Steel wire rope rejection standards for bridge girder launcher
As main lifting tools for the bridge girder launcher, the steel wire rope plays a crucial role in the bridge construction. Its intactness and good performance affect normal construction and personal safety, so keep an eye on check of the steel wire rope as it is lifting and lowering heavy objects. And follow contents in below tables to find more:
Table 1 Steel wire rope rejection standards (within one lay)
Safety coefficient of steel wire rope |
Rejection standards for steel wire rope | |||
6 x 19 = 114 | 6 x 37 = 222 | |||
Regular lay | Lang lay | Regular lay | Lang lay | |
12 | 6 | 22 | 11 |
Note: The regular lay of 6 x 37 is widely selected for the electric hoist. The steel wire rope should be rejected when the broken wire within one lay reaches 22. When even wear or corrosion is found on the external layer of the wire at any section of the steel wire rope, the rejection standards shall be decreased as stated in Table 2
Table 2 Convert the wire diameter abrasion into broken pieces
Wear or corrosion proportion of exterior steel wire rope (%) | Equivalent proportion of broken wires within one lay in table (%) |
10 | 84 |
15 | 76 |
20 | 68 |
25 | 60 |
30-40 | 50 |