ASTM F1276-99(2003)
(Test Method)Standard Test Method for Creep Relaxation of Laminated Composite Gasket Materials
Standard Test Method for Creep Relaxation of Laminated Composite Gasket Materials
SIGNIFICANCE AND USE
This test method is designed to compare related materials under controlled conditions and their ability to maintain a given compressive stress as a function of time. A portion of the torque loss on the bolted flange is a result of creep relaxation. Torque loss can also be caused by elongation of the bolts, distortion of the flanges, and vibration; therefore, the results obtained should be correlated with field results. This test method may be used as a routine test when agreed upon between the user and the producer.
SCOPE
1.1 This test method provides a means of measuring the amount of creep relaxation of a laminated composite gasket material at a predetermined time after a compressive stress has been applied.
1.2 Creep relaxation is measured by means of a calibrated bolt with dial indicator.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.4 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.
General Information
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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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:F1276–99 (Reapproved 2003)
Standard Test Method for
Creep Relaxation of Laminated Composite Gasket Materials
This standard is issued under the fixed designation F1276; 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 2.2 ASTM Adjuncts:
Relaxometer, Method B (Adjunct to Test Method F38)
1.1 This test method provides a means of measuring the
amount of creep relaxation of a laminated composite gasket
3. Summary of Test Method
material at a predetermined time after a compressive stress has
3.1 In this test method, the specimen is subjected to a
been applied.
compressive stress between two platens, with the stress applied
1.2 Creep relaxation is measured by means of a calibrated
by a nut and bolt. Run at room or elevated temperatures, the
bolt with dial indicator.
stress is determined by measuring the change in length of the
1.3 The values stated in SI units are to be regarded as the
calibrated bolt with a dial indicator. The bolt length is
standard. The values given in parentheses are for information
measured at the beginning of the test and at the end of the test.
only.
The percent relaxation is calculated from this.
1.4 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
4. Significance and Use
responsibility of the user of this standard to establish appro-
4.1 This test method is designed to compare related mate-
priate safety and health practices and determine the applica-
rials under controlled conditions and their ability to maintain a
bility of regulatory limitations prior to use.
given compressive stress as a function of time.Aportion of the
2. Referenced Documents torque loss on the bolted flange is a result of creep relaxation.
2 Torque loss can also be caused by elongation of the bolts,
2.1 ASTM Standards:
distortion of the flanges, and vibration; therefore, the results
A193/A193M Specification for Alloy-Steel and Stainless
obtained should be correlated with field results. This test
Steel Bolting Materials for High Temperature or High
method may be used as a routine test when agreed upon
Pressure Service and Other Special Purpose Applications
between the user and the producer.
B637 Specification for Precipitation-Hardening Nickel Al-
loy Bars, Forgings, and Forging Stock for High-
5. Apparatus
Temperature Service
5.1 Relaxometer, composed of two platens, special drilled
E691 Practice for Conducting an Interlaboratory Study to
and calibrated bolt, washer and nut composed of Specification
Determine the Precision of a Test Method
A193/A193M Grade B7 or Grade UNS N07718, or other
F38 Test Methods for Creep Relaxation of a Gasket Mate-
alloys of construction that would satisfy the calibration Proce-
rial
dure (see Annex) for the test temperature specified and a dial
F104 Classification System for Nonmetallic Gasket Mate-
indicator assembly as shown in Fig. 1.
rials
5.2 Box End Wrench.
F868 Classification for Laminated Composite Gasket Ma-
5.3 Steel Blanking Die.
terials
6. Test Specimens
This test method is under the jurisdiction ofASTM Committee F03 on Gaskets
6.1 Specimen size shall be 10.16 6 0.381 mm (0.400 6
and is the direct responsibility of Subcommittee F03.20 on Mechanical Test
0.015in.)wideby31.75 60.381mm(1.250 60.015in.)long.
Methods.
6.2 Four specimens are required per test.
Current edition approved Oct. 1, 2003. Published October 2003. Originally
approved in 1990. Last previous edition approved in 1999 as F1276 – 99. DOI:
6.3 A minimum of three tests shall be conducted.
10.1520/F1276-99R03.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Dario P. Bernasconi, 40 Farrington St., Stoughton, MA 02072, and Donald G.
