ASTM D3419-12

Standard Practice for In-Line Screw-Injection Molding Test Specimens From Thermosetting Compounds

SIGNIFICANCE AND USE
This practice is subject to the definition of injection molding given in 3.1.2 with the further provision that with in-line screw injection the plastic compound, heated in a chamber by conduction and friction, is fluxed by the action of a reciprocating screw and then is forced into a hot mold where it solidifies. Hereafter, in-line screw-injection molding will be referred to simply as injection molding.
The mold referenced in this section (see Fig. 1) is generally useful, and describes what have been the most common specimens required for the testing of thermosets. ISO specimens and testing are gaining favor, however. Practice D3641 and ISO 10724 describe the layout and practice for injection molding the multi-purpose specimens in accordance with ISO 3167.
Typically, injection-molded test specimens are made with shorter cycles than those used for similar moldings made by compression, and the cycle is equal to or faster than that for transfer molding.
Breathing of the mold is not usually required to release trapped volatile material as the gas is free to flow from the vent end of the mold. This is particularly advantageous for heat-resistant compounds and reduces the tendency for molded specimens to blister at high exposure temperatures.
Injection molding is intended for low-viscosity compounds. One set of processing parameters cannot be specified for all types of thermosetting materials, nor for samples of the same material having different plasticities.
Materials containing fibrous fillers such as glass roving, chopped cloth, or cellulosic fibers can be injection molded, but their properties will be affected depending upon how much fiber breakdown occurs as the compound is worked by the screw and as it passes through the system of runners and gates. The orientation of the fibers in the molded specimen will also affect injection-molded properties.
Flow and knit lines in a molded piece are often sites of mechanical or electrical weakness. The fluxed mater...
SCOPE
1.1 This practice covers the general principles to be followed when injection molding test specimens of thermosetting materials. It is to be used to obtain uniformity in methods of describing the various steps of the injection molding process and in the reporting of those conditions. The exact molding conditions will vary from material to material, and if not incorporated in the material specification, shall be agreed upon between the purchaser and the supplier or determined by previous experience with the particular type of material being used and its plasticity.
Note 1—The utility of this practice has been demonstrated for the molding of thermosetting molding compounds exhibiting lower-viscosity non-Newtonian flow.  
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.
1.3 This standard does not purport to address all of the safety problems, 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.
1.4 This practice assumes the use of reciprocating screw injection molding machines.
Note 2—This standard and ISO 10724 address the same subject matter, but differ in technical content.

General Information

• Status: Historical
• Publication Date: 31-Mar-2012
• ICS: 83.140.99 - Other rubber and plastics products
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.09 - Specimen Preparation

Relations

• Replaces: ASTM D3419-00(2006) - Standard Practice for In-Line Screw-Injection Molding Test Specimens From Thermosetting Compounds
• Effective Date: 01-Apr-2012
• Replaced By: ASTM D3419-12(2019) - Standard Practice for In-Line Screw-Injection Molding Test Specimens From Thermosetting Compounds
• Effective Date: 01-May-2019
• Referred By: ASTM D5948-05(2020) - Standard Specification for Molding Compounds, Thermosetting
• Effective Date: 01-Apr-2012
• Referred By: ASTM D6289-13(2019) - Standard Test Method for Measuring Shrinkage from Mold Dimensions of Molded Thermosetting Plastics
• Effective Date: 01-Apr-2012

