STANDARD HANDBOOK OF PETROLEUM & NATURAL GAS ...

566 Drilling and Well Completions
Table 4-13
Applied Tension for Torsional Tests [12]
(1) (2) (3) (4)
Win Size
Minimum
Nominal Diameter
Applied Tension*
(in) (mm) Ob) (N)
0.011 to 0.016 0.28 to 0.42 1 4
0.017 to 0.020 0.43 to 0.52 2 9
0.021 to 0.030 053 to 0.77 4 18
0.031 to 0.040 0.78 to 1.02 6 27
8 36
0.041 to 0.050 1.03 to 1.28
0.051 to 0.060 1.29to 1.53 9 40
0.061 to 0.070 1.54 to 1.79
0.071 to 0.080 1.80 to 2.04
I1
13
49
58
0.081 to 0.090 2.05 to 2.30 16 71
0.091 to 0.100 to 231 2.55 19 85
0.101 to 0.1 10 256 to 2.80 21 93
0.1 1 I to0.120 2.81 to 3.06 23 IO2
0.121 too.130 3.07 to 3.3 1 25 111
'Weights shall not exceed twice the minimums listed.
(4-22)
where TS = minimum torsions for short wire
T, = minimum torsions for 8-in. (203-mm) length as given in Table 4-9
for size and grade of wire
Ls = distance between testing-machine jaws for short wire in in. (mm)
LL = 8 in. (203 mm)
Breaking Strength Requlrements for Wire Rope. The nominal strength of the
various grades of finished wire rope with fiber core shall be as specified in Tables
414, 415, and 416. The nominal strength of the various grades of wire rope having
a strand core or an independent wire-rope core shall be as specified in Tables 4-17
through 4-22. The nominal strength of the various types of flattened strand wire
rope shall be specified in Table 4-23. The nominal strength of the various grades
of drawn-galvanized wire rope shall be specified in Tables 4-14 through 423.
When testing finished wire-rope tensile test specimens to their breaking
strength, suitable sockets shall be attached by the correct method. The length
of test specimen shall not be less than 3 ft (0.91 m) between sockets for wire
ropes up to 1-in. (25.4 mm) diameter and not less than 5 ft (1.52 m) between
sockets for wire ropes 1 Q-in. (28.6 mm) to 3-in. (77 mm) diameter. On wire ropes
larger than 3 in. (77 mm), the clear length of the test specimen shall be at least
20 times the rope diameter. The test shall be valid if failure occurs 2 in. (50.8
mm) from the sockets or holding mechanism.
Due to the variables in sample preparation and testing procedures, it is
difficult to determine the true strength. Thus, the actual breaking strength
during test shall be at least 97.5% of the nominal strength as shown in the
applicable table. If the first specimen fails at a value below the 97.5% nominal
strength value, a second test shall be made, and if the second test meets the
strength requirements, the wire rope shall be accepted.