MIL-DTL-87161F
4.3.4 Certification. For each contract or order, the wire rope manufacturer shall certify
specification. The certification shall include, as a minimum, actual results of the tests specified
herein and shall be retained on file at the manufacturer's facility for a minimum of 7 years.
4.4 Test methods.
4.4.1 Examination of product. Each sample of wire strand shall be visually examined for
workmanship and finish to determine compliance with 3.6.
4.4.1.1 Identification. Each wire strand shall be inspected for proper identification as
specified in 3.5.
4.4.2 Breaking strength. The wire strand specimen shall be selected from the sample
from each lot. The specimen may be gripped in the jaws of the testing machine or held in
suitable swaged or socketed terminals. In case of failure in grips or terminal, the test may be
disregarded and a new test conducted. The length of strand in the clear between grips or
terminals shall be no less than 10 inches (25 cm) or 10 strand lay lengths, whichever is larger.
The breaking strength shall be determined by use of a tensile testing machine in accordance with
applicable requirements of ASTM E 8. The breaking strength shall conform to the requirements
of table I for qualification and acceptance.
4.4.3 Stretch test. One specimen from each sample of wire strand selected as specified
in 4.3.2.3 shall be tested to determine the percent stretch. The total length of the wire strand
specimen to be tested shall not be less than 24 inches (60.9 cm). Where necessary, swaged
terminals and accompanying hardware may be used to facilitate installation of the specimen in
the jaws of the test machine. The amount of stretch shall be determined on a tension testing
machine in accordance with ASTM E 8. The specimen shall be loaded to one percent MBS
shown in table I to straighten the wire strand. While the specimen is under tension, an adequate
gauge length not less than 10 inches should be marked on the wire strand between the end
fittings of the testing specimen. The specimen shall then be loaded to 60 percent of MBS and
measured for elongation under load.
Elongation of gauge length under load
Percent stretch = -------------------------------------------------- x 100
Original gauge length
Results of the stretch test shall not exceed 1 percent change in length.
4.4.4 Test loading. The following test loading shall be made using the same wire strand
specimen used in the stretch test or similarly prepared specimen. Load the specimen to one
percent of breaking strength, then increase the loading to 85 percent of the minimum required
breaking strength of the wire strand specimen test, the wire strand fittings shall be removed and
the entire wire strand shall be completely unwound and every wire inspected. A suitable
acoustic, electronic device capable of detecting the breaking of individual wires during test
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