| Structural members | Light duty (Up to 25 pounds per square foot)—Height in feet | Heavy duty (25 to 75 pounds per square foot)—Height in feet | ||||
|---|---|---|---|---|---|---|
| ≤24 | >24≤40 | >40≤60 | ≤24 | >24≤40 | >40≤60 | |
| Poles or uprights (in inches) | 2 x 4 | 3 x 4 or 2 x 6 | 4 x 4 | 3 x 4 | 4 x 4 | 4 x 6 |
| Bearers (in inches) | 2 x 6 | 2 x 6 | 2 x 6 | 2 x 8 | 2 x 8 | 2 x 10 |
| Ledgers (in inches) | 2 x 6 | 2 x 6 | 2 x 6 | 2 x 8 | 2 x 8 | 2 x 8 |
| Stringers (not supporting bearers) (in inches) | 1 x 6 | 1 x 6 | 1 x 6 | 1 x 6 | 1 x 6 | 1 x 6 |
| Braces (in inches) | 1 x 4 | 1 x 6 | 1 x 6 | 1 x 6 | 1 x 6 | 1 x 6 |
| Pole spacing—longitudinally (in feet) | 71/2 | 71/2 | 71/2 | 7 | 7 | 7 |
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| Pole spacing—transversely (in feet) | 61/2 min | 71/2 min | 81/2 min | 61/2 | 10 | 10 |
| Ledger spacing—vertically (in feet) | 7 | 7 | 7 | 41/2 | 41/2 | 41/2 |
| Length (in feet) | Cross section (in inches) | |
|---|---|---|
| At ends | At center | |
| 15 | 17/8 x 23/4 | 17/8 x 33/4 |
| 16 | 17/8 x 23/4 | 17/8 x 33/4 |
| 18 | 17/8 x 3 | 17/8 x 4 |
| 20 | 17/8 x 3 | 17/8 x 4 |
| 24 | 17/8 x 3 | 17/8 x 41/2 |
| Structural members | Height in feet | ||
|---|---|---|---|
| ≤10 | >10≤16 | 16≤20 | |
| inches | inches | inches | |
| Legs | 2 x 4 | 3 x 4 | 4 x 6 |
| Bearers or headers | 2 x 6 | 2 x 8 | 4 x 6 |
| Crossbraces | 2 x 4 | 2 x 4 | 2 x 6 |
| or | |||
| 1 x 8 | |||
| Longitudinal braces | 2 x 4 | 2 x 6 | 2 x 6 |
| Span in feet | Lumber dimensions in inches | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| A | B | A | B | A | B | A | B | A | B | |
| 2 x 10 | 15/8 x 91/2 | 2 x 12 | 15/8 x 111/2 | 3 x 8 | 25/8 x 71/2 | 3 x 10 | 25/8 x 91/2 | 3 x 12 | 25/8 x 111/2 | |
| 6 | 256 | 309 | 526 | 667 | 807 | |||||
| 8 | 192 | 232 | 395 | 500 | 605 | |||||
| 10 | 153 | 186 | 316 | 400 | 484 | |||||
| 12 | 128 | 155 | 263 | 333 | 404 | |||||
| 14 | 110 | 133 | 225 | 286 | 346 | |||||
| 16 | 116 | 197 | 250 | 303 | ||||||
| (A)—Rough lumber. | ||||||||||
| (B)—Dressed lumber. | ||||||||||
| [In pounds or tons of 2,000 pounds] | |||||
| Circumferences | Diameter in inches | Single leg | 60° bridle | 45° bridle | 30° bridle |
|---|---|---|---|---|---|
| lbs. | lbs. | lbs. | lbs. | ||
| 3/4 | 1/4 | 120 | 204 | 170 | 120 |
