General Order 64-A
Appendix
B
Mechanical And Loading Data For Conductors
The tables included in these appendices contain mechanical data of copper wire, copper covered wire, steel wire, iron wire and cable most commonly used in electrical supply and communication lines; also, the maximum wire loadings for light and heavy loading districts as outlined in Section IV.
In the compiling of the curves in Appendix C the values of the tables herein, together with the following data, have been used:
Modulus of Elasticity:
| Copper covered steel, solid |
20,000,000 lbs. per sq. in. |
| Copper covered steel, stranded |
17,000,000 lbs. per sq. in. |
| Copper |
16,800,000 lbs. per sq. in. |
| Steel, solid |
29,000,000 lbs. per sq. in. |
| Steel, stranded |
21,000,000 lbs. per sq. in. |
| Iron, drawn |
26,000,000 lbs. per sq. in. |
Coefficient of Linear Thermal Expansion:
| Copper covered steel |
0.72 x 10-5 per degree F. |
| Copper |
0.96 x 10-5 per degree F. |
| Steel |
0.67x 10-5 per degree F. |
The breaking load of stranded conductors has been taken as 90 percent of the sum of the breaking loads of individual strands.
TABLES
No. 14 – Hard Drawn Copper Wire – Solid – Bare.
No. 15 – Hard Drawn Copper Wire – Solid – Bare.
No. 16 – Hard Drawn Copper Wire – Stranded – Bare.
No. 17 – Soft Drawn Copper Wire – Solid – Weatherproof.
No. 18 – Soft Drawn Copper Wire – Stranded – Weatherproof.
No. 19 – Hard Drawn Copper Covered Wire – Solid – Bare.
No. 20 – Steel Wire – Solid Bare, Roebling (St. W.G.).
No. 21 – Steel and Iron Wire – Solid – Bare, Birmingham (B.W.G.)
No. 22 – Galvanized Steel Strands.