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D3419 − 12
Standard Practice for
In-Line Screw-Injection Molding Test Specimens From
1
Thermosetting Compounds
This standard is issued under the fixed designation D3419; 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 (´) indicates an editorial change since the last revision or reapproval.
3
1. Scope* 2.2 ISO Standards:
ISO 10724 :1994(E)—Plastics—Thermosetting Moulding
1.1 This practice covers the general principles to be fol-
Materials—Injection Moulding of Multipurpose Test
lowed when injection molding test specimens of thermosetting
Specimens
materials. It is to be used to obtain uniformity in methods of
ISO 3167 :1993, Plastics—Multipurpose Test Specimens
describing the various steps of the injection molding process
and in the reporting of those conditions. The exact molding
3. Terminology
conditions will vary from material to material, and if not
3.1 Definitions:
incorporated in the material specification, shall be agreed upon
3.1.1 General—Definitions of terms applying to this prac-
between the purchaser and the supplier or determined by
tice appear in Terminology D883.
previous experience with the particular type of material being
used and its plasticity.
3.1.2 injection molding—the process of forming a material
by forcing it, in a fluid state and under pressure, through a
NOTE 1—The utility of this practice has been demonstrated for the
runner system (sprue, runner, and gate(s)) into the cavity of a
molding of thermosetting molding compounds exhibiting lower-viscosity
non-Newtonian flow. closed mold.
3.1.2.1 Discussion—Screw-injection molding and reaction-
1.2 The values stated in SI units are to be regarded as
injection molding are types of injection molding.
standard. The values given in parentheses are for information
only. 3.2 Definitions of Terms Specific to This Standard:
3.2.1 breathing, v—theoperationofopeningamoldorpress
1.3 This standard does not purport to address all of the
for a very short period of time at an early stage in the process
safety problems, if any, associated with its use. It is the
of cure.
responsibility of the user of this standard to establish appro-
3.2.1.1 Discussion—Breathing allows the escape of gas or
priate safety and health practices and determine the applica-
vapor from the molding material and reduces the tendency of
bility of regulatory limitations prior to use.
thick moldings to blister.
1.4 This practice assumes the use of reciprocating screw
injection molding machines.
3.2.2 cavity (of a mold), n—the space within a mold to be
filled to form the molded product.
NOTE 2—This standard and ISO 10724 address the same subject matter,
but differ in technical content.
3.2.3 landing (of a cavity), v—the practice of relieving the
mold around the cavity (cavities), thus reducing the surface
2. Referenced Documents
area of the flat mating surfaces of the mold halves.
3
2
3.2.3.1 Discussion—Typical lands are 4.5 mm ( ⁄16 in.) to 6
2.1 ASTM Standards:
1
mm ( ⁄4 in.) in width. It is recommended that landing pads be
D883 Terminology Relating to Plastics
incorporated to hold the mold open 0.0125 mm (0.0005 in.) to
D3641 Practice for Injection Molding Test Specimens of
prevent damage to the lands.
Thermoplastic Molding and Extrusion Materials
4. Significance and Use
1 4.1 This practice is subject to the definition of injection
This practice is under the jurisdiction ofASTM Committee D20 on Plastics and
is the direct responsibility of Subcommittee D20.09 on Specimen Preparation. molding given in 3.1.2 with the further provision that with
Current edition approved April 1, 2012. Published May 2012. Originally
in-line screw injection the plastic compound, heated in a
approved in 1975. Last previous edition approved in 2006 as D3419 - 00(2006).
chamber by conduction and friction, is fluxed by the action of
DOI: 10.1520/D3419-12.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
*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
1

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D3419 − 12
a reciprocating screw and then is forced into a hot mold where 4.6 Materials containing fibrous fillers such as glass roving,
it solidifies. Hereafter, in-line screw-injection molding will be chopped c
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:D3419–00 (Reapproved 2006) Designation: D3419 – 12
Standard Practice for
In-Line Screw-Injection Molding Test Specimens From
1
Thermosetting Compounds
This standard is issued under the fixed designation D3419; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1This practice covers the general principles to be followed when injection molding test specimens of thermosetting materials.
It is to be used to obtain uniformity in methods of describing the various steps of the injection molding process and in the reporting
of those conditions. The exact molding conditions will vary from material to material, and should become part of the material
specification or be agreed upon between the purchaser and the supplier. *
1.1 Thispracticecoversthegeneralprinciplestobefollowedwheninjectionmoldingtestspecimensofthermosettingmaterials.
It is to be used to obtain uniformity in methods of describing the various steps of the injection molding process and in the reporting
of those conditions. The exact molding conditions will vary from material to material, and if not incorporated in the material
specification,shallbeagreeduponbetweenthepurchaserandthesupplierordeterminedbypreviousexperiencewiththeparticular
type of material being used and its plasticity.
NOTE 1—The utility of this practice has been demonstrated for the molding of thermosetting molding compounds exhibiting lower-viscosity
non-Newtonian flow.
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.
1.3 This standard does not purport to address all of the safety problems, 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.
1.4 This practice assumes the use of reciprocating screw injection molding machines.
NOTE2—This standard is similar in content (but not technically equivalent) to ISO 10724: 1994(E). 2—This standard and ISO 10724 address the same
subject matter, but differ in technical content.
2. Referenced Documents
2
2.1 ASTM Standards:
D883 Terminology Relating to Plastics
D958Practice for Determining Temperatures of Standard ASTM Molds for Test Specimens of Plastics 3641 Practice for
Injection Molding Test Specimens of Thermoplastic Molding and Extrusion Materials
3
2.2 ISO Standards:
ISO 10724:10724 :1994(E)—Plastics—Thermosetting Moulding Materials—Injection Moulding of Multipurpose Test Speci-
mens
ISO 3167:1993, Plastics—Multipurpose Test Specimens ISO 3167 :1993, Plastics—Multipurpose Test Specimens
3. Terminology
3.1 Definitions:
3.1.1 General—Definitions of terms applying to this practice appear in Terminology D883.
3.1.2 injection molding—the process of forming a material by forcing it, in a fluid state and under pressure, through a runner
system (sprue, runner, and gate(s)) into the cavity of a closed mold.
3.1.3Discussion
1
This practice is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.09 on Specimen Preparation.
Current edition approved March 15, 2006. Published March 2006. Originally approved in 1975. Last previous edition approved in 2000 as D3419-00. DOI:
10.1520/D3419-00R06.
Current edition approved April 1, 2012. Published May 2012. Originally approved in 1975. Last previous edition approved in 2006 as D3419 - 00(2006). DOI:
10.1520/D3419-12.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
*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.
1

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D3419 – 12
3.1.2.1 Discussion—Screw-injection molding and reaction-injection molding are types of injection molding.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 breathing, v—the operation of opening
...