ASTM F1276-99(2009)
(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
Relations
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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 2009)
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.Anumber 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.
compressivestressbetweentwoplatens,withthestressapplied
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
calibrated bolt with a dial indicator. The bolt length is
1.3 The values stated in SI units are to be regarded as the
measured at the beginning of the test and at the end of the test.
standard. The values given in parentheses are for information
The percent relaxation is calculated from this.
only.
4. Significance and Use
1.4 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
4.1 This test method is designed to compare related mate-
responsibility of the user of this standard to establish appro-
rials under controlled conditions and their ability to maintain a
priate safety and health practices and determine the applica-
givencompressivestressasafunctionoftime.Aportionofthe
bility of regulatory limitations prior to use.
torque loss on the bolted flange is a result of creep relaxation.
Torque loss can also be caused by elongation of the bolts,
2. Referenced Documents
distortion of the flanges, and vibration; therefore, the results
2 obtained should be correlated with field results. This test
2.1 ASTM Standards:
method may be used as a routine test when agreed upon
A193/A193MSpecification for Alloy-Steel and Stainless
between the user and the producer.
Steel Bolting for High Temperature or High Pressure
Service and Other Special Purpose Applications
5. Apparatus
B637Specification for Precipitation-Hardening and Cold
5.1 Relaxometer, composed of two platens, special drilled
Worked Nickel Alloy Bars, Forgings, and Forging Stock
and calibrated bolt, washer and nut composed of Specification
for Moderate or High Temperature Service
A193/A193M Grade B7 or Specification B637 Grade UNS
E691Practice for Conducting an Interlaboratory Study to
N07718, or other alloys of construction that would satisfy the
Determine the Precision of a Test Method
calibration Procedure (see Annex) for the test temperature
F38TestMethodsforCreepRelaxationofaGasketMaterial
specified and a dial indicator assembly as shown in Fig. 1.
F104Classification System for Nonmetallic Gasket Materi-
als
5.2 Box End Wrench.
F868Classification for Laminated Composite Gasket Mate-
5.3 Steel Blanking Die.
rials
6. Test Specimens
6.1 Specimen size shall be 10.16 6 0.381 mm (0.400 6
This test method is under the jurisdiction ofASTM Committee F03 on Gaskets
0.015in.)wideby31.75 60.381mm(1.250 60.015in.)long.
and is the direct responsibility of Subcommittee F03.20 on Mechanical Test
Methods.
Current edition approved Oct. 1, 2009. Published March 2010. Originally
approved in 1990. Last previous edition approved in 2003 as F1276–99 (2003). Detailed working drawings of this apparatus are available from ASTM
DOI: 10.1520/F1276-99R09. Headquarters, 100 Barr Harbor Drive, West Conshohocken, PA 19428–2959 USA.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Order Adjunct No. 12-600-381-00.
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 (2009)
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±2°C(212±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 ± 2°C (212 ± 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 ± 2°C (212 ± 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 ± 2°C (212 ± 3.6°F)
millboard Cool as in Procedure A of
Classification F104
specified humidity, specimens shall be removed from the
chamber one at a time as needed.
7.3 Other conditioning may be as agreed upon between the
producer and the user.
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
FIG. 1 Relaxometer and Dial Indicator Assembly
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 Placethewasherinpositionandscrewonthenut,finger
6.2 Four specimens are required per test.
tight.
6.3 A minimum of three tests shall be conducted.
8.4 Screw on the dial indicator assembly, finger tight, and
6.4 Nominal thickness of specimens shall be that of the
set the dial indicator at the zero reading.
laminated composite gasket.
8.5 Applystresstothespecimensbytighteningthenutwith
a wrench until the desired dial indicator reading is reached;
7. Conditioning
record the reading (D ). Apply the stress in one continuous
o
7.1 When all nonmetallic layers of the laminated composite
motion with a maximum loading time of 3 s.Abolt elongation
are the same type, condition in accordance with that type as
of 0.1222 to 0.1270 mm (0.00481 to 0.00500 in.) is typical for
shown in Table 1.
a compressive force of 26.7 kN (6000 lbf). Remove the dial
indicator assembly. (The calibration procedure is outlined in
7.2 Whenthenonmetalliclayersofthelaminatedcomposite
Annex A1.)
are of different types, the specimen shall be conditioned for 22
h in a controlled-humidity room or in a closed chamber of air
NOTE 1—When testing materials thicker than 0.8 mm (0.03 in.), the
at21to30°C(70to85°F)and50to55%relativehumidity.In
time to tighten the nut may be extended to 5 s maximum to allow for the
all cases where testing is conducted outside the area of longer arc required to apply the test load.
F1276 − 99 (2009)
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 1—S=standard deviation, CV=% coefficient of variation=(S×100)⁄(average), LSD=% least significant difference between two individual
test results, and based on a 95% confidence level52 2 CV .
s d
œ
Repeatability Reproducibility
Relaxation
(Within Laboratories) (Between Laboratories)
Material Values,
% Average
SCV,% LSD,% SCV,% LSD,%
A 25.4 2.01 7.92 22.4 2.49 12.6 35.6
B 8.05 0.90 11.2 31.6 1.70 23.9
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.