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Nothing in the way of this mill scale

At a continuous casting plant steel ingots are cast and then cut to appropriate length. Due to the high temperatures, scale develops on the outside of the ingots and is rinsed away in chutes with water to a basin. The scale takes the form of grains some 5 mm in size and causes serious wear in the chutes. Nowadays it has become a standard throughout the world to line such chutes with ABRESIST fused basalt. The smooth surface reduces any deposition of material during transport, as well as protecting against abrasion wear.

The company in question had previously used stainless steel sheets in its chutes. However, it turned out that the surface of such sheeting was neither smooth enough nor hard enough to withstand the problems of abrasion and frictional wear posed by the mill scale. The sheets became scoured and as a result turbulence arose in the chutes. This in turn led to deposition and blockages due to scale accumulating in the chutes. There needed to be a complete shutdown of production for sixteen hours every three weeks in order for the chutes to be cleaned and made fit for use once more. Since the entire plant was affected by this, the production downtime resulted in heavy costs.

Kalenborn got the contract to line the channels with ABRESIST thanks to their many years of cooperation, experience and technical advice during the tendering and project planning phases. A wear protection solution was worked out in conjunction with the client and a fine installation team was organised to try and reduce these downtimes for the entire facility as much as possible.

Lining of the chutes with ABRESIST took place in several phases of construction, but with a high level of coordination and planning work to ensure almost unbroken operation of the plant during the job. During these repairs, the basic concrete structure was reconstructed from the ground up. After that, the installation team lined four different sections along with the confluences and the main chute leading to the settling basin. The installation of ABRESIST fused cast basalt also involved the use of quick-hardening KALFIX mortar to enable the plant and its fittings to be recommissioned as quickly as possible.

The project was completed to the total satisfaction of the client. The timing was perfect, in spite of the difficult working conditions in tight spaces, the high temperatures prevailing and the time pressure during the implementation of the project.

An assessment was then made after eight months of operation with the new installation. The state of the ABRESIST lining inside the roll scale chutes was still perfect. The flow of water and scale through the chutes had improved and it had been possible to make a massive reduction in the amount of cleaning work. Equally the downtimes for maintenance of the scale run-off chutes had been significantly reduced.