Hazardous Conditions

Particularly hazardous conditions including offshore activities, the lifting of persons and lifting of potentially dangerous loads such as molten metals, corrosive materials or fissile materials. In such cases the degree of hazard should be assessed by a competent person and the working load limit adjusted accordingly.

Steel Wire Rope Slings

General

General: Steel wire rope slings are in most cases easier and less expensive than chain slings. Galvanised wire rope provides good protection against corrosion, in extreme environments stainless wire ropes can be used. For extremely heavy lifting wire rope slings are usually the best option.
Material/Design: For manufacturing of wire rope slings the rope grade shall be either 1770 or 1960 N/mm². In multi-leg slings the rope dimension and grade shall be the same for each leg. The working load limit of the lower terminal fitting(s) shall be at least equal to that of the leg(s) to which it is/they are fitted. Where a terminal fitting is used, the eye termination shall always be fitted with a thimble. For 3- and 4-leg slings a master link with intermediate link should bee used.
Safety factor: 5:1.

Ferrule/Splicing

The minimum length of plain rope between the inside ends of ferrules terminating a sling leg shall be 20 times the nominal rope diameter. The minimum length of plain rope between the tails of splices shall be at least 15 times the nominal rope diameter. For endless sling the length between the ferrules shall not be less than three times the length of the ferrule after pressing.

Soft Eye

The peripheral length (l) of a soft eye shall be at least four rope lay lengths. CERTEX Svenska apply as standard that the length (h) of the soft eye shall be at least 15 times the rope diameter.

Multi Leg Slings

The working load limit of any master link shall be at least equal to that of the sling. The working load limit of any intermediate link fitted to a three-leg or four-leg sling shall be at least equal to 1,6 times the WLL of one of the legs suspended from it.

WARNING! When using the steel wire rope sling for projected lifting with an angel (ß) less then 45o, the working load limit will increase. This shall be informed by the time of order.

Length

Length
The length (L) shall be that measured between the bearing points of the sling or the circumference length of an endless sling.

Single leg and endless slings
The measured length of a ferrule-secured sling shall not differ from the nominal length by more than two rope diameters or 1 % of the nominal length, whichever is the greater.

The measured length of a spliced sling shall not differ from the nominal length by more than four rope diameters or 2 % of the nominal length, whichever is the greater.

Where single leg slings are intended to be used as matched sets, the difference in length of matched sets of ferrule-secured eye slings shall not exceed the rope diameter, or 0,5 % of the nominal length, whichever is the greater.

Multi leg slings
The measured individual leg length of a ferrule-secured sling shall not differ from the nominal length of the sling by more than two rope diameters or 1 % of the nominal length, whichever is the greater.

The difference in length between the individual legs of any multi-leg sling under no load shall not exceed 1,5 times the rope diameter or 0,5 % of the nominal length, whichever is the greater.

"Laid" (cable-laid) endless slings
The measured length for cable-laid grommets with diameter <61 mm the tolerance shall be ±1d or 1% of the nominal length, whichever is the greater. For cable-laid grommets with diameter >65mm the tolerance shall be ±0,5d or 0,5% of the nominal length, whichever is the greater.

Marking

Each sling shall be provided with a marking plate or be marked in the ferrules (single leg and endless slings) with the manufacturer's identifying mark, working load limit (WLL), length, manufacturing date and CE marking.

Wire Rope Fittings

P-ferrules, cylindrical ferrules: Straight edges against the wire rope. Externally diameter is approximately two times the rope diameter. Total length is approximately 4,5 times the rope diameter.

PK-ferrules, cylindrical/conical ferrules: Cone against the wire rope in one end, the other end is straight. Externally diameter is approximately two times the rope diameter. Total length is approximately 5-6 times the rope diameter.

R-ferrules, cylindrical end stop: Straight edges against the wire rope. Externally diameter is approximately two times the rope diameter. Total length is approximately 4,5 times the rope diameter.

T-LOC, steel reinforcement turnback ferrule: For rotation resistant wire rope when used together with solid thimble. Prevents the aluminum ferrule from splitting. Swaged together with a standard turnback ferrule. Approved for wire ropes of grade 2160 N/mm2.