| 1 | 5/16 | 200 | 346 | 282 | 200 |
| 11/8 | 3/8 | 270 | 467 | 380 | 270 |
| 11/4 | 7/16 | 350 | 605 | 493 | 350 |
| 13/8 | 15/32 | 450 | 775 | 635 | 450 |
| 11/2 | 1/2 | 530 | 915 | 798 | 530 |
| 13/4 | 9/16 | 690 | 1190 | 973 | 690 |
| 2 | 5/8 | 880 | 1520 | 1240 | 880 |
| 21/4 | 3/4 | 1080 | 1870 | 1520 | 1080 |
| 21/2 | 13/16 | 1300 | 2250 | 1830 | 1300 |
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| 23/4 | 7/8 | 1540 | 2660 | 2170 | 1540 |
| 3 | 1 | 1800 | 3120 | 2540 | 1800 |
| Tons | Tons | Tons | Tons | ||
| 31/4 | 11/16 | 1.0 | 1.7 | 1.4 | 1.0 |
| 31/2 | 11/8 | 1.2 | 2.1 | 1.7 | 1.2 |
| 33/4 | 11/4 | 1.35 | 2.3 | 1.9 | 1.35 |
| 4 | 15/16 | 1.5 | 2.6 | 2.1 | 1.5 |
| 41/2 | 11/2 | 1.8 | 3.1 | 2.5 | 1.8 |
| 5 | 15/8 | 2.25 | 3.9 | 3.2 | 2.25 |
| 51/2 | 13/4 | 2.6 | 4.5 | 3.7 | 2.6 |
| 6 | 2 | 3.1 | 5.4 | 4.4 | 3.1 |
| 61/2 | 21/8 | 3.6 | 6.2 | 5.1 | 3.6 |
| [In tons of 2,000 pounds] | |||||||||
| Rope diameter | Single leg | Vertical | A | B | C | Choker | A | B | C |
|---|---|---|---|---|---|---|---|---|---|
| 6×19 Classification | |||||||||
| 1/4″ | .59 | .56 | .53 | .44 | .42 | .40 | |||
| 3/8″ | 1.3 | 1.2 | 1.1 | .98 | .93 | .86 | |||
| 1/2″ | 2.3 | 2.2 | 2.0 | 1.7 | 1.6 | 1.5 | |||
| 5/8″ | 3.6 | 3.4 | 3.0 | 2.7 | 2.5 | 2.2 | |||
| 3/4″ | 5.1 | 4.9 | 4.2 | 3.8 | 3.6 | 3.1 | |||
| 7/8″ | 6.9 | 6.6 | 5.5 | 5.2 | 4.9 | 4.1 | |||
| 1″ | 9.0 | 8.5 | 7.2 | 6.7 | 6.4 | 5.4 | |||
| 11/8″ | 11 | 10 | 9.0 | 8.5 | 7.8 | 6.8 | |||
| 6×37 Classification | |||||||||
| 11/4″ | 13 | 12 | 10 | 9.9 | 9.2 | 7.9 | |||
| 13/8″ | 16 | 15 | 13 | 12 | 11 | 9.6 | |||
| 11/2″ | 19 | 17 | 15 | 14 | 13 | 11 | |||
| 13/4″ | 26 | 24 | 20 | 19 | 18 | 15 | |||
| 2″ | 33 | 30 | 26 | 25 | 23 | 20 | |||
| 21/4″ | 41 | 38 | 33 | 31 | 29 | 25 | |||
| (A)—Socket or Swaged Terminal attachment. | |||||||||
| (B)—Mechanical Sleeve attachment. | |||||||||
| (C)—Hand Tucked Splice attachment. | |||||||||
| [in tons of 2,000 pounds] | |||||||||||||||||
| Two-leg bridle or basket hitch | Rope diameter | Vertical | A | B | C | 60° bridle | A | B | C | 45° bridle | A | B | C | 30° bridle | A | B | C |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 6×19 Classification | |||||||||||||||||
| 1/4″ | 1.2 | 1.1 | 1.0 | 1.0 | .97 | .92 | .83 | .79 | .75 | .59 | .56 | .53 | |||||
