined characteristics of fusion under pressure, melt viscosity, and gelation rate under specific conditions.
This test method is useful as a quality control test and as an acceptance criterion.
This test method, by itself, is not a valid means for comparing the moldability of similar or different molding compounds because it cannot duplicate actual conditions prevalent in different types of production molds.
This test method is presently intended for use at a transfer pressure of 6.9 MPa [1000 psi] and a mold temperature of 423 ± 3 K (150 ± 3°C [302 ± 5°F]).
SCOPE
1.1 This test method covers a procedure for measuring the spiral flow of thermosetting molding compounds (soft or very soft) designed for molding pressures under 6.9 MPa [1000 psi]. It is especially suited for those compounds that may be used for encapsulation or other low pressure molding techniques. Textile-reinforced compounds should not be tested using this test method. It involves the use of a standard spiral flow mold in a transfer molding press under specified conditions of applied temperature and pressure with a controlled charge mass.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.Note 1
There is no equivalent ISO standard.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D3123–98 (Reapproved 2004)
Standard Test Method for
Spiral Flow of Low-Pressure Thermosetting Molding
Compounds
This standard is issued under the fixed designation D 3123; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope* 4.2 This test method is useful as a quality control test and as
an acceptance criterion.
1.1 This test method covers a procedure for measuring the
4.3 This test method, by itself, is not a valid means for
spiral flow of thermosetting molding compounds (soft or very
comparing the moldability of similar or different molding
soft)designedformoldingpressuresunder6.9MPa[1000psi].
compounds because it cannot duplicate actual conditions
Itisespeciallysuitedforthosecompoundsthatmaybeusedfor
prevalent in different types of production molds.
encapsulation or other low pressure molding techniques.
4.4 This test method is presently intended for use at a
Textile-reinforced compounds should not be tested using this
transferpressureof6.9MPa[1000psi]andamoldtemperature
test method. It involves the use of a standard spiral flow mold
of 423 6 3 K (150 6 3°C [302 6 5°F]).
in a transfer molding press under specified conditions of
applied temperature and pressure with a controlled charge
5. Apparatus
mass.
5.1 Transfer Molding Press with a minimum 150 by
1.2 This standard does not purport to address all of the
150-mm [6 by 6-in.] platen area, transfer piston pressure
safety concerns, if any, associated with its use. It is the
potentially greater than 6.9 MPa [1000 psi], sufficient clamp
responsibility of the user of this standard to establish appro-
pressure to prevent flashing, and a minimum plunger speed of
priate safety and health practices and determine the applica-
25.4 mm [1 in.]/s without load. The plunger should be
bility of regulatory limitations prior to use.
equipped with at least one peripheral sealing groove. It is
NOTE 1—There is no equivalent ISO standard.
recommendedthatapotdiameterbetween31.75and44.45mm
[1.25 and 1.75 in.] be used whenever a choice is possible.
2. Referenced Documents
NOTE 2—Preliminary evidence indicates that, in many cases, reason-
2.1 ASTM Standards:
able correlations may be achieved between laboratories using presses with
D 883 Terminology Relating to Plastics
differentpotdiameters.Typicalexamplesarepresseswithpotdiametersof
D 958 Practice for Determining Temperatures of Standard
31.750, 38.100, and 44.450 mm [1.250, 1.500, and 1.750 in.]. However, a
ASTM Molds for Test Specimens of Plastics
few well-documented cases are recorded where differences in pot diam-
E 105 Practice for Probability Sampling of Materials
eters, even within this listed range, have caused large differences in
flow-length readings. Therefore, for best interlaboratory correlation it is
3. Terminology
recommended that identical pot diameters be used.
3.1 Definitions —Definitions in this test method are consis-
5.2 Standard Spiral-Flow Mold shown in Fig. 1 shall be
tent with Terminology D 883.
utilized.
4. Significance and Use
6. Materials
4.1 The spiral flow of a thermosetting molding compound is
6.1 Molding Compound:
a measure of the combined characteristics of fusion under
6.1.1 Any thermosetting molding compound with a spiral
pressure, melt viscosity, and gelation rate under specific
flow between 762 and 1270 mm [30 and 50 in.] as determined
conditions.
at the standard temperature and pressure of this test can be
evaluated.
This test method is under the jurisdiction ofASTM Committee D20 on Plastics
NOTE 3—Since the only commercially available molds are calibrated in
and is the direct responsibility of Subcommittee D20.30 on Thermal Properties
inches, spiral-flow length will be reported in these units. Conversion to SI
(Section D20.30.08).
units can readily be made by multiplying the flow length, in inches, by the
Current edition approved October 1, 2004. Published December 2004. Originally
appropriate conversion factor, 25.4 mm/in.
e1
approved in 1972. Last previous edition approved in 1999 as D 3123 - 98(99) .
2 NOTE 4—There is considerable evidence that the test is usable over a
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
wider range of flow lengths, but this has not yet been confirmed by
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
interlaboratory testing.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D3123–98 (2004)
FIG. 1 Standard Spiral-Flow Mold
6.1.2 Form—The form of the molding compound shall be nary moldings shall be made with the material to be tested to
loose powder or granules at 296 6 2 K (23 6 2°C [73.4 6 purge the helical runner before beginning the test. This
3.6°F]).
procedure is essential when changing from one compound to
another and is recommended as a routine practice.
NOTE 5—Preforms or pellets may be used if found necessary; however,
flow length may be affected by their use. 9.2 Molding Conditions:
9.2.1 Temperature—A temperature of 423 6 3 K (150 6
7. Sampling
3°C [302 6 5°F]) shall be maintained on the mold and transfer
7.1 Unless otherwise agreed upon between the seller and
plunger. The temperature may be measured in accordance with
purchaser, sampling shall be in accordance with Practice
the procedures described in Practice D 958 or by thermo-
E 105. Sampling, based on engineering principles, prior to
couples attached to the mold and plunger. The temperature
packaging shall be considered an acceptable alternative.
should be allowed to reach equilibrium by waiting at least 3
min between moldings.
8. Conditioning
...
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