The Meaning of Lay in Wire Rope Design
In wire rope design, the term lay has three separate meanings. The first two meanings describe the wire and position of stranding within the rope. The other, third, meaning is a measurement of length used mainly for manufacturing and inspection. Below, we want to go over the three different meanings in more depth.
The direction of strands in the lay and the direction of wire lay in strands determine characteristics of the wire rope. Wires that maintain a regular lay appear to run straight down the length of the rope, whereas a lang lay appears to angle across the wire rope. Regular lay ropes have wires laid in the strand opposite the direction to strand lays in the rope. Lang lay wires are focused in the same direction as the strand in the rope.
The direction that strands lay in is either right or left. As you look down a rope, you should notice strands of a right lay rope move away from you to the right, whereas the left lay in the opposite direction.
The length that goes along the rope, and takes one complete spiral around the core, is a frequently used measurement during wire rope inspections. Regulations and standards require the removal of a certain number of broken wires per each rope lay.