Standards volume information, refer to the standard’s Document Summary page on Johnson, Metal Samples, P.O. Box 8, Munford, AL 36268, are suppliers of the
the ASTM website. relaxometer.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
F1276–99 (2003)
TABLE 1 Test Method for Creep Relaxation of Laminated
Composite Materials Conditioning for Laminated Composite
Gasket Materials
Classification
F104
Type of Gasket Identification
Conditioning
Material in the First Two
Procedure
Nonmetallic Layers Numerals
of Six-Digit
Number
Compressed asbestos sheet; F11, F12, 1hat100 6 2°C (212 6 3.6°F)
asbestos beater sheet; F51, F52 Cool in desiccator over
flexible graphite anhydrous calcium chloride
21 to 30°C (70 to 85°F)
Asbestos paper and millboard F13 4 h at 100 6 2°C (212 6 3.6°F)
Cool as in Procedure A of
Classification F104
Cork composition F21, F23 At least 46 h at 21 to 30°C
Cork and cellular rubber (70 to 85°F) and 50 to 55 %
relative humidity
Cork and rubber F22 At least 46 h at 21 to 30°C
(70 to 85°F) and 50 to 55 %
relative humidity
Treated and untreated papers F31, F32, 4 h at 21 to 30°C (70 to 85°F)
from cellulose or other F33, F34 over anhydrous calcium
organic fibers chloride followed immediately
by at least 20 h at 21 to 30°C
(70 to 85°F) and 50 to 55 %
relative humidity
Compressed nonasbestos F71, F72 1 h at 100 6 2°C (212 6 3.6°F)
sheet; nonasbestos beater Cool in desiccator over
sheet anhydrous calcium chloride
21 to 30°C (70 to 85°F)
Nonasbestos paper and F73 4 h at 100 6 2°C (212 6 3.6°F)
millboard Cool as in Procedure A of
Classification F104
8. Procedure
8.1 Clean all surfaces and lightly lubricate the washer and
bolt threads; graphite and molybdenum disulfide have been
found to be acceptable lubricants.
8.2 Place the specimens between the platens in accordance
with Fig. 1 making sure they are no closer than 2 mm (0.078
in) to the other pieces and the edge of the platens.
8.3 Place the washer in position and screw on the nut, finger
tight.
8.4 Screw on the dial indicator assembly, finger tight, and
FIG. 1 Relaxometer and Dial Indicator Assembly
set the dial indicator at the zero reading.
8.5 Apply stress to the specimens by tightening the nut with
a wrench until the desired dial indicator reading is reached;
6.4 Nominal thickness of specimens shall be that of the
record the reading (D ). Apply the stress in one continuous
o
laminated composite gasket.
motion with a maximum loading time of 3 s.Abolt elongation
of 0.1222 to 0.1270 mm (0.00481 to 0.00500 in.) is typical for
7. Conditioning
a compressive force of 26.7 kN (6000 lbf). Remove the dial
7.1 When all nonmetallic layers of the laminated composite
indicator assembly. (The calibration procedure is outlined in
are the same type, condition in accordance with that type as
Annex A1.)
shown in Table 1.
7.2 When the nonmetallic layers of the laminated composite NOTE 1—When testing materials thicker than 0.8 mm (0.03 in.), the
time to tighten the nut may be extended to 5 s maximum to allow for the
are of different types, the specimen shall be conditioned for 22
longer arc required to apply the test load.
h in a controlled-humidity room or in a closed chamber of air
at 21 to 30°C (70 to 85°F) and 50 to 55 % relative humidity. In 8.6 Place the specimen unit in a hot air-circulating oven for
all cases where testing is conducted outside the area of 22hat100 6 2°C (212 6 3.6°F), unless otherwise specified.
specified humidity, specimens shall be removed from the The maximum test temperature for SpecificationA193/A193M
chamber one at a time as needed. Grade B7 shall not exceed 204°C (400°F). The maximum test
7.3 Other conditioning may be as agreed upon between the temperature for Grade UNS N07718 shall not exceed 482°C
producer and the user. (900°F).
F1276–99 (2003)
TABLE 2 Precision and Bias Data
FORMAT A Precision of Creep Relaxation Test of Laminated Composite Gasket Materials Using Coefficient of Variation
Method of Presenting Results on a Percentage Basis
NOTE—S = standard deviation, CV = % coefficient of variation = (S 3 100)/(average), LSD = % least significant difference between two individual test
results, and b
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