STANDARD HANDBOOK OF PETROLEUM & NATURAL GAS ...

Hoisting System 565
The purchaser may at his or her expense test all of the wires if the results of
the selected tests indicate that further checking is warranted.
Tensile Requirements of Individual Wire. Specimens shall not be less than
18 in. (457 mm) long, and the distance between the grips of the testing machine
shall not be less than 12 in. (305 mm). The speed of the movable head of the
testing machine, under no load, shall not exceed 1 in./min (0.4 mm/s). Any
specimen breaking within -$ in. (6.35 mm) from the jaws shall be disregarded
and a retest made.
Note: The diameter of wire can more easily and accurately be determined by placing
the wire specimen in the test machine and applying a load not over 25% of
the breaking strength of the wire.
The breaking strength of either bright (uncoated) or drawn-galvanized wires
of the various grades shall meet the values shown in Table 4-9 or Table 4-10
for the size wire being tested. Wire tested after rope fabrication allows one wire
in 6x7 classification, or three wires in 6x19 and 8x19 classifications and 18x7
and 19x7 constructions, or six wires in 6x37 classification or nine wires in 6x61
classification, or twelve wires in 6x91 classification wire rope to fall below, but
not more than 10% below, the tabular value for individual minimum. If, when
making the specified test, any wires fall below, but not more than 10% below,
the individual minimum, additional wires from the same rope shall be tested
until there is cause for rejection or until all of the wires in the rope have been
tested. Tests of individual wires in galvanized wire rope and of individual wires
in strand cores and in independent wire rope cores are not required.
Torsional Requirements of Individual Wire. The distance between the jaws
of the testing machine shall be 8 in. f in. (203 mm k 1 mm). For small
diameter wires, where the number of turns to cause failure is large, and in order
to save testing time, the distance between the jaws of the testing machine may
be less than 8 in. (203 mm). One end of the wire is to be rotated with respect
to the other end at a uniform speed not to exceed sixty 360" (6.28 rad) twists
per minute, until breakage occurs. The machine must be equipped with an
automatic counter to record the number of twists causing breakage. One jaw
shall be fixed axially and the other jaw movable axially and arranged for applying
tension weights to wire under test. Tests in which breakage occurs within .fi in.
(3.18 mm) of the jaw shall be discarded.
In the torsion test, the wires tested must meet the values for the respective
grades and sizes as covered by Table 4-12 or Table 4-13. In wire tested after
rope fabrication, it will be permissible for two wires in 6x7 classification or five
wires in 6x19 and 8x19 classifications and 18x7 and 19x7 constructions or ten wires
in 6x37 classification or fifteen wires in 6x61 classification, or twenty wires in
6x91 classification rope to fall below, but not more than 30% below, the specified
minimum number of twists for the individual wire being tested.
During the torsion test, tension weights as shown in Table 4-13 shall be
applied to the wire tested.
The minimum torsions for individual bright (uncoated) or drawn-galvanized
wire of the grades and sizes shown in Columns 7, 12, and 17 of Tables 4-9 and
410 shall be the number of 360' (6.28 rad) twists in an &in. (203 mm) length
that the wire must withstand before breakage occurs. Torsion tests of individual
wires in galvanized wire rope and of individual wires in strand cores and
independent wire rope cores are not required.
When the distance between the jaws of the testing machine is less than 8 in.
(203 mm), the minimum torsions shall be reduced in direct proportion to the
change in jaw spacing, or determined by