North American steelmaker Steel Dynamics, one of the largest domestic producers and metals recyclers in the USA, has contracted Fives, an international engineering group, to upgrade its continuous galvanising line number two (CGL №2) at the Flat Roll Group (Columbus Division) located in Mississippi.
The aim of the project is to increase the production capacity of CGL №2 by increasing the maximum strip speed. The basis for the capacity increase was developed using Fives’ speciality software, DMS OptiLine, which simulates the complete operation of a strip processing line. DMS OptiLine calculates the requested characteristics of each of the line's motors in order to guarantee the required line tension during operation at the targeted increased speed, as well as during line acceleration and deceleration.
The line speed increase requires mechanical and cleaning equipment upgrades in order to achieve quality product output. A new entry section configuration was employed including new bridle rolls, deflector rolls and a burr masher. The cleaning section is to be upgraded with a high pressure hot water system, additional spray degreasing capacity and a new rinsing brush machine.
Fives will supply a new DMS rotary shear at the exit section of the line to achieve fast cutting of the strip for an improved exit time cycle. The DMS rotary shear is a plug-and-play system that cuts the strip while it is moving, and is synchronized with the line speed, thus guaranteeing higher production with optimum strip end quality.
The plan is to design and supply the equipment within 12 months in order to launch a revamped line by November 2019.
Fives will also be revamping steelmaking equipment for Lusosider Aços Planos of Portugal. The plan is to revamp the bridle rolls on the skin-pass section of a continuous galvanising line (CGL) which has already been upgraded by the group.
The revamping project will increase operational reliability and facilitate maintenance. Fives will replace the existing combination of the entry gearbox and exit bridle rolls of the skin-pass with newly designed bridle rolls and will provide individual motorisation for each motorised roll. A new DMS burr masher will also be installed as part of the project, and an existing zinc bath gauge will be relocated to fit the new configuration.
Lusosider is part of the world integrated industrial complex CSN and has been a long-term partner of Fives. In 2000, it contracted the group to revamp an existing CGL to increase line capacity in order to produce low carbon steel for construction. In 2016, to increase capacity further, Fives revamped the horizontal furnace of the line and installed an additional jet cooling unit.
The new equipment will be designed, delivered and commissioned by July 2019.