Material: Aluminum alloy/steel alternatively copper alloy/stainless steel for stainless steel rope slings.

Socketing
Socketing achieves with zinc alloy, pure zinc or with cold tempered two-component compound in our standard sockets or in special sockets according to customers desires.

Splice
Splicing achieves as a short splice, crane splice, long splice or grommets.

Swaged terminals
Swaging of terminals achieves by roller pressing the terminal over single wire rope. Standard terminals are available in stainless material, but are also manufactured in other materials and constructions according to the customers desires.

Wire Rope Fittings

The most commonly used rope fittings with indication of remaining percentage of steel wire min breaking force.

Dimensioning for Steel Wire Rope Slings

Working load limit (WLL) for steel wire rope sling

Single leg sling
WLL (ton) = (Fmin x KT) / (Zp x g)

Endless sling (choke)
WLL (ton) = (Fmin x KT x 2 x 0,8) / (Zp x g)

Multi-leg sling
WLL (ton) = (Fmin x KT x KL) / (Zp x g)


Fmin = the minimum breaking force of the rope, in kN.
KT = factor for the efficiency of the termination, for ferrule 0,9 and for spliced 0,8.
KL = the leg factor relating to the number of legs and the angle to the vertical, see WLL-table.
Zp = the coefficient of utilization (working coefficient), with the value 5.
g = 9,81

Bending diameters effect on the working load limit (WLL)
CERTEX recommend that consideration will be taken to that the slings capacity will be lower when the bending diameter decreasing. If, for example the rope bends around a bearing point witch have the same diameter as the rope itself the capacity will decrease to the half, see figure.

Working Load Limit (WLL)

Fibre core

General: Working load limits for slings with fibre core in grade 1770 or 1960 N/mm2  ferrule-secured, P- or PK-ferrules.

Fibre core - 1770 N/mm²

Rope
WLL in tons for steel wire rope with fibre core 1770 N/mm²
 
 
 
 
 
 
 
 
 
Ø
Single
 
 
2-leg & basket*
 
3- 4-leg*
 
Endless
 
 
 

 

 

 

 

 

 

 

 

 

 

mm

Straight

Choked

Basket

0°-45°
45°-60°
0°-45°
45°-60°

Straight

Choked

Basket

3
0,09
0,07
0,18
0,12
0,09
0,19
0,13
0,18
0,14
0,36
4
0,15
0,12
0,3
0,21
0,15
0,31
0,22
0,3
0,24
0,6
5
0,25
0,2
0,5
0,35
0,25
0,5
0,35
0,5
0,4
1
6
0,35
0,28
0,7
0,5
0,35
0,7
0,5
0,7
0,55
1,4
7
0,5
0,4
1
0,7
0,5
1
0,75
1
0,8
2
8
0,7
0,55
1,4
0,95
0,7
1,5
1,05
1,4
1,1
2,8
9
0,85
0,7
1,7
1,2
0,85
1,8
1,3
1,7
1,4
3,4
10
1,05
0,85
2,1
1,5
1,05
2,25
1,6
2,1
1,7
4,2
11
1,3
1
2,6
1,8
1,3
2,7
1,95
2,6
2,12
5,2
12
1,55
1,2
3,1
2,12
1,55
3,3
2,3
3,1
2,5
6,2
13
1,8
1,4
3,6
2,5
1,8
3,85
2,7
3,6
2,9
7,2
14
2,12

