Modular Supports System Product Technical Guide June 2026 | Page 203

Modular Support Systems Technical Guide, Edition 2
5.0 Reference
5.1 General Information for Load Tables
Galvanized Rigid Steel Conduit
The following tables are for information only. As per UL Standard Safety 6 manufactured to ANSI C80.1
For Galvanized Rigid Conduit( GRC) Trade Tolerances are for outer diameter:- /+ 0.015 inches for 1 / 2 " to 1-1 / 2”- /+ 1 % for 2” to 6”
Conduit weight is an approximation.
Trade Size in
1 / 2 3 / 4 1 1-1 / 4 1-1 / 2 2 2-1 / 2 3 3-1 / 2 4 5 6
Galvanized Rigid Conduit( GRC)
Avg Outer
Diameter in( mm)
Avg Inner
Diameter in( mm)
Avg Wall
Thickness tw in( mm)
Approximate
Weight lb / 100 ft
( kg / m)
0.84
0.632
0.104
82
( 21.3)
( 16.05)
( 2.64)
( 1.22)
1.05
0.836
0.107
109
( 26.7)
( 21.23)
( 2.72)
( 1.62)
1.315
1.063
0.126
161
( 33.4)
( 27.00)
( 3.20)
( 2.40)
1.66
1.394
0.133
218
( 42.2)
( 35.41)
( 3.38)
( 3.24)
1.99
1.624
0.138
263
( 50.5)
( 41.25)
( 3.51)
( 3.91)
2.375
2.083
0.146
350
( 60.3)
( 52.91)
( 3.71)
( 5.21)
2.875
2.489
0.193
559
( 73.0)
( 63.22)
( 4.90)
( 8.32)
3.5
3.09
0.205
727
( 88.9)
( 78.49)
( 5.21)
( 10.82)
4
3.57
0.215
880
( 101.6)
( 90.68)
( 5.46)
( 13.10)
4.5
4.05
0.225
1030
( 114.3)
( 102.87)
( 5.72)
( 15.33)
5.563
5.073
0.245
1520
( 141.3)
( 128.85)
( 6.22)
( 22.62)
6.625
6.093
0.266
1785
( 168.3)
( 154.76)
( 6.76)
( 26.56)
Rigid and Intermediate Metal Conduit shall be supported at least every 10 feet( 3.05 m) and within 3 feet( 914 mm) of each outlet box, junction box, cabinet, or fitting, except for straight runs of conduit connected with couplings which may be supported in accordance with NEC Article 345 and 346, provided such supports prevent transmission of stresses to termination where conduit is deflected between supports.
Intermediate Metal Conduit
The following tables are for information only. As per UL Standard Safety 6 manufactured to ANSI C80.1
For Intermediate Metal Conduit( IMC) Trade Tolerances are for outer diameter:- /+ 0.005 inches for 1 / 2” to 1”- /+ 0.0075 inches for 1-1 / 4” to 2”- /+ 0.10 inches for 2” to 4”
For Intermediate Metal Conduit( IMC) Trade Tolerances for wall thickness:- /+ 0.15 inches for 1 / 2” to 2”- /+ 0.20 inches for 2-1 / 2” to 4”
Conduit weight is an approximation.
Trade Size In
Intermediate Metal Conduit( IMC)
Avg Outer Diameter in( mm)
Avg Inner Diameter in( mm)
Avg Wall Thickness
tw in( mm)
Approximate Weight lb / 100 ft( kg / m)
1 / 2
0.815
( 20.70)
0.675
( 17.15)
0.07
( 1.8)
62
( 0.92)
3 / 4
1.029
( 26.14)
0.879
( 22.33)
0.075
( 1.9)
84
( 1.25)
1
1.29
( 32.77)
1.12
( 28.45)
0.085
( 2.2)
119
( 1.77)
1-1 / 4
1.638
( 41.61)
1.468
( 37.29)
0.085
( 2.2)
158
( 2.35)
1-1 / 2
1.883
( 47.83)
1.703
( 43.26)
0.09
( 2.3)
194
( 2.89)
2
2.36
( 59.94)
2.17
( 55.12)
0.095
( 2.4)
256
( 3.81)
2-1 / 2
2.857
( 72.57)
2.597
( 65.96)
0.14
( 3.6)
441
( 6.56)
3
3.476
( 88.29)
3.216
( 81.69)
0.14
( 3.6)
543
( 8.08)
3-1 / 2
3.971
( 100.86)
3.711
( 94.26)
0.14
( 3.6)
629
( 9.36)
4
4.466
( 113.44)
4.206
( 106.83)
0.14
( 3.6)
700
( 10.42)
Rigid and Intermediate Metal Conduit shall be supported at least every 10 feet( 3.05 m) and within 3 feet( 914 mm) of each outlet box, junction box, cabinet, or fitting, except for straight runs of conduit connected with couplings which may be supported in accordance with NEC Article 345 and 346, provided such supports prevent transmission of stresses to termination where conduit is deflected between supports.
202 Modular Support Systems Technical Guide Edition 2 | Installation Systems Hilti, Inc. 1-800-879-8000 | en español 1-800-879-5000 | www. hilti. com | Hilti( Canada) Corporation | 1-800-363-4458 | www. hilti. ca