ASTM F1588-96

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
An American National Standard
Designation: F 1588 – 96
Standard Test Method for
Constant Tensile Load Joint Test (CTLJT)
This standard is issued under the fixed designation F 1588; 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 OPS Part 192, Title 49
1.1 The constant tensile load joint test (CTLJT) is designed
3. Terminology
to demonstrate that a joint in a plastic piping system is resistant
3.1 Definitions:
to the effects of long-term creep.
3.1.1 General—Definitions are in accordance with Test
1.1.1 The joint is subjected to an internal pressure at least
Method D 638 and Terminology F 412, unless otherwise speci-
equal to its operating pressure and a sustained axial tensile load
fied. Abbreviations are in accordance with Terminology
for a specified time period, usually 1000 h. The joint shall not
D 1600.
leak, nor may the pipe completely pull out for the test duration.
3.1.2 The gas industry terminology used in this test method
The total axial stress is set by the referencing document.
is in accordance with the definitions given in ANSI B31.8 or
1.1.2 Some typical conditions for testing of joints on poly-
OPS Part 192, Title 49, unless otherwise indicated.
ethylene pipe are described in Appendix X1.
3.2 Definitions of Terms Specific to This Standard:
1.2 This test is usually performed at 73°F (22.8°C).
3.2.1 mechanical joint, Category 1—a mechanical joint
1.3 The CTLJT was developed to demonstrate the long-term
design that provides a seal plus a resistance to force on the pipe
resistance to pullout of mechanical joints on polyethylene gas
end, equal to or greater than that which will cause a permanent
pipe. The CTLJT has also been successfully applied to the
deformation of the pipe or tubing. (D 2513)
evaluation of other components of plastic piping systems.
3.2.2 mechanical joint, Category 3—a mechanical joint
These applications are discussed in Appendix X1.
design that provides a seal plus a pipe restraint rating equiva-
1.4 This standard does not purport to address all of the
lent to the anticipated thermal stresses occurring in a pipeline.
safety concerns, if any, associated with its use. It is the
This category has a manufacturers’ pipe-end restraint that
responsibility of the user of this standard to establish appro-
allows slippage at less than the value required to yield the pipe.
priate safety and health practices and determine the applica-
(D 2513)
bility of regulatory limitations prior to use.
3.2.3 pipe—refers to both pipe and tubing.
2. Referenced Documents
4. Summary of Test Method
2.1 ASTM Standards:
4.1 A joint is subjected to a sustained axial load for a
D 638 Test Method for Tensile Properties of Plastics
specified period of time (usually 1000 h). The test duration and
D 1600 Terminology for Abbreviated Terms Relating to
the actual test conditions (axial stress, internal pressure, test
Plastics
duration, and test temperature) are either specified by a
D 2122 Test Method for Determining Dimensions of Ther-
3 referencing document or, for new or unique applications,
moplastic Pipe and Fittings
agreed upon between the user and the manufacturer. X1.2
D 2513 Specification for Thermoplastic Gas Pressure Pipe,
3 contains a background discussion of axial stress values and
Tubing, and Fittings
3 axial load determination.
F 412 Terminology Relating to Plastic Piping Systems
4.2 The joint is made to plastic pipe of the type, grade, size,
2.2 ANSI Standard:
4 and dimension ratio to be used in the final application. The
B31.8 Gas Transmission and Distribution Piping Systems
axial tensile stress should be as high as possible, but shall be
2.3 Code of Federal Regulations:
lower than the stress at which the plastic material continues to
stretch and finally yields (the long-term yield strength) (see
This test method is under the jurisdiction of ASTM Committee F-17 on Plastic
Note 1).
Piping Systems and is the direct responsibility of Subcommittee F17.40 on Test
Methods.
NOTE 1—During the first hours of a test, the pipe elongates measurably.
Current edition approved March 10, 1996. Published May 1996. Originally
Elongation continues for the duration of the test at a decaying rate.
published as F 1588 – 95. Last previous edition F 1588 – 95.
Annual Book of ASTM Standards, Vol 08.01.
Annual Book of ASTM Standards, Vol 08.04.
