07/08/2020 – Order from SIJ Metal Ravne, Slovenia

Andritz supply heat treatment plant

International technology group Andritz has received an order from SIJ Metal Ravne, Slovenia, for the supply of a complete heat treatment plant.


Example of furnaces with basins and charging machine. © Andritz


The plant includes two Andritz Maerz double-chamber furnaces, a charging machine and high-volume quenching tanks, as well as an automation system. The commissioning is scheduled for the second quarter of 2021.

With this investment, SIJ Metal Ravne will receive a special furnace for the most demanding heat treatment of products used in the energy sector, the aircraft industry and other special applications for which the company plans growth in the coming years in line with its business strategy.

Each Andritz Mearz double-chamber furnace consists of a high-temperature furnace (650°C to 1,220°C) with recuperative burners and a low-temperature furnace (200°C to 830°C) with forced circulation. Both furnace types meet the qualifications for AMS 2750 E classification 2, which requires very high precision in the thermal process (±6°C).

The charging machine is designed as a portal-type unit for handling charging material up to 25t. The high-volume quenching tanks using polymer and water also comprise the complete water treatment plant and four cooling towers located outside the production hall. Andritz engineers will optimise the cooling medium flow structures within the quenching tanks by using computational fluid dynamics (CFD), including conjugated heat transfer.

The SIJ Group is the biggest vertically integrated Slovenian steel producer and one of the largest producers of stainless and special steels in Europe. SIJ Metal Ravne from the SIJ Group is the third largest tool steel producer in the European Union. The company produces a broad range of more than 200 steel grades in different dimensional shapes, from carbon and alloyed structural steels to tool and special steels in the form of rolled and forged products.