The Technology of Wire Wrapping

 

Wire Wrapping 101


A "Regular" bit wraps the bare wire around the terminal. A "Modofied" bit wraps a portion of insulation around the terminal in addition to the bare wire. This greatly increases the ability to withstand vibration.

A distinct advantage of wire wrapping is the ease with which a wire may be removed from a terminal to correct errors or modify wiring. An unwrap tool is slipped over the terminal, engaging the first turn of the connection. While rotating the tool, the connection is removed in seconds, without damage to the terminal

There is a constant surveillance of manufacturing dimensions. Each wrapping bit is subjected to a series of "Qualification Tests". These consist of wrapping groups of wire on various types of terminals. The wrapped wires are then subjected to a "strip" test to determine adequate tightness. "Unwrap" tests are also performed to ensure against an "Over Tight" wrap.

Solid wire is used for wire wrapped connections, and Copper is the most commonly used type. Minimum elongation of 15% is required for 24 through 32 AWG: 20% for larger wire.

 

Wire Size Chart

Bare Wire
Dia. (in)
Bare Wire
Dia. (mm)
AWG
(USA)
SWG
(GB)
.04031.02218-
.0401.016-19
.0360.9141920
.0320.8132021
.0280.7112122
.02530.64322-
.0240.61-23
.02260.57423-
.0220.559-24
.02010.5124-
.00200.508-25
.0180.457-26
.01790.45525-
.01640.417-27
.01590.40426-
.01480.376-28
.01420.36127-
.01360.345-29
.01260.32028-
.01240.315-30
.01160.295-31
.01130.28729-
.01080.274-32
.01000.2543033
.00920.234-34
.00890.22531-
.00840.213-35
.00080.20332-


 

Five Steps to Make A
Wire Wrap Connection


 

"Strip" Force Chart

Wire
AWG
Wire
Dia. (in)
Wire
Dia. (mm)
Min #
Turns
Bare Wire
Min Strip
Force (lbs.)
Min Strip
Force (g)
16.05101.304156800
18.04031.004156800
20.03200.80583600
22.02530.65583600
24.02010.50673200
26.01590.40762700
28.01260.32752200
30.01000.2573.31500


 

Terminal Diagonal Chart


In.
mm
.010
0.25
.015
0.38
.020
0.51
.025
0.64
.030
0.76
.035
0.89
.040
1.02
.045
1.14
.050
1.27
.055
1.40
.060
1.52
.065
1.65
.070
1.78
.075
1.91
.080
2.03
.085
2.16
.090
2.29
.095
2.41
.100
2.54
.010
0.25
.014
0.36
.018
0.46
.022
0.56
.027
0.69
.032
0.81
.036
0.91
.041
1.04
.046
1.17
.051
1.30
.056
1.42
.061
1.55
.066
1.68
.071
1.80
.076
1.93
.081
2.06
.086
2.18
.091
2.31
.096
2.44
.101
2.57
.015
0.38
.018
0.46
.021
0.53
.025
0.64
.029
0.74
.033
0.84
.038
0.97
.043
1.09
.047
1.19
.052
1.32
.057
1.45
.062
1.58
.067
1.70
.072
1.83
.077
1.96
.082
2.08
.087
2.21
.092
2.34
.097
2.46
.102
2.59
.020
0.51
.022
0.56
.025
0.64
.028
0.71
.032
0.81
.036
0.91
.040
1.02
.045
1.14
.049
1.25
.053
1.35
.058
1.47
.063
1.60
.068
1.73
.073
1.85
.078
1.98
.083
2.11
.088
2.24
.093
2.36
.098
2.49
.103
2.62
.025
0.64
.027
0.69
.029
0.74
.032
0.81
.035
0.89
.039
0.99
.043
1.09
.047
1.19
.050
1.27
.056
1.42
.060
1.52
.065
1.65
.069
1.75
.074
1.88
.079
2.01
.084
2.13
.089
2.26
.094
2.39
.099
2.52
.104
2.64
.030
0.76
.032
0.81
.033
0.84
.036
0.91
.039
0.99
.042
1.07
.046
1.17
.050
1.27
.054
1.37
.058
1.47
.062
1.58
.067
1.70
.071
1.80
.076
1.93
.080
2.03
.085
2.16
.090
2.29
.095
2.41
.100
2.54
.105
2.67
.035
0.89
.036
0.91
.038
0.97
.040
1.02
.043
1.09
.046
1.17
.049
1.25
.052
1.32
.056
1.42
.060
1.52
.064
1.63
.069
1.75
.073
1.85
.078
1.98
.082
2.08
.087
2.21
.091
2.31
.096
2.44
.101
2.57
.106
2.69
.040
1.02
.041
1.04
.043
1.09
.045
1.14
.047
1.19
.050
1.27
.052
1.32
.056
1.42
.060
1.52
.064
1.63
.068
1.73
.072
1.83
.076
1.93
.080
2.03
.084
2.13
.089
2.26
.092
2.34
.097
2.46
.102
2.59
.107
2.72
.045
1.14
.046
1.17
.047
1.19
.049
1.25
.050
1.27
.054
1.37
.056
1.42
.060
1.52
.063
1.60
.067
1.70
.071
1.80
.074
1.88
.078
1.98
.083
2.11
.087
2.21
.091
2.31
.096
2.44
.101
2.57
.105
2.67
.109
2.77
.050
1.27
.051
1.30
.052
1.31
.053
1.35
.056
1.42
.058
1.47
.060
1.52
.064
1.63
.067
1.70
.071
1.80
.074
1.88
.078
1.98
.082
2.08
.086
2.18
.090
2.29
.094
2.39
.098
2.49
.103
2.62
.107
2.72
.111
2.82