4 5
Available from the American National Standards Institute, 11 W. 42nd St., 13th Available from Superintendent of Documents, Government Printing Office,
Floor, New York, NY 10036. Washington, DC 20402.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
F 1588
4.3 A joint passes this test if it does not leak and does not gage shall be able to measure the test pressure to within an
pull out or allow slippage in excess of the manufacturers’ accuracy of 1 % or better.
specified design slippage during the test duration. 6.4 Test Assembly:
4.4 If a pipe in the test assembly yields before the specified 6.4.1 The test assembly is capped and verified to be leak
minimum test time is attained, the total stress is above the tight. Attachment devices that ensure straight line axial loading
long-term yield strength of that pipe and the test shall be shall be used at each end to attach the test assembly to the
performed again at a stress level calculated to be below the loading device. The test assembly may contain more than one
long-term yield strength of the pipe. joint of the size under evaluation (see Note 3).
5. Significance and Use NOTE 3—There are many configurations possible with the wide variety
of joints that are available. If the mechanical joint to be tested is suitable
5.1 This test method was designed to be used to validate the
for the purpose, it can be used to cap the pipe ends.
long-term resistance to pullout of joints designed for use in
6.4.2 The minimum length is three pipe diameters between
plastic natural gas piping systems.
fittings (stiffener ends). Elongation is proportional to specimen
5.2 This test method is used in addition to the short-term
length. It is important to allow sufficient space in the apparatus
tests required by OPS Part 192.283b, Title 49. Informal
to provide for anticipated elongation of the test specimen for
versions of this test method are used by manufacturers and
the duration of the test.
utilities to demonstrate that a joint is resistant to the effects of
long-term creep and meets the requirements for classification
7. Precautions and Safety Considerations
as a Category 1 or a Category 3 joint in accordance with
Specification D 2513. 7.1 Each test fixture and joint assembly shall be designed to
5.3 This test method may also be applicable for the deter- safely accommodate a sudden unexpected failure in any part of
mination of the effects of a sustained axial load on joints or the test assembly. Both fixture and joint(s) shall be regularly
other components of plastic piping systems designed for other inspected for safety. Joint pullouts usually occur unexpectedly
applications. Test parameters and the internal pressurizing and proceed from start to finish in seconds. Failure may be
fluid, if any, should be listed in the referencing document. accompanied by the sudden release of the internal pressure or
5.4 Documents that reference this test method for products a falling test assembly, or both.
other than joints shall specify test conditions and performance 7.2 It is strongly recommended that water be used as the
requirements. In general, such products pass this test if they pressurizing fluid when testing systems that may fail in a brittle
manner (specifically PVC systems). If that is not possible, the
maintain their structural integrity, do not leak, and perform to
specification during and after the test. test specimens shall be placed in a strong chamber at all times
when pressurized (see Note 4).
6. Apparatus
NOTE 4—For example, after 938 h of uneventful testing, one 6-in. IPS
6.1 Loading Methods:
transition joint rapidly pulled apart. There was no indication of pipe
6.1.1 Any loading method that maintains the correct, in-line
movement when inspected 5 min before failure.
tensile load on the joint (within 62 %) for the test duration is
acceptable. Loading methods successfully employed for all
8. Test Specimens
size loads include lever arms, hydraulic cylinders, and air
8.1 Pipe Specimen Selection:
cylinders.
8.1.1 For tests of fittings intended for use in natural gas
6.1.2 Dead weight (a pile of scrap steel or iron) has worked
distribution systems, the pipe supply used for the tests shall
well for loads up to 1 ton (907 kg) (see Note 2).
have a print line signifying that it was manufactured to the
NOTE 2—To provide an adequate stress level for ⁄8 in. DR 7 PE tubing, requirements of Specification D 2513.
about 200 lb (90 kg) are required. Pipe 2 in. SDR11 PE requires about
8.1.2 Pipe specimens used for fittings tests shall meet the
2000 lb (907 kg).
dimensional requirements of the referencing document. (See
Note 5.) The dimensions of the pipe specimens selected for use
6.1.3 Hydraulic and air-powered loading frames have been
constructed to provide up to 50 000 lb (22 680 kg) for tests on in an evaluation shall be known and reported.
3-in. IPS through 8-in. IPS joints. The stroke of the cylinder
NOTE 5—Some fittings may perform well with pipe of the nominal
should be adequate for the material being tested.
outside diameter and wall thickness and fail if assembled to pipe at the
6.2 Applied Axial Load Determination Monitoring—T
...