1,7

4,2
3
2,12
4,35
3,15
4,24
3,3
8,48
16
2,7
2,2
5,4
3,85
2,7
5,65
4,2
5,4
4,35
10,8
18
3,4
2,7
6,8
4,8
3,4
7,2
5,2
6,8
5,65
13,6
20
4,35
3,4
8,7
6
4,35
9
6,5
8,7
6,9
17,4
22
5,2
4,1
10,4
7,2
5,2
11
7,8
10,4
8,4
20,8
24
6,3
5
12,6
8,8
6,3
13,5
9,4
12,6
10
25,2
26
7,2
5,8
14,4
10
7,2
15
11
14,4
11,8
28,8
28
8,4
6,7
16,8
11,8
8,4
18
12,5
16,8
13,5
33,6
32
11
8,8
22
15
11
23,5
16,5
22
18
44
36
14
11,2
28
19
14
29
21
28
22,5
56
40
17
13,6
34
23,5
17
36
26
34
28
68
44
21
16,8
42
29
21
44
31,5
42
33,5
84
48
25
20
50
35
25
52
37
50
40
100
52
29
23,2
58
40
29
62
44
58
47
116
56
33,5
26,8
67
47
33,5
71
50
67
54
134
60
39

31,2

78
54
39
81
58
78
63
156
Factor (KL)
1
0,8
2
1,4
1
2,1
1,5
2
1,6
4
* When using a multi-leg sling in a choker hitch - reduce the value with 20%.
 
 
 
 
 
 
 
 
 
 

Fibre core - 1960 N/mm²

Rope
WLL in tons for steel wire rope with fibre core 1960 N/mm²
 
 
 
 
 
 
 
 
 
Ø
Single
 
 
2-leg & basket*
 
3- 4-leg*
 
Endless
 
 

mm

Straight

Choked

Basket

0°-45°
45°-60°
0°-45°
45°-60°

Straight

Choked

Basket

3
0,1
0,08
0,2
0,14
0,1
0,21
0,15
0,2
0,18
0,4
4
0,18
0,14
0,38
0,25
0,18
0,38
0,27
0,36
0,3
0,72
5
0,28
0,22
0,56
0,38
0,28
0,57
0,4
0,56
0,43
1,12
6
0,4
0,32
0,8
0,56
0,4
0,84
0,6
0,8
0,64
1,6
7
0,55
0,4
1,1
0,75
0,55
1,1
0,83
1,1
0,9
2,2
8
0,75
0,6
1,5
1,1
0,75
1,6
1,1
1,4
1,2
3
9
0,9
0,8
1,8
1,26
0,9
2
1,4
1,8
1,5
3,6
10
1,2
0,95
2,4
1,7
1,2
2,5
1,8
2,4
1,9
4,8
11
1,4
1,1
2,8
2
1,4
3
2,2
2,8
2,3
5,6
12
1,7
1,3
3,4
2,4
1,7
3,6
2,6
3,4
2,7
6,8
13
2
1,6
4
2,8
2
4,2
3
4
3,2
8
14
2,3

1,8

4,6
3,2
2,3
4,8
3,5
4,6
3,7
9,2
16
3
2,4
6
4,2
3
6,3
4,5
6
4,8
12
18
3,8
3,1
7,6
5,3
3,8
8
5,7
7,6
6,1
15,2
20
4,7
3,8
9,4
6,6
4,7
10
7,1
9,4
7,6
18,8
22
5,7
4,6
11,4
8
5,7
12
8,5
11,4
9,2
23
24
6,8
5,4
13,6
9,5
6,8
14,3
10,2
13,6
11
27
26
8
6,4
16
11,2
8
16,8
12
16
12,8
32
28
9,3
7,4
18,6
13
9,3
19,5
14
18,6
15
37
32
12
9,7
24
16,8
12
25,5
18
24
19,5
48
36
15
12
30
21
15
32
23
30
25
60
40
19
15
38
27
19
40
28,5
38
30
76
44
23
18
46
32
23
48
34
46
37
92
48
27
22
54
38
27
57
41
54
44
108
52
32
26
64
45
32
67
48
64
51
128
56
37
30
74
52
37
78
56
74
60
148
60
43

34

86
60
43
90
64
86
68
172
68
55
44
110
77
55
115
82
110
88
220
71
60
48
120
84
60
126
90
120
96
240
Factor (KL)
1
0,8
2
1,4
1
2,1
1,5
2
1,6
4
* When using a multi-leg sling in a choker hitch - reduce the value with 20%.
 
 
 
 
 
 
 
 
 
 

Steel core

General: Working load limits for slings with steel core in grade 1770 N/mm2 and 1960 N/mm2 ferrule-secured, P- or PK-ferrules.

