Section 24.39.80.353 - LINES, SHACKLES AND BLOCKS01.General Requirements.a. All lines, shackles, blocks, etc., should be maintained in good condition and shall be of sufficient size, diameter and material to withstand one and one half (1 1/2) times the maximum stress imposed.b. Wire rope or other rigging equipment which shows a fifteen percent (15%) reduction in strength shall be replaced.02.Splices. a. Two (2) lines may be connected by a long splice, or by shackles of patent links of the next size larger than the line where practical.b. A safe margin of line must be used for making long splices. See Table 353.02.b. TABLE 353.02.b. |
Rope Diameter | Unraveled | Total Length |
3/8" | 8' | 16' |
5/8" | 13' | 20' |
3/4" | 15' | 30' |
7/8" | 18' | 36' |
1" | 20' | 40' |
03.Wire Rope Clips or Clamps. a. Clips should be spaced at least six (6) rope diameters apart to achieve maximum holding power. See Table 353.03.a.
TABLE 353.03.a. |
Diameter of Rope | Number of Clips | Required Space Between Clips |
1-1/2-inch | 8 | 10 inches |
1-3/8-inch | 7 | 9 inches |
1-1/4-inch | 6 | 8 inches |
1-1/8-inch | 5 | 7 inches |
1- inch | 5 | 6 inches |
7/8-inch | 5 | 5-1/4 inches |
3/4-inch | 5 | 5-1/2 inches |
3/8 to 5/8-inch | 4 | 3 inches |
b. Clips should always be attached with the base or saddle of the clip against the longer or "live" end of the rope. See Figure 353.03.b. This is the only approved method. FIGURE 353.03.b.
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d. After the rope has been used and is under tension, the clips should again be tightened to take up any looseness caused by the tension reducing the rope diameter. Remember that even when properly applied a clip fastening has only about ninety percent (90%) of the strength of the rope and far less than that when rigged improperly.e. U-bolt wire rope clamps must not be used to form eyes on running lines, skylines, machine guylines, or straps.04.Blocks. All blocks must be of steel construction or of material of equal or greater strength and so hung that they will not strike or interfere with other blocks or rigging.05.Pins. All pins in blocks shall be properly secured by keys of the largest size the pin hole will accommodate06.Shackles.a. Spread in jaws of shackles shall not exceed by more than one (1) inch the size of yoke or swivel of the block to which it is connected.b. All shackles must be made of forged steel or material of equivalent strength and one (1) size larger than the line it connects.07.Cable Cutting. Cable cutters, soft hammers, or a cutting torch shall be available and used for cutting cables. Eye protection must be used when cutting cable.08.Damaged or Worn Wire Rope. Worn or damaged wire rope creating a safety hazard shall be taken out of service or properly repaired before further use.Idaho Admin. Code r. 24.39.80.353