The Invisible Carriers of Safety: Steel Ropes
When it comes to elevator safety, steel ropes are undoubtedly among the first components that come to mind. Connecting the car to the counterweight and turning the motor's torque into motion, they are under constant tension, bending and friction. Yet the answer to "When should the ropes be replaced?" is not just a matter of time. The decision is based on a combination of many parameters, such as technical inspections, the limits set by standards and how heavily the elevator is used. In this guide, prepared with Liftland's expertise, we look at all the signs that an elevator rope is due for retirement.
1. Broken Wires: The Visible Danger
Steel ropes consist of hundreds of fine wires laid in a specific pattern. Over time, metal fatigue and movement over the sheave cause these wires to start breaking. Under the EN 12385 standards, the number of broken wires within a given lay length (a length equal to a set multiple of the rope diameter) is the main criterion for replacement. If breaks are concentrated in a single strand, or if broken outer wires reach a critical percentage of the total, the elevator must be taken out of service and the ropes replaced.
2. Diameter Reduction and Wear
As ropes are used, contact between the outer wires and the sheave causes wear and the nominal diameter of the rope decreases. According to the standards, if a rope's diameter has shrunk by more than 6% of its nominal value (up to 10% in some special cases), its load-bearing capacity and elasticity have fallen to a risky level.
How to Measure: Always use a calliper and take the two widest points of the rope as reference. Diameter reduction can also be linked to the collapse of the rope's core (fibre or steel), which is a sign of internal corrosion.
"Rope replacement is not a cost; it is the most critical investment for the safety of lives and the sustainability of the system."
3. Corrosion and Rust
A damp shaft or insufficient lubrication causes the ropes to oxidise (rust). Corrosion weakens the bond between the wires and destroys the rope's flexibility. If a layer of "red powder", a sign of internal wear, has formed on the rope surface, the rope is deteriorating from the inside. Even without visible broken wires, this carries a risk of sudden failure, so replacement is essential.
4. Sheave and Rope Compatibility
The condition of the traction sheave must also be examined when deciding to replace ropes. A sheave with worn grooves will deform new ropes very quickly. "V" grooves turning into "U" grooves, or differences in depth between grooves, make the ropes run at different speeds and wear out early. In most cases, regrinding or replacing the sheave is recommended together with the rope replacement.
5. "Birdcaging" and Mechanical Deformation
When a rope suddenly slackens at one point and the strands spring outwards, this is called "birdcage" deformation. It usually results from sudden braking, the rope jumping off the sheave or incorrect installation. A rope with this kind of permanent deformation has lost its load-bearing balance and must be replaced immediately.
5 Critical Signs That Ropes Need Replacing:
Conclusion: The Importance of Periodic Inspection
Depending on the age of the building and how often the elevator is used, ropes last an average of 5 to 10 years. In high-traffic buildings, this can drop to 2-3 years. Monthly maintenance and annual inspections (the periodic inspection labelling process in Türkiye) are a legal requirement for monitoring the condition of the ropes.
At Liftland, we provide professional service for the supply, installation and technical inspection of steel ropes, the most critical part of your elevator. Don't leave your safety to chance; if you have doubts about the condition of your ropes, request a free site survey from our expert team.