High-quality tow cables for Tata Steel's 024 wheel excavator
Wheel excavator 024 is a machine on the Tata Steel site in IJmuiden. The ore that arrives here by ship is transferred by cranes onto a large conveyor belt and stored in the ore field. The wheel excavator then digs up the ore again to transport it further on another conveyor belt, so that it eventually ends up in the blast furnaces. The long arm of the wheel excavator is connected to the counterweight with two guy cables.
Rejected due to corrosion
Mennens carried out the annual inspection on the guy cables supplied by Verto in 1991. Frits van Boetzelaer explains: ‘The cables were rejected according to the standard on the basis of corrosion. Tata Steel then asked us to make an offer.’
Strict quality and material requirements
This is a specialist job. Ben Haarsma: "Tata Steel has strict requirements for the quality of both the workmanship and the material. Tata IJmuiden has its own inspection service. It also involves a special type of steel cable (“locked coil”). The construction of this steel cable is unique. A standard steel cable has round wires, while the locked coil has profiled wires. The profiles interlock, resulting in an almost solid steel cable with a very high breaking force. This steel cable is therefore not very flexible."
The locked coil steel cable is solid and has minimal stretch.
End connection and length determination
A steel cable is fitted with a custom-made end connection, a socket, at both ends. Ben: ‘Because this cable is so rigid, we had to work very carefully. We insert the cable through the socket and then make a “plume”. We do this very carefully to prevent permanent damage to the steel cable. We then pull the cable with the plume into the socket and fill the socket with synthetic resin.’
Length determination
The length determination was also specialised, adds Frits. ‘Normal steel cables have a little stretch. The cables are measured under pre-tension and then cut to the exact length. With an almost solid cable, this requires even greater precision.’
Transport
Once the steel cables had been assembled by Mennens and approved by Tata Steel's inspection service, they were ready to be transported to IJmuiden. Frits: ‘The cables are 23 metres long and have a diameter of 92 mm. Due to their solid construction, they had to be transported in their full length on a frame via the A27, A2 and A9 motorways.’
Collaboration
Throughout the entire process, Mennens maintained close contact with Tata Steel and other companies involved, including Mammoet, which provided the scaffolding for assembling the cables on site. Frits: "A project like this requires constant good cooperation and clear communication with all parties involved. We are proud that we, as a team – both internally and externally – have completed this specialist job. A “strong piece of steel cable”!"
Tata Steel has now successfully installed the steel cables for wheel excavator 024. Later this year, Mennens will deliver another two locked coil cables for wheel excavator 023.