Steel core - 1770 N/mm²

Rope
WLL in tons for wire rope with steel core 1770 N/mm²
 
 
 
 
 
 
 
 
 
Ø
Single
 
 
2-leg & Basket*
 
3-4-leg*
 
Endless
 
 

mm 

Straight

Choked

Basket

0°-45°
45°-60°
0°-45°
45°-60°

Straight

Choked

Basket

3
0,1
0,08
0,2
0,14
0,1
0,21
0,15
0,2
0,16
0,4
4
0,17
0,14
0,34
0,24
0,17
0,36
0,25
0,34
0,27
0,68
5
0,27
0,22
0,54
0,38
0,27
0,56
0,41
0,54
0,43
1,08
6
0,38
0,3
0,76
0,53
0,38
0,8
0,57
0,76
0,61
1,52
7
0,53
0,42
1,06
0,74
0,53
1,1
0,8
1,06
0,85
2,12
8
0,75
0,6
1,5
1,05
0,75
1,55
1,1
1,5
1,2
3
9
0,95
0,75
1,9
1,3
0,95
2
1,4
1,9
1,5
3,8
10
1,15
0,9
2,3
1,6
1,15
2,4
1,7
2,3
1,85
4,6
11
1,4
1,1
2,8
2
1,4
3
2,12
2,8
2,25
5,6
12
1,7
1,35
3,4
2,3
1,7
3,55
2,5
3,4
2,7
6,8
13
2
1,6
4
2,8
2
4,15
3
4
3,15
8
14
2,25

1,8

4,5
3,15
2,25
4,8
3,4
4,5
3,7
9
16
3
2,4
6
4,2
3
6,3
4,5
6
4,8
12
18
3,7
3
7,4
5,2
3,7
7,8
5,65
7,4
6
14,8
20
4,6
3,7
9,2
6,5
4,6
9,8
6,9
9,2
7,35
18,4
22
5,65
4,5
11,3
7,8
5,65
11,8
8,4
11,3
9
22,6
24
6,7
5,4
13,4
9,4
6,7
14
10
13,4
10,6
26,8
26
7,8
6,2
15,6
11
7,8
16,5
11,5
15,6
12,5
31,2
28
9
7,2
18
12,5
9
19
13,5
18
14,5
36
32
11,8
9,4
23,6
16,5
11,8
25
17,5
23,6
19
47,2
36
15
12
30
21
15
31,5
22,5
30
23,5
60
40
18,5
14,8
37
26
18,5
39
28
37
30
74
44
22,5
18
45
31,5
22,5
47
33,5
45
36
90
48
26
20,8
52
37
26
55
40
52
42
104
52
31,5
25,2
63
44
31,5
66
47
63
50
126
56
36
28,8
72
50
36
76
54
72
58
144
60
42

33,6

84
58
42
88
63
84
67
168
Factor (KL)
1
0,8
2
1,4
1
2,1
1,5
2
1,6
4
* When using a multi-leg sling in a choker hitch - reduce the value with 20%.
 
 
 
 
 
 
 
 
 
 

Steel core - 1960 N/mm²

Rope
WLL in tons for wire rope with steel core 1960 N/mm²
 
 
 
 
 
 
 
 
 
Ø
Single
 
 
2-leg & Basket*
 
3-4-leg*
 
Endless
 
 

mm 

Straight

Choked

Basket

0°-45°
45°-60°
0°-45°
45°-60°

Straight

Choked

Basket

3
0,11
0,09
0,22
0,15
0,11
0,23
0,16
0,22
0,17
0,44
4
0,19
0,15
0,38
0,27
0,19
0,4
0,28
0,38
0,3
0,76
5
0,3
0,24
0,6
0,42
0,3
0,63
0,45
0,6
0,5
1,2
6
0,43
0,34
0,86
0,6
0,43
0,9
0,65
0,86
0,7
1,7
7
0,6
0,5
1,2
0,8
0,6
1,2
0,88
1,2
0,9
2,3
8
0,8
0,65
1,6
1,15
0,8
1,7
1,2
1,6
1,3
3,2
9
1,05
0,8
2,1
1,45
1,05
2,2
1,8
2,1
1,7
4,2
10
1,3
1
2,6
1,8
1,3
2,7
1,9
2,6
2
5,2
11
1,5
1,2
3
2,2
1,5
3,3
2,3
3
2,5
6
12
1,8
1,4
3,6
2,6
1,8
3,9
2,8
3,6
3
7,2
13
2,2
1,8
4,4
3
2,2
4,5
3,2
4,4
3,5
8,8
14
2,5