| 3/8″ | 2.6 | 2.5 | 2.3 | 2.3 | 2.1 | 2.0 | 1.8 | 1.8 | 1.6 | 1.3 | 1.2 | 1.1 | |||||
| 1/2″ | 4.6 | 4.4 | 3.9 | 4.0 | 3.8 | 3.4 | 3.2 | 3.1 | 2.8 | 2.3 | 2.2 | 2.0 | |||||
| 5/8″ | 7.2 | 6.8 | 6.0 | 6.2 | 5.9 | 5.2 | 5.1 | 4.8 | 4.2 | 3.6 | 3.4 | 3.0 | |||||
| 3/4″ | 10 | 9.7 | 8.4 | 8.9 | 8.4 | 7.3 | 7.2 | 6.9 | 5.9 | 5.1 | 4.9 | 4.2 | |||||
| 7/8″ | 14 | 13 | 11 | 12 | 11 | 9.6 | 9.8 | 9.3 | 7.8 | 6.9 | 6.6 | 5.5 | |||||
| 1″ | 18 | 17 | 14 | 15 | 15 | 12 | 13 | 12 | 10 | 9.0 | 8.5 | 7.2 | |||||
| 11/8″ | 23 | 21 | 18 | 19 | 18 | 16 | 16 | 15 | 13 | 11 | 10 | 9.0 | |||||
| 6×37 Classification | |||||||||||||||||
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| 11/4″ | 26 | 24 | 21 | 23 | 21 | 18 | 19 | 17 | 15 | 13 | 12 | 10 | |||||
| 13/8″ | 32 | 29 | 25 | 28 | 25 | 22 | 22 | 21 | 18 | 16 | 15 | 13 | |||||
| 11/2″ | 38 | 35 | 30 | 33 | 30 | 26 | 27 | 25 | 21 | 19 | 17 | 15 | |||||
| 13/4″ | 51 | 47 | 41 | 44 | 41 | 35 | 36 | 33 | 29 | 26 | 24 | 20 | |||||
| 2″ | 66 | 61 | 53 | 57 | 53 | 46 | 47 | 43 | 37 | 33 | 30 | 26 | |||||
| 21/4″ | 83 | 76 | 66 | 72 | 66 | 57 | 58 | 54 | 47 | 41 | 38 | 33 | |||||
| (A)—Socket or Swaged Terminal Attachment. | |||||||||||||||||
| (B)—Mechanical Sleeve Attachment. | |||||||||||||||||
| (C)—Hand Tucked Splice Attachment. | |||||||||||||||||
| [in tons of 2,000 pounds] | |||||||||
| Rope diameter | Single leg | Vertical | A | B | C | Choker | A | B | C |
|---|---|---|---|---|---|---|---|---|---|
| 6×19 Classification | |||||||||
| 1/4″ | .55 | .51 | .49 | .41 | .38 | .37 | |||
| 3/8″ | 1.2 | 1.1 | 1.1 | .91 | .85 | .80 | |||
| 1/2″ | 2.1 | 2.0 | 1.8 | 1.6 | 1.5 | 1.4 | |||
| 5/8″ | 3.3 | 3.1 | 2.8 | 2.5 | 2.3 | 2.1 | |||
| 3/4″ | 4.8 | 4.4 | 3.9 | 3.6 | 3.3 | 2.9 | |||
| 7/8″ | 6.4 | 5.9 | 5.1 | 4.8 | 4.5 | 3.9 | |||
| 1″ | 8.4 | 7.7 | 6.7 | 6.3 | 5.8 | 5.0 | |||
| 11/8″ | 10 | 9.5 | 8.4 | 7.9 | 7.1 | 6.3 | |||
| 6×37 Classification | |||||||||
| 11/4″ | 12 | 11 | 9.8 | 9.2 | 8.3 | 7.4 | |||
| 13/8″ | 15 | 13 | 12 | 11 | 10 | 8.9 | |||
| 11/2″ | 17 | 16 | 14 | 13 | 12 | 10 | |||
| 13/4″ | 24 | 21 | 19 | 18 | 16 | 14 | |||
| 2″ | 31 | 28 | 25 | 23 | 21 | 18 | |||
| (A)—Socket or Swaged Terminal attachment. | |||||||||
| (B)—Mechanical Sleeve attachment. | |||||||||
| (C)—Hand Tucked Splice attachment. | |||||||||
