Standard Test Method for Compressive Strength of Gaskets at Elevated Temperatures

SIGNIFICANCE AND USE
The compressive strength or crush-extrusion resistance of a gasket material is a major factor with regard to the selection of a given material for use in a particular sealing application. The significance of the test method is based, in part, on the assumption that a material, once it has been crushed or extruded, will no longer function as effectively as a seal. This assumption can only be used as a guide, however, since exact yield or failure points are difficult to define for gasket materials (which are usually viscoelastic in nature). Two or more materials can be compared to determine differences in their resistance to compressive stress. A sample of material can be compared to an established standard or previously determined characteristics on original lots of the same material, for quality assurance purposes. See 6.2 for discussion of specimen area and geometry effects.
SCOPE
1.1 This test method covers the determination of compressive strength characteristics (crush-extrusion resistance) of gasket materials at elevated temperature.
1.2 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.
1.3 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.

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Publication Date
30-Sep-2003
Technical Committee
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ASTM F1574-03a - Standard Test Method for Compressive Strength of Gaskets at Elevated Temperatures
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:F1574–03a
Standard Test Method for
Compressive Strength of Gaskets at Elevated
1
Temperatures
This standard is issued under the fixed designation F1574; 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 4. Significance and Use
4.1 The compressive strength or crush-extrusion resistance
1.1 This test method covers the determination of compres-
sive strength characteristics (crush-extrusion resistance) of of a gasket material is a major factor with regard to the
gasket materials at elevated temperature. selection of a given material for use in a particular sealing
1.2 The values stated in SI units are to be regarded as the application. The significance of the test method is based, in
standard. The values in parentheses are for information only. part, on the assumption that a material, once it has been
1.3 This standard does not purport to address all of the crushed or extruded, will no longer function as effectively as a
safety concerns, if any, associated with its use. It is the seal. This assumption can only be used as a guide, however,
responsibility of the user of this standard to establish appro- since exact yield or failure points are difficult to define for
priate safety and health practices and determine the applica- gasketmaterials(whichareusuallyviscoelasticinnature).Two
bility of regulatory limitations prior to use. or more materials can be compared to determine differences in
their resistance to compressive stress.Asample of material can
2. Referenced Documents
be compared to an established standard or previously deter-
2
2.1 ASTM Standards: mined characteristics on original lots of the same material, for
F104 Classification System for Nonmetallic Gasket Mate-
quality assurance purposes. See 6.2 for discussion of specimen
rials area and geometry effects.
F1315 Test Method for Density of a Sheet Gasket Material
5. Apparatus
3
3. Summary of the Test Method
5.1 Testing Machine , for applying a known value of com-
3.1 Specimens cut from gasket material are subjected to
pressive stresses to specimens. The machine should be capable
various stresses perpendicular to the flat surface of the speci- of applying a stress of up to 520 MPa (75 400 psi) (tolerance
mens for a specified time at 150°C (302°F). Dimensional of 65 %), depending on the indent resistance of the steel
changes to the thickness and in the plane of the specimen are
platens and the means of reading the applied load.
determined while it is under stress and after the stress has been 5.2 HardenedSteelPlatens,Two (Rockwell of C35 to 40 or
removed. A graphical display of percent deformation plotted
equivalent), circular shape, larger than the specimen diameter.
against the applied stress will enable determination of a A suitable size is a diameter of approximately 100 mm (3.94
compressive yield stress point beyond which the material will
in.). The surface finish shall be RMS 0.25 to 0.50 µm (10 to 20
no longer decrease in thickness without also extruding in the µm). Fig. 1 shows a suitable arrangement of steel platens and
planar dimensions. This condition is also revealed by physical
test specimen.
measurements of the change in size of the specimens in the 5.3 Device for Applying Heat to Platens sufficient to
planardimensions.Testsmaybeperformedatvarioustempera-
achieve a desired temperature at interface with gasket material
tures, as agreed upon between the producer and the user, to specimens. An example of this device is also shown in Fig. 1,
determine the relationship between temperature and compres-
where a resistance heater surrounds the hardened platens. In
sive behavior. some cases, the loading device itself may be heated, such as
with a hot press. Any appropriate means is acceptable. The
recommended elevated temperature is 150 6 5°C (302 6 9°F).
1
This test method is under the jurisdiction ofASTM Committee F03 on Gaskets
Other temperatures may be employed as desired, or as agreed
and is the direct responsibility of Subcommittee F03.20 on Mechanical Test
Methods.
upon between the producer and the user.
Current edition approved Oct. 1, 2003. Published October 2003. Originally
approved in 1995. Last previous edition approved in 2003 as F1574 – 03. DOI:
10.1520/F1574-03A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Examples of such equipment include Baldwin-Southwark, Instron, Tinius-
Standards volume information, refer to the standard’s Document Summary page on Olsen, MTS, or any type of pressing device which has b
...

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