5
3,5
2,5
5,3
3,8
5
4
10
16
3,3
2,6
6,6
4,6
3,3
6,9
4,9
6,6
5,2
13,2
18
4,1
3,3
8,2
5,8
4,1
8,7
6,2
8,2
6,6
16,4
20
5,1
4,1
10,2
7,2
5,1
10,7
7,7
10,2
8,2
20,4
22
6,2
5
12,4
8,7
6,2
13
9,3
12,4
10
24,8
24
7,4
5,9
14,8
10,3
7,4
15,5
11,1
14,8
11,8
29,6
26
8,7
7
17,4
12,1
8,7
18,2
13
17,4
13,8
34,8
28
10
8
20
14
10
21
15
20
16
40
32
13
10,4
26
18,4
13
27,5
19,7
26
21
52
36
16,6
13,3
33
23
16,6
35
25
33
26,5
66
40
20,5
16,4
41
29
20,5
43
31
41
33
82
44
25
20
50
35
25
52
37
50
40
100
48
29,5
23,6
59
41
29,5
62
44
59
47
118
52
35
28
70
48
35
73
52
70
55
140
56
40
32
80
56
40
84
60
80
64
160
60
46

37 

92
65
46
97
69
92
74
184
Factor (KL)
1
0,8
2
1,4
1
2,1
1,5
2
1,6
4
* When using a multi-leg sling in a choker hitch - reduce the value with 20%.
 
 
 
 
 
 
 
 
 
 

Temperature Affect on Working Load Limit (WLL)

Temperature affect on working load limit (WLL)

Account should be taken of the maximum temperature that can be reached by the wire rope sling in service. This is difficult in practice but underestimation of the temperature should be avoided.
The table below summarises the necessary de-rated working load limits of a sling due to temperature, taking into account the type of rope termination, the ferrule material and the core of the rope.

When wire rope slings are to be used in temperatures below -40 °C CERTEX should be consulted.

The use of wire rope slings within the permissible temperature ranges given in the table does not require any
permanent reduction in working load limit when the rope is returned to ambient temperature.

Termination

Ferrule-
Rope
De-rated working load limit expressed as % of WLL of the sling
 
 
 
 
 
type
material
core
Temperature (t) ºC
 
 
 
 
 
 
 
 
-40 - 100
101 - 150
151 - 200
201 - 300
301 - 400
400<t
Ferrule
Aluminium
Fibre
100
Do not use
Do not use
Do not use
Do not use
Do not use
Ferrule
Aluminium
Steel
100
100
Do not use
Do not use
Do not use
Do not use
Ferrule
Steel
Fibre
100
Do not use
Do not use
Do not use
Do not use
Do not use
Ferrule
Steel
Steel
100
100
90
75
65
Do not use
Splice
-
Fibre
100
Do not use
Do not use
Do not use
Do not use
Do not use
Splice
-
Steel
100
100
90
75
65
Do not use
Socket
zinc/alloy
Fibre
-40 - 80ºC 100%
 
 
 
 
 
Socket
zinc/alloy
Steel
-40 - 120ºC 100%
 
 
 
 
 
Socket
2-component
Fibre
-50 - 80ºC 100%
 
 
 
 
 
Socket
2-component
Steel
-50 - 80ºC 100%
 
 
 
 
 

Acidic conditions

Wire rope slings should not be used either immersed in acidic solutions or exposed to acid fumes.

Chemical affect

CERTEX should be consulted in case the slings are to be exposed to chemicals combined with high temperature.