Overview
19 X 7 CLASSIFICATION In an application where a single part hoist rope is used to lift a free load, or where rotation resistant properties are essential for rope performance, a 19 x 7 rope can be used. The rotation resistant characteristic of 19 x 7 rope is achieved by laying six strands around a core strand in one direction, and then laying 12 strands around the first operation in the opposite direction. Thus, when the rope is in tension, opposing rotational forces are created between the inner and outer layers. Ropes of 19 x 7 construction require special handling, selection and usage considerations, due to their construction. They are susceptible to kinking, crushing and unbalancing in the form of "core pops" and birdcages". Extreme care must be taken to avoid operational practices which can lead to these conditions. In addition, frequent, regular inspection for broken wires is critical when using 19 x 7. By design, the 19 x 7 construction has a relatively low reserve strength. This can result in short service life between the point in time when the broken wire report criteria are met and when actual rope fracture occurs.
