Rosendahl presents a newfield of technology. The Austrian cable machine maker has extended the know-how for steel rope extrusion, which is quite different to cable extrusion.

July 5, 2017

Extrusion technology is not only the line’s core, but Rosendahl’s business core, as well. This is where the company does most of their R&D activities and where they always get the best results for their customers. And now it is not only cables that Rosendahl extrudes. The Austrian cable machine maker has extended the know-how for steel rope extrusion, which, when it comes to the details, is quite different to cable extrusion.

Where are steel ropes applied?

Such jacketed steel ropes are commonly applied for stay cables or mono-strands. Stay cables are primarily used for cable-stayed bridges. Unbounded mono-strands are used in civil engineering in pre-stressed concrete structures (PT systems). Often, several single cables (mono-strand) are combined into a bundle (multi-strand), as well. A single strand usually has a diameter of 1/4” to 1 1/8”. Of course, other dimensions are also available.

The requirements of extruding steel ropes

Before jacketing, these strands are coated with a special anti-corrosion material. Rosendahl applies a permanent elastic corrosion protection, grease or wax, to those strands. This coating provides corrosion protection and length water tightness, and it reduces internal friction.

The tricky part is to coat the individual steel wires with grease or wax. Specifically, for this type of rope preservation, Rosendahl has developed the new rope conservation machine which is used immediately prior to the application of the PE jacket. They have introduced a new online monitoring system for the grease/wax coating application. This ensures high quality and performance control during the entire conservation process.