| [In tons of 2,000 pounds] | |||||||||||||||||
| Two-leg bridle or basket hitch | Rope diameter | Vertical | A | B | C | 60° bridle | A | B | C | 45° bridle | A | B | C | 30° bridle | A | B | C |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 6 × 19 Classification | |||||||||||||||||
| 1/4″ | 1.1 | 1.0 | .99 | .95 | .88 | .85 | .77 | .72 | .70 | .55 | .51 | .49 | |||||
| 3/8″ | 2.4 | 2.2 | 2.1 | 2.1 | 1.9 | 1.8 | 1.7 | 1.6 | 1.5 | 1.2 | 1.1 | 1.1 | |||||
| 1/2″ | 4.3 | 3.9 | 3.7 | 3.7 | 3.4 | 3.2 | 3.0 | 2.8 | 2.6 | 2.1 | 2.0 | 1.8 | |||||
| 5/8″ | 6.7 | 6.2 | 5.6 | 5.8 | 5.3 | 4.8 | 4.7 | 4.4 | 4.0 | 3.3 | 3.1 | 2.8 | |||||
| 3/4″ | 9.5 | 8.8 | 7.8 | 8.2 | 7.6 | 6.8 | 6.7 | 6.2 | 5.5 | 4.8 | 4.4 | 3.9 | |||||
| 7/8″ | 13 | 12 | 10 | 11 | 10 | 8.9 | 9.1 | 8.4 | 7.3 | 6.4 | 5.9 | 5.1 | |||||
| 1″ | 17 | 15 | 13 | 14 | 13 | 11 | 12 | 11 | 9.4 | 8.4 | 7.7 | 6.7 | |||||
| 11/8″ | 21 | 19 | 17 | 18 | 16 | 14 | 15 | 13 | 12 | 10 | 9.5 | 8.4 | |||||
| 6 × 37 Classification | |||||||||||||||||
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| 11/4″ | 25 | 22 | 20 | 21 | 19 | 17 | 17 | 16 | 14 | 12 | 11 | 9.8 | |||||
| 13/8″ | 30 | 27 | 24 | 26 | 23 | 20 | 21 | 19 | 17 | 15 | 13 | 12 | |||||
| 11/2″ | 35 | 32 | 28 | 30 | 27 | 24 | 25 | 22 | 20 | 17 | 16 | 14 | |||||
| 13/4″ | 48 | 43 | 38 | 41 | 37 | 33 | 34 | 30 | 27 | 24 | 21 | 19 | |||||
| 2″ | 62 | 55 | 49 | 53 | 48 | 43 | 43 | 39 | 35 | 31 | 28 | 25 | |||||
| (A)—Socket or Swaged Terminal attachment. | |||||||||||||||||
| (B)—Mechanical Sleeve attachment. | |||||||||||||||||
| (C)—Hand Tucked Splice attachment. | |||||||||||||||||
| Improved plow steel, rope diameter, inches | Number of clips | Minimum spacing, inches | |
|---|---|---|---|
| Drop forged | Other material | ||
| (1) | |||
| 1/2 | 3 | 4 | 3 |
| 5/8 | 3 | 4 | 33/4 |
| 3/4 | 4 | 5 | 41/2 |
| 7/8 | 4 | 5 | 51/4 |
| 1 | 4 | 6 | 6 |
| 11/8 | 5 | 6 | 63/4 |
| 11/4 | 5 | 7 | 71/2 |
| 13/8 | 6 | 7 | 81/4 |
| 11/2 | 6 | 8 | 9 |
| 1 Three clips shall be used on wire size less than 1/2-inch diameter. | |||
| [In pounds or tons of 2,000 pounds] | ||||
| Nominal size chains stock | Single leg | 60° bridle | 45° bridle | 30° bridle |
|---|---|---|---|---|
| 1/4″ 1 | 1060 | 1835 | 1500 | 1060 |
| 5/16″ 1 | 1655 | 2865 | 2340 | 1655 |
| 3/8″ 1 | 2385 | 2.1 | 3370 | 2385 |